Fractures of the lower extremity in the practice of general practitioners and family medicine.

Fractures of the lower extremity in the practice of general practitioners and family medicine. Features of diagnosis and first aid in outpatient family doctor. Formation route patient with trauma musculoskeletal system. Drug-employment medical and social assessment. Principles of rehabilitation.

 

Femoral Head

EPIDEMIOLOGY

• Almost all are associated with hip dislocations.

• These fractures complicate 10% of posterior hip dislocations.

• Most are shear or cleavage type, although recently, more indentation-type or crush-type fractures have been recognized with the increased use of computed tomography (CT).

• Indentation fractures are more commonly associated with anterior hip dislocations (25% to 75%).

ANATOMY

• The femoral head receives its blood supply from three sources (Fig. 1):

• The medial femoral circumflex artery supplies the majority of the superior weight-bearing portion.

• The lateral femoral circumflex artery and the artery of the ligamentum teres supply the remainder.

• Seventy percent of the femoral head articular surface is involved in load transfer, and thus damage to this surface may lead to the development of posttraumatic arthritis.

MECHANISM OF INJURY

• Most femoral head fractures are secondary to motor vehicle accidents, with axial load transmission proximally through the femur.

• If the thigh is neutral or adducted, a posterior hip dislocation with or without a femoral head fracture may result. These fractures may be the result of avulsion by the ligamentum teres or cleavage by the posterior acetabular edge.

• In anterior dislocations, impacted femoral head fractures may occur because of a direct blow from the acetabular margin.

CLINICAL EVALUATION

• Formal trauma evaluation is necessary because most femoral head fractures are a result of high-energy trauma.

• Ninety-five percent of patients have injuries that require inpatient management independent of femoral head fracture.

• In addition to hip dislocation, femoral head fractures are also associated with acetabular fractures, knee ligament injuries, patella fractures, and femoral shaft fractures.

• A careful neurovascular examination is essential, because posterior hip dislocations may result in neurovascular compromise.

RADIOGRAPHIC EVALUATION

• Anteroposterior (AP) and Judet (45-degree oblique) views of the pelvis should be obtained.

• Hip dislocation is almost always present.

Figure 1. Vascular anatomy of the femoral head and neck. Top: Anterior aspect. Bottom: Posterior aspect. LFC, lateral femoral circumflex artery. (From Rockwood CA Jr, Green DP, Bucholz RW, Heckman JD, eds. Rockwood and Green’s Fractures in Adults, 4th ed, vol. 2. Philadelphia: Lippincott-Raven, 1996:1662.)

• The AP radiograph of the pelvis may demonstrate femoral head fragments in the acetabular fossa.

• If closed reduction is successful, CT is necessary to evaluate the reduction of the femoral head fracture and to rule out the presence of intraarticular fragments that may prevent hip joint congruity.

• Some authors recommend CT evaluation even if the closed reduction is unsuccessful to evaluate associated acetabular fractures.

• 
  
  Sagittal CT

  reconstruction may also be helpful in delineating the femoral head fracture.

CLASSIFICATION

Pipkin (Fig. 2)

Type I:	Hip dislocation with fracture of the femoral head inferior to the fovea capitis femoris
Type II:	Hip dislocation with fracture of the femoral head superior to the fovea capitis femoris
Type III:	Type I or II injury associated with fracture of the femoral neck
Type IV:	Type I or II injury associated with fracture of the acetabular rim

 

Brumback et al.

Type 1A:	Posterior hip dislocation with femoral head fracture involving the inferomedial (non-weight-bearing) portion of the head and minimal or no fracture of the acetabular rim with stable hip joint after reduction
1B:	Type 1A with significant acetabular fracture and hip instability
Type 2A:	Posterior hip dislocation with femoral head fracture involving the superomedial (weight-bearing) portion of the head and minimal or no fracture of the acetabular rim with stable hip joint after reduction
2B:	Type 2A with significant acetabular fracture and hip instability
Type 3A:	Any hip dislocation with femoral neck fracture
3B:	Any hip dislocation with femoral neck and head fracture
Type 4A:	Anterior dislocation of the hip with indentation of the superolateral weight-bearing surface of the femoral head
4B:	Anterior dislocation of the hip with transchondral shear fracture of the weight-bearing surface of the femoral head
Type 5:	Central fracture-dislocations of the hip with fracture of the femoral head

 

Figure 2. The Pipkin classification of dislocations with femoral head fractures. (A) Type I. (B) Type II. (C) Type III. (D) Type IV. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

 

OTA Classification of Femoral Head Fractures

See Fracture and Dislocation Compendium at http://www.ota.org/compendium/index.htm.

TREATMENT

Pipkin Type I

The femoral head fracture is inferior to the fovea. These fractures occur in the non-weight-bearing surface.

• If reduction is adequate (<1 mm step-off) and the hip is stable, closed treatment is recommended.

• If the reduction is not adequate, open reduction and internal fixation with small subarticular screws using an anterior approach are recommended.

• Small fragments may be excised if they do not sacrifice stability.

Pipkin Type II

The femoral head fracture is superior to the fovea. These fractures involve the weight-bearing surface.

• The same recommendations apply for the nonoperative treatment of Type II fractures as for Type I fractures, except that only an anatomic reduction as seen on CT and repeat radiographs can be accepted for nonoperative care.

• Open reduction and internal fixation generally comprise the treatment of choice through an anterior approach.

Pipkin Type III

A femoral head fracture occurs with an associated fracture of the femoral neck.

• The prognosis for this fracture is poor and depends on the degree of displacement of the femoral neck fracture.

• In younger individuals, emergency open reduction and internal fixation of the femoral neck are performed, followed by internal fixation of the femoral head. This can be done using an anterolateral (Watson-Jones) approach.

• In older individuals with a displaced femoral neck fracture, prosthetic replacement is indicated.

Pipkin Type IV

A femoral head fracture occurs with an associated fracture of the acetabulum.

• This fracture must be treated in tandem with the associated acetabular fracture.

• The acetabular fracture should dictate the surgical approach, and the femoral head fracture, even if nondisplaced, should be internally fixed to allow early motion of the hip joint.

Femoral Head Fractures Associated with Anterior Dislocations

• These fractures are difficult to manage.

• Indentation fractures, typically located on the superior aspect of the femoral head, require no specific treatment, but the fracture size and location have prognostic implications.

• Displaced transchondral fractures that result in a nonconcentric reduction require open reduction and either excision or internal fixation, depending on fragment size and location.

COMPLICATIONS

• Osteonecrosis:
• Patients with posterior hip dislocations with an associated femoral head fracture are at high risk for developing osteonecrosis and posttraumatic degenerative arthritis. The prognosis for these injuries varies. Pipkin Types I and II are reported to have the same prognosis as a simple dislocation (1% to 10% if dislocated <6 hours). Pipkin Type IV injuries seem to have roughly the same prognosis as acetabular fractures without a femoral head fracture. Pipkin Type III injuries have a poor prognosis, with a 50% rate of posttraumatic osteonecrosis.

• Ten percent of patients with anterior dislocations develop osteonecrosis. Risk factors include a time delay in reduction and repeated reduction attempts.

• Posttraumatic osteoarthritis: Risk factors include transchondral fracture, indentation fracture greater than 4 mm in depth, and osteonecrosis.

 

Femoral Neck Fractures

EPIDEMIOLOGY

• More than 250,000 hip fractures occur in the United States each year (50% involve the femoral neck), and this number is projected to double by the year 2040.

• The average age of occurrence is 77 years for women and 72 years for men.

• 80% occur in women, and the incidence doubles every 5 to 6 years in women age >30 years.

• The incidence in younger patients is very low and is associated mainly with high-energy trauma.

• Risk factors include female sex, white race, increasing age, poor health, tobacco and alcohol use, previous fracture, fall history, and low estrogen level.

ANATOMY

• The upper femoral epiphysis closes by age 16 years.

• Neck-shaft angle: 130В±7 degrees
• Femoral anteversion: 10В±7 degrees
• There is minimal periosteum about the femoral neck; thus, any callus that forms must do so by endosteal proliferation.

• Calcar femorale: This is a vertically oriented plate from the posteromedial portion of the femoral shaft radiating superiorly toward the greater trochanter (Fig. 3).

•  

Figure 3. Left: The calcar femorale is a vertical plate of bone that originates in the posteromedial portion of the femoral shaft under the lesser trochanter and radiates laterally toward the posterior aspect of the greater trochanter. Right: The calcar femorale fuses with the posterior aspect of the femoral neck superiorly and extends distally anterior to the lesser trochanter and fuses with the posteromedial aspect of the femoral diaphysis. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

• The capsule is attached anteriorly to the intertrochanteric line and posteriorly 1 to 1.5 cm proximal to the intertrochanteric line.

• Three ligaments attach in this region:

• Iliofemoral: Y-ligament of Bigelow (anterior)

• Pubofemoral: anterior
• Ischiofemoral: posterior
• Vascular supply (Fig. 4):
• Base of the femoral neck: An extracapsular ring is formed anteriorly by the ascending branch of the lateral femoral circumflex artery and posteriorly by the medial femoral circumflex artery.

• The ascending cervical branches from this ring pierce the hip capsule near its distal insertion, becoming the retinacular arteries coursing along the femoral neck. Most supplying the femoral head are posterosuperior in location.
• A subsynovial intracapsular arterial ring is formed by these retinacular arteries at the base of the femoral head. As they enter the femoral head, they unite to form the lateral epiphyseal arteries.

• The lateral epiphyseal arteries that arise from the posterosuperior ascending cervical branches supply the majority of the femoral head.

• The artery of the ligamentum teres, usually a branch of the obturator, offers a small supplemental contribution to the femoral head and is limited to the area around the fovea capitis.

Figure 4. Vascular anatomy of the femoral head and neck. Top: Anterior aspect. Bottom: Posterior aspect. LFC, lateral femoral circumflex artery. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

•  Forces acting across the hip joint:

• Straight leg raise: 1.5 Г— body weight

• One-legged stance: 2.5 Г— body weight

• Two-legged stance: 0.5 Г— body weight

• Running: 5.0 Г— body weight
• Internal anatomy: The direction of the trabeculae parallels the direction of compressive forces. The bony trabeculae are laid down along the lines of internal stress. A set of vertically oriented trabeculae results from the weight-bearing forces across the femoral head, and a set of horizontally oriented trabeculae results from the force of the abductor muscles. These two trabeculae systems cross each other at right angles (Fig. 5).

Cyclical loading-stress fractures: These are seen in athletes, military recruits, ballet dancers; patients with osteoporosis and osteopenia are at particular risk.

Figure 5. Anatomy of the bony trabeculae in the proximal end of the femur. In a nonosteoporotic femur, all five groups of bony trabeculae are readily evident on x-ray. The Ward triangle (W) is a small area in the neck of the femur that contains thing and loosely arranged trabeculae only. (From Rockwood CA Jr, Green DP, Bucholz RW, Heckman JD, eds. Rockwood and Green’s Fractures in Adults, 4th ed, vol. 2. Philadelphia: Lippincott-Raven, 1996:1667.)

MECHANISM OF INJURY

• Low-energy trauma; most common in older patients:

• Direct: A fall onto the greater trochanter (valgus impaction) or forced external rotation of the lower extremity impinges an osteoporotic neck onto the posterior lip of the acetabulum (resulting in posterior comminution).

• Indirect: Muscle forces overwhelm the strength of the femoral neck.

• High-energy trauma: This accounts for femoral neck fractures in both younger and older patients, such as motor-vehicle accident or fall from a significant height.

 

CLINICAL EVALUATION

• Patients with displaced femoral neck fractures typically are nonambulatory on presentation, with shortening and external rotation of the lower extremity. Patients with impacted or stress fractures may however demonstrate subtle findings, such as anterior capsular tenderness, pain with axial compression, lack of deformity, and they may be able to bear weight.

• Pain is evident on range of hip motion, with possible pain on axial compression and tenderness to palpation of the groin.

• An accurate history is important in the low-energy fracture that usually occurs in older individuals. Obtaining a history of loss of consciousness, prior syncopal episodes, medical history, chest pain, prior hip pain (pathologic fracture), and preinjury ambulatory status is essential and critical in determining optimal treatment and disposition.

• One should assess the wrist and shoulders in elderly individuals because 10% have associated upper extremity injuries.

RADIOGRAPHIC EVALUATION

• An anteroposterior (AP) view of the pelvis and an AP and a cross-table lateral view of the involved proximal femur are indicated (Fig. 6).

• An internal rotation view of the injured hip may be helpful to further clarify the fracture pattern.

• Technetium bone scan or preferably magnetic resonance imaging may be of clinical utility in delineating nondisplaced or occult fractures that are not apparent on plain radiographs.

Figure 6. A cross-table lateral view of the affected hip is obtained by flexing the uninjured hip and knee 90 degrees and aiming the beam into the groin, parallel to the floor and perpendicular to the femoral neck (not the shaft). This allows orthogonal assessment of the femoral neck without the painful and possible injurious manipulation of the effected hip required for a frog-leg lateral view. (From Bucholz RW, Heckman JD, eds. Rockwood and Green’s Fractures in Adults, 5th ed. Baltimore: Lippincott Williams & Wilkins, 2002.)

 

CLASSIFICATION

Anatomic Location

• Subcapital
• Transcervical
• Basicervical

Pauwel

This is based on the angle of fracture from the horizontal (Fig. 7).

Type I:	30 degrees
Type II:	50 degrees
Type III:	70 degrees

Increasing shear forces with increasing angle lead to more fracture instability.

 

Figure 7. The Pauwel classification of femoral neck fractures is based on the angle the fracture forms with the horizontal plane. As a fracture progresses from Type I to Type III, the obliquity of the fracture line increases, and, theoretically, the shear forces at the fracture site also increase. (From Rockwood CA Jr, Green DP, Bucholz RW, Heckman JD, eds. Rockwood and Green’s Fractures in Adults, 4th ed, vol. 2. Philadelphia: Lippincott-Raven, 1996:1670.)

 

Garden

This is based on the degree of valgus displacement (Fig. 8).

Type I:	Incomplete/valgus impacted
Type II:	Complete and nondisplaced on AP and lateral views
Type III:	Complete with partial displacement; trabecular pattern of the femoral head does not line up with that of the acetabulum
Type IV:	Completely displaced; trabecular pattern of the head assumes a parallel orientation with that of the acetabulum

 

Figure 8. The Garden classification of femoral neck fractures. Type I fractures can be incomplete, but much more typically they are impacted into valgus and retroversion (A). Type II fractures are complete, but undisplaced. These rare fractures have a break in the trabeculations, but no shift in alignment (B). Type III fractures have marked angulation, but usually minimal to no proximal translation of the shaft (C). In the Garden Type IV fracture, there is complete displacement between fragments, and the shaft translates proximally (D). The head is free to realign itself within the acetabulum, and the primary compressive trabeculae of the head and acetabulum realign (white lines). (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Baltimore: Lippincott Williams & Wilkins, 2005.)

 

OTA Classification of Femoral Neck Fractures

See Fracture and Dislocation Compendium at http://www.ota.org/compendium/index.htm.

Because of too poor intraobserver and interobserver reliability in using the various classifications, femoral neck fractures are commonly described as either:

• Nondisplaced: impacted valgus femoral neck fractures/stress fractures: This is a much better prognostic situation.

• Displaced: Characterized by any detectable fracture displacement.

TREATMENT

• Goals of treatment are to minimize patient discomfort, restore hip function, and allow rapid mobilization by obtaining early anatomic reduction and stable internal fixation or prosthetic replacement.

• Nonoperative treatment for traumatic fractures is indicated only for patients who are at extreme medical risk for surgery; it may also be considered for demented nonambulators who have minimal hip pain.

Early bed to chair mobilization is essential to avoid increased risks and complications of prolonged recumbency, including poor pulmonary toilet, atelectasis, venous stasis, and pressure ulceration.

 

Fatigue/Stress Fractures

• Tension-sided stress fractures (seen at the superior lateral neck on an internally rotated AP view): These are at significant risk for displacement; in situ screw fixation is recommended.

• Compression-sided stress fractures (seen as a haze of callus at the inferior neck): These are at minimal risk for displacement without additional trauma; protective crutch ambulation is recommended until asymptomatic.

Impacted/Nondisplaced Fractures

• Approximately 8% to 33% of “impacted” fractures will displace without internal stabilization, decreasing to <5% with internal fixation.

• Less than 10% develop osteonecrosis secondary to kinking of the lateral epiphyseal vessels and tethering of the medial vessels in a valgus position or intracapsular hypertension.

• In situ fixation with three cancellous screws is indicated; exceptions are pathologic fractures, severe osteoarthritis/rheumatoid arthritis, Paget disease, and other metabolic conditions, which require prosthetic replacement.

Displaced Fractures

• Young patient with high-energy injury and normal bone: Urgent closed/open reduction with internal fixation and capsulotomy is performed.

• Elderly patients: Treatment is controversial:

• High functional demands and good bone density: Use closed/open reduction and internal fixation versus total hip replacement.

• Normal to intermediate longevity but poor bone density, chronic illness, and lower functional demands: Perform modular unipolar or bipolar hemiarthroplasty.

• Low demand and poor bone quality: Perform hemiarthroplasty using a one-piece unipolar prosthesis.

• Severely ill, demented, bedridden patients: Consider nonoperative treatment or prosthetic replacement for intolerable pain.

Operative Treatment Principles

• Fracture reduction should be achieved in a timely fashion. Risk of osteonecrosis may increase with increasing time to fracture reduction. Furthermore, the quality of fracture reduction is believed to be the most predictive factor under the surgeon’s control for loss of fixation.

• Fracture reduction maneuver: Perform hip flexion with gentle traction and external rotation to disengage the fragments, then slow extension and internal rotation to achieve reduction. Reduction must be confirmed on the AP and lateral images.

• Guidelines for acceptable reduction: On the AP view, valgus or anatomic alignment is seen; on the lateral view, maintain anteversion while avoiding any posterior translation of the fracture surfaces.

• Posterior comminution must be assessed.

• Internal fixation
• Multiple screw fixation: This is the most accepted method of fixation. Threads should cross the fracture site to allow for compression.

• Three parallel screws are the usual number for fixation. Additional screws add no additional stability and increase the chances of penetrating the joint. The screws should be in an inverted triangular configuration with one screw adjacent to the inferior femoral neck and one adjacent to the posterior femoral neck.

• Avoid screw insertion distal to the lesser trochanter secondary to a stress riser effect and risk of subsequent subtrochanteric fracture.

• Sliding-screw sideplate devices: If they are used, a second pin or screw should be inserted superiorly to control rotation during screw insertion.

• Prosthetic replacement
• Hemiarthroplasty:
• Advantages over open reduction and internal fixation:

• It may allow faster full weight bearing.

• It eliminates nonunion, osteonecrosis, failure of fixation risks (>20% to 30% of cases with open reduction and internal fixation require secondary surgery).

• Disadvantages:
• It is a more extensive procedure with greater blood loss.

• A risk of acetabular erosion exists in active individuals.

• Indications for hemiarthroplasty:
• Comminuted, displaced femoral neck fracture in the elderly

• Pathologic fracture
• Poor medical condition
• Poorer ambulatory status before fracture
• Neurologic condition (dementia, ataxia, hemiplegia, parkinsonism)

• Contraindications:
• Active sepsis
• Active young person
• Preexisting acetabular disease (e.g., rheumatoid arthritis)

• Bipolar versus Unipolar implants:
• Bipolar theoretically reduces the risk of acetabular erosion.

• Bipolar has a lower risk of postoperative dislocation.

• It is very hard to close reduce a dislocated bipolar prosthesis.

• Bipolar introduces the risk of polyethylene debris.

• Over time, the bipolar may lose motion at its inner bearing and functionally become unipolar.

• Unipolar is a less expensive implant.

• Cement versus noncemented:
• Better functional results with use of cement

• Risk of intraoperative hypotension and death with use of cement

• Primary total hip replacement:
• Recent enthusiasm has been reported with the use of total hip replacement for acute treatment of displaced femoral neck fractures.

• Studies have reported better functional results compared with hemiarthroplasty.

• It eliminates the potential for acetabular erosion.

• Disadvantages over hemiarthroplasty include a more extensive surgical procedure, increased implant cost, and a higher risk of prosthetic dislocation.

• Indications include:
• Preexisting ipsilateral degenerative disease.
• Active elderly individual with a displaced femoral neck fracture.

• Preexisting ipsilateral acetabular metastatic disease.

COMPLICATIONS

• Nonunion: This is usually apparent by 12 months as groin or buttock pain, pain on hip extension, or pain with weight bearing. It may complicate up to 5% of nondisplaced fractures and up to 25% of displaced fractures. Elderly individuals presenting with nonunion may be adequately treated with arthroplasty, whereas younger patients may benefit from cancellous bone grafting, proximal femoral osteotomy, or muscle pedicle graft.

• Osteonecrosis: This may present as groin, buttock or proximal thigh pain; it complicates up to 10% of nondisplaced fractures and up to 27% of displaced fractures. Not all cases develop evidence of radiographic collapse. Treatment is guided by symptoms.

• Early without x-ray changes: Protected weight bearing or possible core decompression.

• Late with x-ray changes: Elderly individuals may be treated with arthroplasty, whereas younger patients may be treated with osteotomy, arthrodesis, or arthroplasty.

• Fixation failure: This is usually related to osteoporotic bone or technical problems (malreduction, poor implant insertion). It may be treated with attempted repeat open reduction and internal fixation or prosthetic replacement.

• Prominent hardware may occur secondary to fracture collapse and screw backout.

 

Intertrochanteric Fractures

EPIDEMIOLOGY

• Intertrochanteric fractures account for nearly 50% of all fractures of the proximal femur.

• Average patient age of incidence is 66 to 76 years.

• The ratio of women to men ranges from 2:1 to 8:1, likely because of postmenopausal metabolic changes in bone.

• In the United States, the annual rate of intertrochanteric fractures in elderly women is about 63 per 100,000; in men, it is 34 per 100,000.

• Some of the factors associated with intertrochanteric rather than femoral neck fractures include advancing age, increased number of comorbidities, increased dependency in activities of daily living, and a history of other osteoporosis-related (“fragility”) fractures.

ANATOMY

• Intertrochanteric fractures occur in the region between the greater and lesser trochanters of the proximal femur, occasionally extending into the subtrochanteric region.

• These extracapsular fractures occur in cancellous bone with an abundant blood supply. As a result, nonunion and osteonecrosis are not major problems, as in femoral neck fractures.

• Deforming muscle forces will usually produce shortening, external rotation, and varus position at the fracture.

• Abductors tend to displace the greater trochanter laterally and proximally.

• The iliopsoas displaces the lesser trochanter medially and proximally.

• The hip flexors, extensors, and adductors pull the distal fragment proximally.

• Fracture stability is determined by the presence of posteromedial bony contact, which acts as a buttress against fracture collapse.

MECHANISM OF INJURY

• Intertrochanteric fractures in younger individuals are usually the result of a high-energy injury such as a motor vehicle accident or fall from a height.

• Ninety percent of intertochanteric fractures in the elderly result from a simple fall.

• Most fractures result from a direct impact to the greater trochanteric area.

CLINICAL EVALUATION

• Patients with nondisplaced fractures may be ambulatory and experience minimal pain.

• Patients with displaced fractures are nonambulatory, with the injured lower extremity shortened and externally rotated.

• Range of hip motion is typically painful.

• Common associated injuries include fractures of the distal radius, proximal humerus, ribs, and spine (compression fractures).

• Patients may have experienced a delay before hospital presentation, time usually spent on the floor and without oral intake. The examiner must therefore be cognizant of potential dehydration, nutritional, and pressure ulceration issues as well as hemodynamic instability, because intertrochanteric fractures may be associated with as much as a full unit of hemorrhage into the thigh.

RADIOGRAPHIC EVALUATION

• An anteroposterior (AP) view of the pelvis and an AP and a cross-table lateral view of the involved proximal femur are obtained.

• An internal rotation view of the injured hip may be helpful to clarify the fracture pattern further.

• Technetium bone scan or preferably magnetic resonance imaging may be of clinical utility in delineating nondisplaced or occult fractures that are not apparent on plain radiographs.

CLASSIFICATION

Evans (Fig. 9)

• This is based on prereduction and postreduction stability, that is, the convertibility of an unstable fracture configuration to a stable reduction.

• In stable fracture patterns, the posteromedial cortex remains intact or has minimal comminution, making it possible to obtain and maintain a stable reduction.

• Unstable fracture patterns are characterized by greater comminution of the posteromedial cortex. Although they are inherently unstable, these fractures can be converted to a stable reduction if medial cortical opposition is obtained.

• The reverse obliquity pattern is inherently unstable because of the tendency for medial displacement of the femoral shaft.

• The adoption of this system was important not only because it emphasized the important distinction between stable and unstable fracture patterns, but also because it helped define the characteristics of a stable reduction.

OTA Classification of Intertrochanteric Fractures

See Fracture and Dislocation Compendium at http://www.ota.org/compendium/index.htm.

• Several studies have documented poor reproducibility of results based on the various intertrochanteric fracture classification systems.

• Many investigators simply classify intertrochanteric fractures as either stable or unstable, depending on the status of the posteromedial cortex. Unstable fracture patterns comprise those with comminution of the posteromedial cortex, subtrochanteric extension, or a reverse obliquity pattern.

UNUSUAL FRACTURE PATTERNS

Figure 9. The Evans classification of intertrochanteric fractures. In stable fracture patterns, the posteromedial cortex remains intact or has minimal comminution, making it possible to obtain and maintain a reduction. Unstable fracture patterns, conversely, are characterized by greater comminution of the posteromedial cortex. The reverse obliquity pattern is inherently unstable because of the tendency for medial displacement of the femoral shaft. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

Basicervical Fractures

• Basicervical neck fractures are located just proximal to or along the intertrochanteric line (Fig. 10).

• These fractures are usually extracapsular.

• They are at greater risk for osteonecrosis than the more distal intertrochanteric fractures.

• They lack the cancellous interdigitation seen with fractures through the intertrochanteric region and are more likely to sustain rotation of the femoral head during implant insertion.

Figure 10. Basicervical neck fractures are located just proximal to or along the intertrochanteric line. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

 

Reverse Obliquity Fractures

• Reverse obliquity intertrochanteric fractures are unstable fractures characterized by an oblique fracture line extending from the medial cortex proximally to the lateral cortex distally (Fig. 11).

• The location and direction of the fracture line result in a tendency to medial displacement from the pull of the adductor muscles.

TREATMENT

 

 

Nonoperative

• This is indicated only for patients who are at extreme medical risk for surgery; it may also be considered for demented nonambulatory patients with mild hip pain.

• Early bed to chair mobilization is important to avoid increased risks and complications of prolonged recumbency, including poor pulmonary toilet, atelectasis, venous stasis, and pressure ulceration.

• Resultant hip deformity is both expected and accepted.

• This is associated with a higher mortality rate than operative treatment.

Operative

• The goal is stable internal fixation to allow early mobilization and full weight-bearing ambulation. Stability of fracture fixation depends on:
• Bone quality.
• Fracture pattern.
• Fracture reduction.
• Implant design.
• Implant placement.

Timing of Surgery

• Surgery should be performed in a timely fashion, once the patient has been medically stabilized.

Fixation Implants

SLING HIP SCREW

• This is the most commonly used device for both stable and unstable fracture patterns. It is available in plate angles from 130 to 150 degrees (Fig. 12).

Figure 11. Anteroposterior x-ray demonstrating a reverse obliquity right intertrochanteric fracture. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

Figure 12. X-ray of a sliding hip screw. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

• The most important technical aspects of screw insertion are (1) placement within 1 cm of subchondral bone to provide secure fixation and (2) central position in the femoral head.

• The tip-apex distance can be used to determine lag screw position within the femoral head. This measurement, expressed in millimeters, is the sum of the distances from the tip of the lag screw to the apex of the femoral head on both the AP and lateral radiographic views (after controlling for radiographic magnification) (Fig. 13). The sum should be <25 mm to minimize the risk of lag screw cutout.

• Biomechanical and clinical studies have showo advantage of four screws over two to stabilize the sideplate.

• At surgery, the surgeon must be prepared to deal with residual varus angulation, posterior sag, or malrotation.

Figure 13. The tip-apex distance (TAD), expressed in millimeters, is the sum of the distances from the tip of the lag screw to the apex of the femoral head on both the anteroposterior and lateral radiographic views. (From Baumgaertner MR, Chrostowski JH, Levy RN. Intertrochanteric hip fractures. In: Browner BD, Levine AM, Jupiter JB, Trafton PG, eds. Skeletal Trauma, vol. 2. Philadelphia: WB Saunders, 1992:1833–1881.)

• A 4% to 12% incidence of loss of fixation is reported, most commonly with unstable fracture patterns.

• Most failures of fixation are attributable to technical problems of screw placement and/or inadequate impaction of the fracture fragments at the time of screw insertion.

INTRAMEDULLARY HIP SCREW

• This implant combines the features of a sliding hip screw (SHS) and an intramedullary nail (Fig. 14).

• Advantages are both technical and mechanical: Theoretically, these implants can be inserted in a closed manner with limited fracture exposure, decreased blood loss, and less tissue damage than an SHS. In addition, these devices are subjected to a lower bending moment than the SHS owing to their intramedullary location.

• Use of the intramedullary hip screw limits the amount of fracture collapse, compared with an SHS.

Figure 14. Reverse obliquity fracture stabilized with a cephalomedullary nail. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

• Most studies have demonstrated no clinical advantage of the intramedullary hip screw compared with the SHS in stable fracture patterns.

• Use of intramedullary hip screws has been most effective in intertrochanteric fractures with subtrochanteric extension and in reverse obliquity fractures.

• Use of older design intramedullary hip screws has been associated with an increased risk of femur fracture at the nail tip or distal locking screw insertion point.

Prosthetic Replacement

• This has been used successfully for patients in whom open reduction and internal fixation have failed and who are unsuitable candidates for repeat internal fixation.

• A calcar replacement hemiarthroplasty is needed because of the level of the fracture.

• Primary prosthetic replacement for comminuted, unstable intertrochanteric fractures has yielded up to 94% good functional results.

• Disadvantages include morbidity associated with a more extensive operative procedure, the internal fixation problems with greater trochanteric reattachment, and the risk of postoperative prosthetic dislocation.

External Fixation

• This is not commonly considered for the treatment of intertrochanteric femur fractures.

• Early experiences with external fixation for intertrochanteric fractures were associated with postoperative complications such as pin loosening, infection, and varus collapse.

• Recent studies have reported good results using hydroxyapatite-coated pins.

Special Considerations

• With use of an SHS, large posteromedial fragments in younger individuals should receive fixation with cerclage wires or a lag screw to restore the posteromedial buttress.

• With use of an SHS, greater trochanteric displacement should be fixed utilizing tension band techniques.

• Basicervical fractures should be treated with an SHS or IM nail with a supplemental antirotation screw or pin during implant insertion.

• Reverse obliquity fractures are best treated as subtrochanteric fractures.

• Ipsilateral fractures of the femoral shaft, although more common in association with femoral neck fractures, should be ruled out when the injury is caused by high-energy trauma.

Rehabilitation

• Early patient mobilization with weight bearing as tolerated ambulation is indicated.

COMPLICATIONS

• Loss of fixation: This most commonly results from varus collapse of the proximal fragment with cutout of the lag screw from the femoral head; the incidence of fixation failure is reported to be as high as 20% in unstable fracture patterns. Lag screw cutout from the femoral head generally occurs within 3 months of surgery and is usually caused by one the following:

• Eccentric placement of the lag screw within the femoral head.

• Improper reaming that creates a second channel.

• Inability to obtain a stable reduction.

• Excessive fracture collapse such that the sliding capacity of the device is exceeded.

• Inadequate screw-barrel engagement, which prevents sliding.

• Severe osteopenia, which precludes secure fixation.

• Management choices include: (1) acceptance of the deformity; (2) revision open reduction and internal fixation, which may require methylmethacrylate; and (3) conversion to prosthetic replacement. Acceptance of the deformity should be considered in marginal ambulators who are a poor surgical risk. Revision open reduction and internal fixation are indicated in younger patients, whereas conversion to prosthetic replacement (unipolar, bipolar, or total hip replacement) is preferred in elderly patients with osteopenic bone.

• Nonunion: Rare, occurring in less than 2% of patients, especially in patients with unstable fracture patterns. The diagnosis should be suspected in a patient with persistent hip pain and radiographs revealing a persistent radiolucency at the fracture site 4 to 7 months after fracture fixation. With adequate bone stock, repeat internal fixation combined with a valgus osteotomy and bone grafting may be considered. In most elderly individuals, conversion to a calcar replacement prosthesis is preferred.

• Malrotation deformity: This results from internal rotation of the distal fragment at the time of internal fixation. When it is severe and interferes with ambulation, revision surgery with plate removal and rotational osteotomy of the femoral shaft should be considered.

• With full-length intramedullary nails, impingement of the distal aspect of the nail on the anterior femoral cortex can occur, secondary to a mismatch of the nail curvature and femoral bow.

• With dual screw trochanteric nails, failure can result from the “Z effect,” with the most proximal screw penetrating the hip joint and the distal screw backing out of the femoral head.

• Osteonecrosis of the femoral head: This is rare following intertrochanteric fracture.

• Lag screw-sideplate separation.
• Lag screw migration into the pelvis.

• Laceration of the superficial femoral artery by a displaced lesser trochanter fragment.

Greater Trochanteric Fractures

• Isolated greater trochanteric fractures, although rare, typically occur in older patients as a result of a direct blow.

• Treatment of greater trochanteric fractures is usually nonoperative.

• Operative management can be considered in younger, active patients who have a widely displaced greater trochanter.

• Tension band wiring of the displaced fragment and the attached abductor muscles is the preferred technique.

Lesser Trochanteric Fractures

• These are most common in adolescence, typically secondary to forceful iliopsoas contracture.

• In the elderly, isolated lesser trochanter fractures have been recognized as pathognomonic for pathologic lesions of the proximal femur.

Subtrochanteric Fractures

ANATOMY

• A subtrochanteric femur fracture is a fracture between the lesser trochanter and a point 5 cm distal to the lesser trochanter.

• The subtrochanteric segment of the femur is the site of very high biomechanical stresses. The medial and posteromedial cortices are the sites of high compressive forces, whereas the lateral cortex experiences high tensile forces (Fig. 15).

• The subtrochanteric area of the femur is composed mainly of cortical bone. Therefore, there is less vascularity in this region, and the potential for healing is diminished as compared with intertrochanteric fractures.

• The deforming muscle forces on the proximal fragment include abduction by the gluteus, external rotation by the short rotators, and flexion by the psoas. The distal fragment is pulled proximally and into varus by the adductors (Fig. 16).

MECHANISM OF INJURY

• Low-energy mechanisms: Elderly individuals sustain a minor fall in which the fracture occurs through weakened bone.

• High-energy mechanisms: Younger adults with normal bone sustain injuries related to motor vehicle accidents, gunshot wounds, or falls from a height.

• Pathologic fracture: The subtrochanteric region is also a frequent site for pathologic fractures, accounting for 17% to 35% of all subtrochanteric fractures.

• Ten percent of high-energy subtrochanteric fractures result from gunshot injuries.

CLINICAL EVALUATION

• Patients involved in high-energy trauma should receive full trauma evaluation.

• Patients typically are unable to walk and have varying degrees of gross deformity of the lower extremity.

• Hip motion is painful, with tenderness to palpation and swelling of the proximal thigh.

• Because substantial forces are required to produce this fracture pattern in younger patients, associated injuries should be expected and carefully evaluated.

• Field dressings or splints should be completely removed, with the injury site examined for evidence of soft tissue compromise or open injury.

• The thigh represents a compartment into which volume loss from hemorrhage may be significant; monitoring for hypovolemic shock should thus be undertaken, with invasive monitoring as necessary.

• Provisional splinting (i.e., traction pin) until definitive fixation should be performed to limit further soft tissue damage and hemorrhage.

• A careful neurovascular examination is important to rule out associated injuries, although neurovascular compromise related to the subtrochanteric fracture is uncommon.

Figure 15. Koch’s diagram showing the compression stress on the medial side and the tension stress on the lateral side of the proximal femur. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

RADIOGRAPHIC EVALUATION

• An anteroposterior (AP) view of the pelvis and AP and lateral views of the hip and femur should be obtained.

• One should assess the entire femur including the knee.

• Associated injuries should be evaluated, and if suspected, appropriate radiographic studies ordered.

• A contralateral scanogram is helpful to determine femoral length in highly comminuted fractures.

CLASSIFICATION

Fielding (Fig. 17)

This is based on the location of the primary fracture line in relation to the lesser trochanter.

Type I:	At the level of the lesser trochanter
Type II:	<2.5 cm below the lesser trochanter
Type III:	2.5 to 5 cm below the lesser trochanter

 

Figure 16. The deforming force by the unopposed pull of the iliopsoas causes the proximal femur in flexion and external rotation. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

Figure 17. Fielding classification of subtrochanteric fractures. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

Seinsheimer (Fig. 18)

Figure 18. Seinsheimer classification of subtrochanteric fractures. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Greenв’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

This is based on the number of major bone fragments and the location and shape of the fracture lines.

 

Russell-Taylor (Fig. 19)

Figure 19. Russell-Taylor classification of subtrochanteric fractures. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

This was created in response to the development of first- and second-generation interlocked nails.

 

OTA Classification of Subtrochanteric Fractures

See Fracture and Dislocation Compendium at http://www.ota.org/compendium/index.htm.

TREATMENT

Nonoperative

• This involves skeletal traction in the 90/90-degree position followed by spica casting or cast bracing.

• This is reserved only for those elderly individuals who are not operative candidates and for children.

• Nonoperative treatment generally results in increased morbidity and mortality in adults, as well as ionunion, delayed union, and malunion with varus angulation, rotational deformity, and shortening.

Operative

• Operative treatment is indicated in most subtrochanteric fractures

Implants

INTERLOCKING NAIL

• First-generation (centromedullary) nails are indicated for subtrochanteric fractures with both trochanters intact.

• Second-generation cephalomedullary (i.e., reconstruction) nails are indicated for fractures with loss of the posteromedial cortex.

• Second-generatioails can also be used for fractures extending into the piriformis fossae, but they are technically more difficult to insert.

• Nails that utilize either a piriformis or greater trochanteric starting point can be used.

• With use of an intramedullary nail, one must monitor for the nail exiting posteriorly out of the proximal fragment. One must also monitor for the common malalignment of varus and flexion of the proximal fragment.

NINETY-FIVE-DEGREE FIXED ANGLE DEVICE

• The 95-degree fixed angle plates are best suited for fractures involving both trochanters; an accessory screw can be inserted beneath the fixed angle blade or screw into the calcar to increase proximal fixation (Fig. 20).

• These devices function as a tension band when the posteromedial cortex is restored.

• A dynamic condylar screw is technically easier to insert than a blade plate.

• One must take care not to devitalize the fracture fragments during fracture reduction and fixation.

SLIDING HIP SCREW

• This is generally not indicated for subtrochanteric fractures except those with intertrochanteric extension.

Bone Grafting

Figure 20. A subtrochanteric fracture fixed with a fixed angle blade plate and bone graft on the posteromedial cortex. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

• Closed reduction techniques have decreased the need for bone grafting, because fracture fragments are not devascularized to the same extent as in open reduction.

• If needed, it should be inserted through the fracture site, usually before plate application.

Open Subtrochanteric Fractures

• These are rare, almost always associated with either penetrating injury or high-energy trauma from a motor vehicle accident or a fall from a height.

• Treatment consists of immediate surgical debridement and osseous stabilization.

COMPLICATIONS

Loss of Fixation

• With plate and screw devices, implant failure usually occurs secondary to screw cutout from the femoral head and neck in patients with osteopenic bone or plate breakage.

• With interlocked nails, loss of fixation is commonly related to failure to lock the device statically, comminution of the entry portal, or use of smaller-diameter nails.

• Fixation failure involves removal of hardware, revision internal fixation with either plate and screws or an interlocked nail, and bone grafting.

Nonunion

• This may be evident by a patient’s inability to resume full weight bearing within 4 to 6 months.

• Symptoms are pain about the proximal thigh and pain on attempted weight bearing.

• Nonunion usually occurs in the femoral shaft portion of the fracture.

• Nonunions that develop following intramedullary nailing can be treated by implant removal followed by repeat reaming and placement of a larger-diameter intramedullary nail.

Malunion

• The patient may complain of a limp, leg length discrepancy, or rotational deformity.

• Coxa varus is mainly the result of the uncorrected abduction deformity of the proximal segment caused by the hip abductors.

• A valgus osteotomy and revision internal fixation with bone grafting are the usual treatment for a varus malreduction.

• Leg length discrepancy is a complex problem that is more likely to occur following a fracture with extensive femoral shaft comminution stabilized with a dynamically locked rather than a statically locked nail.

• Malrotation may occur with use of plate and screws or an intramedullary nail if the surgeon is not alert to this potential complication.

Femoral Shaft

• A femoral shaft fracture is a fracture of the femoral diaphysis occurring between 5 cm distal to the lesser trochanter and 5 cm proximal to the adductor tubercle.

EPIDEMIOLOGY

• There is an age- and gender-related bimodal distribution of fractures.

• Femoral shaft fractures occur most frequently in young men after high-energy trauma and elderly women after a low-energy fall.

ANATOMY

• The femur is the largest tubular bone in the body and is surrounded by the largest mass of muscle. An important feature of the femoral shaft is its anterior bow.

• The medial cortex is under compression, whereas the lateral cortex is under tension.

• The isthmus of the femur is the region with the smallest intramedullary (IM) diameter; the diameter of the isthmus affects the size of the IM nail that can be inserted into the femoral shaft.

• The femoral shaft is subjected to major muscular deforming forces (Fig. 21):

• Abductors (gluteus medius and minimus): They insert on the greater trochanter and abduct the proximal femur following subtrochanteric and proximal shaft fractures.

• Iliopsoas: It flexes and externally rotates the proximal fragment by its attachment to the lesser trochanter.

• Adductors: They span most shaft fractures and exert a strong axial and varus load to the bone by traction on the distal fragment.

• Gastrocnemius: It acts on distal shaft fractures and supracondylar fractures by flexing the distal fragment.

• Fascia lata: It acts as a tension band by resisting the medial angulating forces of the adductors.

• The thigh musculature is divided into three distinct fascial compartments (Fig. 22):

• Anterior compartment: This is composed of the quadriceps femoris, iliopsoas, sartorius, and pectineus, as well as the femoral artery, vein, and nerve, and the lateral femoral cutaneous nerve.

Figure 21. Deforming muscle forces on the femur; abductors (A), iliopsoas (B), adductors (C), and gastrocnemius origin (D). The medial angulating forces are resisted by the fascia lata (E). Potential sites of vascular injury after fracture are at the adductor hiatus and the perforating vessels of the profunda femoris. (From Bucholz RW, Heckman JD, eds. Rockwood and Green’s Fractures in Adults, 5th ed. Baltimore: Lippincott Williams & Wilkins, 2002.)

Figure 22. Cross-sectional diagram of the thigh demonstrates the three major compartments. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

• Medial compartment: This contains the gracilis, adductor longus, brevis, magnus, and obturator externus muscles along with the obturator artery, vein, and nerve, and the profunda femoris artery.

• Posterior compartment: This includes the biceps femoris, semitendinosus, and semimembranosus, a portion of the adductor magnus muscle, branches of the profunda femoris artery, the sciatic nerve, and the posterior femoral cutaneous nerve.

• Because of the large volume of the three fascial compartments of the thigh, compartment syndromes are much less common than in the lower leg.

• The vascular supply to the femoral shaft is derived mainly from the profunda femoral artery. The one to two nutrient vessels usually enter the bone proximally and posteriorly along the linea aspera. This artery then arborizes proximally and distally to provide the endosteal circulation to the shaft. The periosteal vessels also enter the bone along the linea aspera and supply blood to the outer one-third of the cortex. The endosteal vessels supply the inner two-thirds of the cortex.

• Following most femoral shaft fractures, the endosteal blood supply is disrupted, and the periosteal vessels proliferate to act as the primary source of blood for healing. The medullary supply is eventually restored late in the healing process.

• Reaming may further obliterate the endosteal circulation, but it returns fairly rapidly, in 3 to 4 weeks.

• Femoral shaft fractures heal readily if the blood supply is not excessively compromised. Therefore, it is important to avoid excessive periosteal stripping, especially posteriorly, where the arteries enter the bone at the linea aspera.

MECHANISM OF INJURY

• Femoral shaft fractures in adults are almost always the result of high-energy trauma. These fractures result from motor vehicle accident, gunshot injury, or fall from a height.

• Pathologic fractures, especially in the elderly, commonly occur at the relatively weak metaphyseal-diaphyseal junction. Any fracture that is inconsistent with the degree of trauma should arouse suspicion for pathologic fracture.

• Stress fractures occur mainly in military recruits or runners. Most patients report a recent increase in training intensity just before the onset of thigh pain.

CLINICAL EVALUATION

• Because these fractures tend to be the result of high-energy trauma, a full trauma survey is indicated.

• The diagnosis of femoral shaft fracture is usually obvious, with the patient presenting nonambulatory with pain, variable gross deformity, swelling, and shortening of the affected extremity.

• A careful neurovascular examination is essential, although neurovascular injury is uncommonly associated with femoral shaft fractures.

• Thorough examination of the ipsilateral hip and knee should be performed, including systematic inspection and palpation. Range-of-motion or ligamentous testing is often not feasible in the setting of a femoral shaft fracture and may result in displacement. Knee ligament injuries are common, however, and need to be assessed after fracture fixation.

• Major blood loss into the thigh may occur. The average blood loss in one series was greater than 1200 mL, and 40% of patients ultimately required transfusions. Therefore, a careful preoperative assessment of hemodynamic stability is essential, regardless of the presence or absence of associated injuries.

ASSOCIATED INJURIES

• Associated injuries are common and may be present in up to 5% to 15% of cases, with patients presenting with multisystem trauma, spine, pelvis, and ipsilateral lower extremity injuries.

• Ligamentous and meniscal injuries of the ipsilateral knee are present in 50% of patients with closed femoral shaft fractures.

RADIOGRAPHIC EVALUATION

• Anteroposterior (AP) and lateral views of the femur, hip, and knee as well as an AP view of the pelvis should be obtained.

• The radiographs should be critically evaluated to determine the fracture pattern, the bone quality, the presence of bone loss, associated comminution, the presence of air in the soft tissues, and the amount of fracture shortening.

• One must evaluate the region of the proximal femur for evidence of an associated femoral neck or intertrochanteric fracture.

• If a computed tomography scan of the abdomen and/or pelvis is obtained for other reasons, this should be reviewed because it may provide evidence of injury to the ipsilateral acetabulum or femoral neck.

CLASSIFICATION

Descriptive

• Open versus closed injury
• Location: proximal, middle, or distal one-third

• Location: isthmal, infraisthmal or supracondylar
• Pattern: spiral, oblique, or transverse
• Comminuted, segmental, or butterfly fragment
• Angulation or rotational deformity
• Displacement: shortening or translation

Winquist and Hansen (Fig. 23)

• This is based on fracture comminution.

• It was used before routine placement of statically locked IM nails.

Type I:	Minimal or no comminution
Type II:	Cortices of both fragments at least 50% intact
Type III:	50% to 100% cortical comminution
Type VI:	Circumferential comminution with no cortical contact

OTA Classification of Femoral Shaft Fractures

See Fracture and Dislocation Compendium at http://www.ota.org/compendium/index.htm.

TREATMENT

Nonoperative

Skeletal Traction

• Currently, closed management as definitive treatment for femoral shaft fractures is largely limited to adult patients with such significant medical comorbidities that operative management is contraindicated.

• The goal of skeletal traction is to restore femoral length, limit rotational and angular deformities, reduce painful spasms, and minimize blood loss into the thigh.

Figure 23. Winquist and Hansen classification of femoral shaft fractures. (From Browner BD, Jupiter JB, Levine AM, et al. Skeletal Trauma. Philadelphia: WB Saunders, 1992:1537.)

• Skeletal traction is usually used as a temporizing measure before surgery to stabilize the fracture and prevent fracture shortening.

• Twenty to 40 lb of traction is usually applied and a lateral radiograph checked to assess fracture length.

• Distal femoral pins should be placed in an extracapsular location to avoid the possibility of septic arthritis. Proximal tibia pins are typically positioned at the level of the tibial tubercle and are placed in a bicortical location.

• Safe pin placement is usually from medial to lateral at the distal femur (directed away from the femoral artery) and from lateral to medial at the proximal tibia (directed away from the peroneal nerve).

• Problems with use of skeletal traction for definitive fracture treatment include knee stiffness, limb shortening, prolonged hospitalization, respiratory and skin ailments, and malunion.

Operative

• Operative stabilization is the standard of care for most femoral shaft fractures.

• Surgical stabilization should occur within 24 hours, if possible.

• Early stabilization of long bone injuries appears to be particularly important in the multiply injured patient.

Intramedullary (IM) Nailing

• This is the standard of care for femoral shaft fractures.

• Its IM location results in lower tensile and shear stresses on the implant than plate fixation. Benefits of IM nailing over plate fixation include less extensive exposure and dissection, lower infection rate, and less quadriceps scarring.

• Closed IM nailing in closed fractures has the advantage of maintaining both the fracture hematoma and the attached periosteum. If reaming is performed, these elements provide a combination of osteoinductive and osteoconductive materials to the site of the fracture.

• Other advantages include early functional use of the extremity, restoration of length and alignment with comminuted fractures, rapid and high union (>95%), and low refracture rates.

Antegrade Inserted Intramedullary (IM) Nailing

• Surgery can be performed on a fracture table or on a radiolucent table with or without skeletal traction.

• The patient can be positioned supine or lateral. Supine positioning allows unencumbered access to the entire patient. Lateral positioning facilitates identification of the piriformis starting point but may be contraindicated in the presence of pulmonary compromise.

• One can use either a piriformis fossa or greater trochanteric starting point. The advantage of a piriformis starting point is that it is in line with the medullary canal of the femur. However, it is easier to locate the greater trochanteric starting point. Use of a greater trochanteric starting point requires use of a nail with a valgus proximal bow to negotiate the off starting point axis.

• With the currently available nails, the placement of large diameter nails with an intimate fit along a long length of the medullary canal is no longer necessary.

• The role of unreamed IM nailing for the treatment of femoral shaft fractures remains unclear. The potentially negative effects of reaming for insertion of IM nails include elevated IM pressures, elevated pulmonary artery pressures, increased fat embolism, and increased pulmonary dysfunction. The potential advantages of reaming rate include the ability to place a larger implant, increased union, and decreased hardware failure.

• All IM nails should be statically locked to maintain femoral length and control rotation. The number of distal interlocking screws necessary to maintain the proper length, alignment, and rotation of the implant bone construct depends on numerous factors including fracture comminution, fracture location, implant size, patient size, bone quality, and patient activity.

Retrograde Inserted Intramedullary (IM) Nailing

• The major advantage with a retrograde entry portal is the ease in properly identifying the starting point.

• Relative indications include:
• Ipsilateral injuries such as femoral neck, pertrochanteric, acetabular, patellar, or tibial shaft fractures.

• Bilateral femoral shaft fractures.
• Morbidly obese patient.
• Pregnant woman.
• Periprosthetic fracture above a total knee arthroplasty.

• Ipsilateral through knee amputation in a patient with an associated femoral shaft fracture.

• Contraindications include:
• Restricted knee motion <60 degrees.
• Patella baja.
• The presence of an associated open traumatic wound, secondary to the risk of intraarticular knee sepsis.

External Fixation

• Use as definitive treatment for femoral shaft fractures has limited indications.

• Its use is most often provisional.

• Advantages include the following:
• The procedure is rapid; A temporary external fixator can be applied in less than 30 minutes.

• The vascular supply to the femur is minimally damaged during application.

• No additional foreign material is introduced in the region of the fracture.

• It allows access to the medullary canal and the surrounding tissues in open fractures with significant contamination.

• Disadvantages: Most are related to use of this technique as a definitive treatment and include:

• Pin tract infection.
• Loss of knee motion.
• Angular malunion and femoral shortening.

• Limited ability to adequately stabilize the femoral shaft.

• Potential infection risk associated with conversion to an IM nail.

• Indications for use of external fixation include:

• Use as a temporary bridge to IM nailing in the severely injured patient.

• Ipsilateral arterial injury that requires repair.

• Patients with severe soft tissue contamination in whom a second debridement would be limited by other devices.

Plate Fixation

Plate fixation for femoral shaft stabilization has decreased with the use of IM nails.

• Advantages to plating include:
• Ability to obtain an anatomic reduction in appropriate fracture patterns.

• Lack of additional trauma to remote locations such as the femoral neck, the acetabulum, and the distal femur.

• Disadvantages compared with IM nailing include:

• Need for an extensive surgical approach with its associated blood loss, risk of infection, and soft tissue insult. This can result in quadriceps scarring and its effects on knee motion and quadriceps strength.

• Decreased vascularization beneath the plate and the stress shielding of the bone spanned by the plate.

• The plate is a load bearing implant; therefore, higher rate of implant failure.

• Indications include:
• Extremely narrow medullary canal where IM nailing is impossible or difficult.

• Fractures that occur adjacent to or through a previous malunion.

• Obliteration of the medullary canal due to infection or previous closed management.

• Fractures that have associated proximal or distal extension into the pertrochanteric or condylar regions.

• In patients with an associated vascular injury, the exposure for the vascular repair frequently involves a wide exposure of the medial femur. If rapid femoral stabilization is desired, a plate can be applied quickly through the medial open exposure.

• An open or a submuscular technique may be applicable.

• As the fracture comminution increases, so should the plate length such that at least four to five screw holes of plate length are present on each side of the fracture.

• The routine use of cancellous bone grafting in plated femoral shaft fractures is questionable if indirect reduction techniques are used.

Femur Fracture in Multiply Injured Patient

• The impact of femoral nailing and reaming is controversial in the polytrauma patient.

• In a specific subpopulation of patients with multiple injuries, early IM nailing is associated with elevation of certain proinflammatory markers.

• It has been recommended that early external fixation of long bone fractures followed by delayed IM nailing may minimize the additional surgical impact in patients at high risk for developing complications (i.e., patients in extremis or underresuscitated).

Ipsilateral Fractures of the Proximal or Distal Femur

• Concomitant femoral neck fractures occur in 3% to 10% of patients with femoral shaft fractures. Options for operative fixation include antegrade IM nailing with multiple screw fixation of the femoral neck, retrograde femoral nailing with multiple screw fixation of the femoral neck, and compression plating with screw fixation of the femoral neck. The sequence of surgical stabilization is controversial.
• Ipsilateral fractures of the distal femur may exist as a distal extension of the shaft fracture or as a distinct fracture. Options for fixation include fixation of both fractures with a single plate, fixation of the shaft and distal femoral fractures with separate plates, IM nailing of the shaft fracture with plate fixation of the distal femoral fracture, or interlocked IM nailing spanning both fractures (high supracondylar fractures).

Open Femoral Shaft Fractures

• These are typically the result of high-energy trauma.

• Patients frequently have multiple other orthopaedic injuries and involvement of several organ systems.

• Treatment is emergency debridement with skeletal stabilization.

• Stabilization can usually involve placement of a reamed IM nail.

REHABILITATION

• Early patient mobilization out of bed is recommended.

• Early range of knee motion is indicated.

• Weight bearing on the extremity is guided by a number of factors including the patient’s associated injuries, soft tissue status, and the location of the fracture.

COMPLICATIONS

• Nerve injury: This is uncommon because the femoral and sciatic nerves are encased in muscle throughout the length of the thigh. Most injuries occur as a result of traction or compression during surgery.

• Vascular injury: This may result from tethering of the femoral artery at the adductor hiatus.

• Compartment syndrome: This occurs only with significant bleeding. It presents as pain out of proportion, tense thigh swelling, numbness or paresthesias to medial thigh (saphenous nerve distribution), or painful passive quadriceps stretch.

• Infection (<1% incidence in closed fractures): The risk is greater with open versus closed IM nailing. Grades I, II, and IIIA open fractures carry a low risk of infection with IM nailing, whereas fractures with gross contamination, exposed bone, and extensive soft tissue injury (grades IIIB, IIIC) have a higher risk of infection regardless of treatment method.

• Refracture: Patients are vulnerable during early callus formation and after hardware removal. It is usually associated with plate or external fixation.
• Nonunion and delayed union: This is unusual. Delayed union is defined as healing taking longer than 6 months, usually related to insufficient blood supply (i.e., excessive periosteal stripping), uncontrolled repetitive stresses, infection, and heavy smoking. Nonunion is diagnosed once the fracture has no further potential to unite.

• Malunion: This is usually varus, internal rotation, and/or shortening owing to muscular deforming forces or surgical technique.

• Fixation device failure: This results from nonunion or “cycling” of device, especially with plate fixation.

• Heterotopic ossification may occur.

Distal Femur

EPIDEMIOLOGY

• Distal femoral fractures account for about 7% of all femur fractures.

• If hip fractures are excluded, one-third of femur fractures involve the distal portion.

• A bimodal age distribution exists, with a high incidence in young adults from high-energy trauma, such as motor vehicle or motorcycle accidents or falls from a height, and a second peak in the elderly from minor falls.

• Open fractures occur in 5% to 10% of all distal femur fractures.

ANATOMY

• The distal femur includes both the supracondylar and condylar regions (Fig. 24).

• The supracondylar area of the femur is the zone between the femoral condyles and the junction of the metaphysis with the femoral shaft. This area comprises the distal 10 to 15 cm of the femur.

• The distal femur broadens from the cylindric shaft to form two curved condyles separated by an intercondylar groove.

• The medial condyle extends more distally and is more convex than the lateral femoral condyle. This accounts for the physiologic valgus of the femur.
• When viewing the lateral femur, the femoral shaft is aligned with the anterior half of the lateral condyle (Fig. 25).

• When viewing the distal surface of the femur end on, the condyles are wider posteriorly, thus forming a trapezoid.

• Normally, the knee joint is parallel to the ground. On average, the anatomic axis (the angle between the shaft of the femur and the knee joint) has a valgus angulation of 9 degrees (range, 7 to 11 degrees) (Fig. 26).

• Deforming forces from muscular attachments cause characteristic displacement patterns (Fig. 27).

• Gastrocnemius: This flexes the distal fragment, causing posterior displacement and angulation.

• Quadriceps and hamstrings: They exert proximal traction, resulting in shortening of the lower extremity.

MECHANISM OF INJURY

• Most distal femur fractures are the result of a severe axial load with a varus, valgus, or rotational force.

• In young adults, this force is typically the result of high-energy trauma such as motor vehicle collision or fall from a height.

• In the elderly, the force may result from a minor slip or fall onto a flexed knee.

CLINICAL EVALUATION

• Patients typically are unable to ambulate with pain, swelling, and variable deformity in the lower thigh and knee.

Figure 24. Schematic drawing of the distal femur. (Adapted from Wiss D. Master Techniques in Orthopaedic Surgery. Philadelphia: Lippincott-Raven, 1998.)

Figure 25. Anatomy of the distal femur. (A) Anterior view. (B) Lateral view. The shaft of the femur is aligned with the anterior half of the lateral condyle. (C) Axial view. The distal femur is trapezoidal. The anterior surface slopes downward from lateral to medial, the lateral wall inclines 10 degrees, and the medial wall inclines 25 degrees. (Adapted from Wiss D, Watson JT, Johnson EE. Fractures of the knee. In: Rockwood CA, Green DP, Bucholz RW, et al., eds. Rockwood and Green’s Fractures in Adults, 4th ed. Philadelphia: Lippincott-Raven, 1996.)

• Assessment of neurovascular status is mandatory. The proximity of the neurovascular structures to the fracture area is an important consideration. Unusual and tense swelling in the popliteal area and the usual signs of pallor and lack of pulse suggest rupture of a major vessel.

Figure 26. Alignment of the lower extremity. The knee joint is parallel to the ground. The knee joint is in 9 degree valgus to the knee joint. (Adapted from Browner BD, Levine AM, Jupiter JB. Skeletal Trauma: Fractures, Dislocations, Ligamentous Injuries, 2nd ed. Philadelphia: WB Saunders, 1997.)

• Compartment syndrome of the thigh is uncommon and is associated with major bleeding into the thigh.

• Examination of the ipsilateral hip, knee, leg, and ankle is essential, especially in the obtunded or polytraumatized patient.

• When a distal femoral fracture is associated with an overlying laceration or puncture wound, 50 mL or more of saline should be injected into the knee from a remote location to determine continuity with the wound.

Figure 27. Lateral view showing muscle attachments and resulting deforming forces. These result in posterior displacement and angulation at the fracture site. (Adapted from Browner BD, Levine AM, Jupiter JB. Skeletal Trauma: Fractures, Dislocations, Ligamentous Injuries, 2nd ed. Philadelphia: WB Saunders, 1997.)

 

RADIOGRAPHIC EVALUATION

• Anteroposterior, lateral, and two 45-degree oblique radiographs of the distal femur should be obtained.

• Radiographic evaluation should include the entire femur.

• Traction views may be helpful to better determine the fracture pattern.

• Contralateral views may be helpful for comparison and serve as a template for preoperative planning.

• Complex intraarticular fractures and osteochondral lesions may require additional imaging with computed tomography to assist in completing the diagnostic assessment and preoperative planning.

• Magnetic resonance imaging may be of value in evaluating associated injuries to ligamentous or meniscal structures.

• Arteriography may be indicated with dislocation of the knee, because 40% of dislocations are associated with vascular disruption. The reason is that the popliteal vascular bundle is tethered proximally at the adductor hiatus and distally at the soleus arch. By contrast, the incidence of vascular disruption with isolated supracondylar fractures is between 2% and 3%.

CLASSIFICATION

Descriptive

• Open versus closed
• Location: supracondylar, intercondylar, condylar
• Pattern: spiral, oblique, or transverse
• Articular involvement
• Comminuted, segmental, or butterfly fragment
• Angulation or rotational deformity
• Displacement: shortening or translation

OTA Classification of Distal Femoral Fractures

See Fracture and Dislocation Compendium at http://www.ota.org/compendium/index.htm.

TREATMENT

Nonoperative

• Indications include nondisplaced or incomplete fractures, impacted stable fractures in elderly patients, severe osteopenia, advanced underlying medical conditions, or select gunshot injuries.

• In stable, nondisplaced fractures, treatment is mobilization of the extremity in a hinged knee brace, with partial weight bearing.

• In displaced fractures, nonoperative treatment entails a 6- to 12-week period of skeletal traction followed by bracing. The objective is not absolute anatomic reduction, but restoration of the knee joint axis to a normal relationship with the hip and ankle. Potential drawbacks include varus and internal rotation deformity, knee stiffness, and the necessity for prolonged hospitalization and bed rest.

Operative

• Most displaced distal femur fractures are best treated with operative stabilization.

• If surgery is to be delayed more than 8 hours, tibial pin traction should be considered.

• Articular fractures require anatomic reconstruction of the joint surface and fixation with interfragmentary lag screws.

• The articular segment is then reattached to the proximal segment, with an effort to restore the normal anatomic relationships. These should encompass all angular, translational, and rotational relationships.
• In patients with severe osteopenia or contralateral amputation, length may be sacrificed for fracture stability.

• With the advent of more biologic techniques of fracture stabilization, the necessity for bone grafting has diminished.

• Polymethylmethacrylate cement may be necessary in extremely osteoporotic bone to increase the fixation capability of screws.

Implants

• Screws: In most cases, they are used in addition to other fixation devices. Ioncomminuted, unicondylar fractures in young adults with good bone stock, interfragmentary screws alone can provide adequate fixation.

• Plates: To control alignment (particularly varus and valgus) of the relatively short distal articular segment, a fixed angle implant is frequently necessary.

• A 95-degree condylar blade plate: This provides excellent fracture control but is technically demanding.

• Dynamic condylar screw (DCS): This is technically easier to insert than a condylar blade plate, and interfragmentary compression is also possible through its lag screw design. Disadvantages of the DCS are the bulkiness of the device and the poorer rotational control than with the blade plate.

• Nonlocking periarticular plates (condylar buttress plates): These are used with extensive comminution or multiple intraarticular fractures. Screws may toggle within the plate holes; therefore, these plates have no inherent varus or valgus stability. This stability must therefore be provided by additional fixation devices such as a second medial plate or by the inherent stability of the bone after fixation of the fracture.

• Locking plates (with fixed angle screws): The development of locking plates made the nonlocking periarticular plate relatively obsolete. Locking plates are an alternative to the DCS and blade plate. Like the DCS and the blade plate, locking plates are fixed-angle devices. The screws lock to the plate and therefore provide angular stability to the construct.

• Intramedullary (IM) nails
• Antegrade inserted IM nail: It has limited use owing to the distal nature of the fracture. It is best used in supracondylar type fractures with a large distal segment.

• Retrograde inserted IM nail: It has the advantage of improved distal fixation. The disadvantages are the further insult to the knee joint and the potential of knee sepsis if the nailing is complicated by infection.

• External fixation
• In patients whose medical condition requires rapid fracture stabilization or in patients with major soft tissue lesions, spanning external fixation allows for rapid fracture stabilization while still allowing access to the limb and patient mobilization.

• Definitive external fixation, although rarely used, can be in the form of a unilateral half-pin fixator or a hybrid frame.

• Problems include pin tract infection, quadriceps scarring, delayed or nonunion, and loss of reduction after device removal.

Associated Vascular Injury

• The incidence is estimated to be about 2%.

• If arterial reconstruction is necessary, it should be done before definitive skeletal stabilization.

• Reduction of the fracture and temporary fixation with an external fixator or femoral distractor before vascular repair should be considered.

• Definitive fracture management can proceed after the vascular procedure if the patient’s condition allows.

• Fasciotomy of the lower leg should be performed in all cases.

Supracondylar Fractures after Total Knee Replacement

• These are rare and are related to osteopenia, rheumatoid arthritis, prolonged corticosteroid usage, anterior notching of the femur, and revision arthroplasty.

• Treatment is based on the status of the arthroplasty implants (well fixed or loose) and the patient’s preinjury function.

• In displaced fractures, options include long-stem revision, IM nailing, and plate fixation.

Postoperative Management

• The injured extremity is typically placed on a continuous passive motion device in the immediate postoperative period if the skin and soft tissues will tolerate.

• Physical therapy consists of active range-of-motion exercises and partial weight bearing with crutches 2 to 3 days after stable fixation.

• A cast brace may be used if fixation is tenuous.

• Weight bearing may be advanced with radiographic evidence of healing (6 to 12 weeks).

COMPLICATIONS

• Fixation failure: This is usually a result of one of the following: poor bone stock, patient noncompliance with postoperative care, or inadequate surgical planning and execution.

• Malunion: This usually results from unstable fixation or infection. Varus is the most common deformity. Malunion with the articular surface in extension may result in relative hyperextension of the knee, whereas malunion in flexion may result in a functional loss of full extension. Malunion resulting in functional disability may be addressed with osteotomy.

• Nonunion: This is infrequent because of the rich vascular supply to this region and the predominance of cancellous bone.

• Posttraumatic osteoarthritis: This may result as a failure to restore articular congruity, especially in younger patients. It also may reflect chondral injury at the time of trauma.

• Infection: Open fractures require meticulous debridement and copious irrigation (serial, if necessary) with intravenous antibiotics. Open injuries contiguous with the knee necessitate formal irrigation and debridement to prevent knee sepsis.

• Loss of knee motion: This is the most common complication as a result of scarring, quadriceps damage, or articular disruption during injury. If significant, it may require lysis of adhesions or quadricepsplasty for restoration of joint motion. It is best prevented by early range of motion and adequate pain control.

PATELLAR FRACTURES

Epidemiology

• Represent 1% of all skeletal injuries
• Male-to-female ratio (2:1)
• Most common age group 20 to 50 years old

• Bilateral injuries uncommon

Anatomy

• The patella is the largest sesamoid bone in the body.

• The quadriceps tendon inserts on the superior pole and the patellar ligament originates from the inferior pole of the patella.

• There are seven articular facets; the lateral facet is the largest (50% of the articular surface).

• The articular cartilage may be up to 1 cm thick.

• The medial and lateral extensor retinacula are strong longitudinal expansions of the quadriceps and insert directly onto the tibia. If these remain intact in the presence of a patella fracture, then active extension will be preserved (Fig. 28).

• The function of the patella is to increase the mechanical advantage and leverage of the quadriceps tendon, aid in nourishment of the femoral articular surface, and protect the femoral condyles from direct trauma.

• The blood supply arises from the geniculate arteries, which form an anastomosis circumferentially around the patella.

Mechanism of Injury

• Direct: Trauma to the patella may produce incomplete, simple, stellate, or comminuted fracture patterns. Displacement is typically minimal owing to preservation of the medial and lateral retinacular expansions. Abrasions over the area or open injuries are common. Active knee extension may be preserved.

• Indirect (most common): This is secondary to forcible quadriceps contraction while the knee is in a semiflexed position (e.g., in a stumbl or fall). The intrinsic strength of the patella is exceeded by the pull of the musculotendinous and ligamentous structures. A transverse fracture pattern is most commonly seen with this mechanism, with variable inferior pole comminution. The degree of displacement of the fragments suggests the degree of retinacular disruption. Active knee extension is usually lost.
• Combined direct/indirect mechanisms: These may be caused by trauma in which the patient experiences direct and indirect trauma to the knee, such as in a fall from a height.

Clinical Evaluation

• Patients typically present with limited or no ambulatory capacity with pain, swelling, and tenderness of the involved knee. A defect at the patella may be palpable.
• It is important to rule out an open fracture because these constitute a surgical emergency; this may require instillation of 50 to 70 mL saline into the knee to determine communication with overlying lacerations.

Figure 28. Soft tissue anatomy of the patella. VL, vastus lateralis; LR, lateral retinaculum; VM, vastus medialis; QT, quadriceps tendon; MR, medial retinaculum; PT, patellar tendon. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

• Active knee extension should be evaluated to determine injury to the retinacular expansions. This may be aided by decompression of hemarthrosis or intraarticular lidocaine injection.

• Associated lower extremity injuries may be present in the setting of high-energy trauma. The physician must carefully evaluate the ipsilateral hip, femur, tibia, and ankle, with appropriate radiographic evaluation, if indicated.

Radiographic Evaluation

• Anteroposterior (AP), lateral and axial (sunrise) views of the knee should be obtained.

• AP view: A bipartite patella (8% of the population) may be mistaken for a fracture; it usually occurs in the superolateral position and has smooth margins; it is bilateral in 50% of individuals.

• Lateral view: Displaced fractures usually are obvious.

• Axial view (sunrise): This may help identify osteochondral or vertical marginal fractures.

• Arthrograms, computed tomography, and magnetic resonance imaging (MRI) are usually unnecessary, but they may be used to better delineate fracture patterns, marginal fractures, or free osteochondral fragments.

CLASSIFICATION

Descriptive (Fig. 29)

• Open versus closed
• Nondisplaced versus displaced
• Pattern: stellate, comminuted, transverse, vertical (marginal), polar

• Osteochondral

OTA Classification of Patellar Fractures

Figure 29. Classification of patella fractures. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

See Fracture and Dislocation Compendium at http://www.ota.org/compendium/index.htm.

 

Treatment

Nonoperative

• Indications include nondisplaced or minimally displaced (2- to 3-mm) fractures with minimal articular disruption (1 to 2 mm). This requires an intact extensor mechanism.
• A cylinder cast or knee immobilizer is used for 4 to 6 weeks. Early weight bearing is encouraged, advancing to full weight bearing with crutches as tolerated by the patient. Early straight leg raising and isometric quadriceps strengthening exercises should be started within a few days. After radiographic evidence of healing, progressive active flexion and extension strengthening exercises are begun with a hinged knee brace initially locked in extension for ambulation.

Operative

OPEN REDUCTION AND INTERNAL FIXATION

• Indications for open reduction and internal fixation include >2-mm articular incongruity, >3-mm fragment displacement, or open fracture.

• There are multiple methods of operative fixation, including tension banding (using parallel longitudinal Kirschner wires or cannulated screws) as well as circumferential cerclage wiring. Retinacular disruption should be repaired at the time of surgery.

• Postoperatively, the patient should be placed in a splint for 3 to 6 days until skin healing, with early institution of knee motion. The patient should perform active assisted range-of-motion exercises, progressing to partial and full weight bearing by 6 weeks.

• Severely comminuted or marginally repaired fractures, particularly in older individuals, may necessitate immobilization for 3 to 6 weeks.

PATELLECTOMY

• Partial patellectomy
• Indications for partial patellectomy include the presence of a large, salvageable fragment in the presence of smaller, comminuted polar fragments in which it is believed impossible to restore the articular surface or to achieve stable fixation.

• The quadriceps or patellar tendons should be reattached without creating patella baja or alta.

• Reattachment of the patellar tendon close to the articular surface will help to prevent patellar tilt.

• Total patellectomy
• Total patellectomy is reserved for extensive and severely comminuted fractures and is rarely indicated.

• Peak torque of the quadriceps is reduced by 50%.

• Repair of medial and lateral retinacular injuries at the time of patellectomy is essential.

• After either partial or total patellectomy, the knee should be immobilized in a long leg cast at 10 degrees of flexion for 3 to 6 weeks.

Complications

• Postoperative infection: Uncommon and is related to open injuries that may necessitate serial debridements. Relentless infection may require excision of nonviable fragments and repair of the extensor mechanism.

• Fixation failure: Incidence is increased in osteoporotic bone or after failure to achieve compression at fracture site.

• Refracture (1% to 5%): Secondary to decreased inherent strength at the fracture site.

• Nonunion (2%): Most patients retain good function, although one may consider partial patellectomy for painful nonunion. Consider revision osteosynthesis in active, younger individuals.
• Osteonecrosis (proximal fragment): Associated with greater degrees of initial fracture displacement. Treatment consists of observation only, with spontaneous revascularization occurring by 2 years.

• Posttraumatic osteoarthritis: Present in more than 50% of patients in long-term studies. Intractable patellofemoral pain may require Maquet tibial tubercle advancement.
• Loss of knee motion: Secondary to prolonged immobilization or postoperative scarring.

• Painful retained hardware: May necessitate removal for adequate pain relief.

• Loss of extensor strength and extensor lag: Most patients will experience a loss of knee extension of approximately 5 degrees, although this is rarely clinically significant.

• Patellar instability

 

Tibial Plateau

EPIDEMIOLOGY

• Tibial plateau fractures constitute 1% of all fractures and 8% of fractures in the elderly.

• Isolated injuries to the lateral plateau account for 55% to 70% of tibial plateau fractures, as compared with 10% to 25% isolated medial plateau fractures and 10% to 30% bicondylar lesions.

• From 1% to 3% of these fractures are open injuries.

ANATOMY

• The tibia is the major weight-bearing bone of the leg, accounting for 85% of the transmitted load.

• The tibial plateau is composed of the articular surfaces of the medial and lateral tibial plateaus, on which are the cartilaginous menisci. The medial plateau is larger and is concave in both the sagittal and coronal axes. The lateral plateau extends higher and is convex in both sagittal and coronal planes.

• The normal tibial plateau has a 10-degree posteroinferior slope.

• The two plateaus are separated from one another by the intercondylar eminence, which is nonarticular and serves as the tibial attachment of the cruciate ligaments. Three bony prominences exist 2 to 3 cm distal to the tibial plateau. Anteriorly is the tibial tubercle on which the patellar ligament inserts. Medially, the pes anserinus serves as attachment for the medial hamstrings. Laterally, the Gerdy tubercle is the insertion site of the iliotibial band.

• The medial articular surface and its supporting medial condyle are stronger than their lateral counterparts. As a result, fractures of the lateral plateau are more common.

• Medial plateau fractures are associated with higher energy injury and more commonly have associated soft tissue injuries, such as disruptions of the lateral collateral ligament complex, lesions of the peroneal nerve, and damage to the popliteal vessels.

MECHANISM OF INJURY

• Fractures of the tibial plateau occur in the setting of varus or valgus forces coupled with axial loading. Motor vehicle accidents account for the majority of these fractures in younger individuals, but elderly patients with osteopenic bone may experience these after a simple fall.

• The direction and magnitude of the generated force, age of the patient, bone quality, and amount of knee flexion at the moment of impact determine fracture fragment size, location, and displacement:

• Young adults with strong, rigid bone typically develop split fractures and have a higher rate of associated ligamentous disruption.

• Older adults with decreased bone strength and rigidity sustain depression and split-depression fractures and have a lower rate of ligamentous injury.

• A bicondylar split fracture results from a severe axial force exerted on a fully extended knee.

CLINICAL EVALUATION

• Neurovascular examination is essential, especially with high-energy trauma. The trifurcation of the popliteal artery is tethered posteriorly between the adductor hiatus proximally and the soleus complex distally. The peroneal nerve is tethered laterally as it courses around the fibular neck.

• Hemarthrosis frequently occurs in the setting of a markedly swollen, painful knee on which the patient is unable to bear weight. Knee aspiration may reveal marrow fat.
• Direct trauma is usually evident on examination of the overlying soft tissues, and open injuries must be ruled out. Intraarticular instillation of 50 to 75 mL saline may be necessary to evaluate possible communication with overlying lacerations

• Compartment syndrome must be ruled out, particularly with higher-energy injuries.

• Assessment for ligament injury is essential.

ASSOCIATED INJURIES

• Meniscal tears occur in up to 50% of tibial plateau fractures.

• Associated ligamentous injury to the cruciate or collateral ligaments occurs in up to 30% of tibial plateau fractures.

• Young adults, whose strong subchondral bone resists depression, are at the highest risk of collateral or cruciate ligament rupture.

• Fractures involving the medial tibial plateau are associated with higher incidences of peroneal nerve or popliteal neurovascular lesions owing to higher-energy mechanisms; it is postulated that many of these represent knee dislocations that spontaneously reduced.

• Peroneal nerve injuries are caused by stretching (neurapraxia); these will usually resolve over time.

• Arterial injuries frequently represent traction induced intimal injuries presenting as thrombosis; only rarely do they present as transection injuries secondary to laceration or avulsion.

RADIOGRAPHIC EVALUATION

• Anteroposterior and lateral views supplemented by 40-degree internal (lateral plateau) and external rotation (medial plateau) oblique projections should be obtained.

• A 10- to 5-degree caudally tilted plateau view can be used to assess articular step-off.

• Avulsion of the fibular head, the Segond sign (lateral capsular avulsion) and Pellegrini-Steata lesion (calcification along the insertion of the medial collateral ligament) are all signs of associated ligamentous injury.

• A physician-assisted traction view is often helpful in higher-energy injuries with severe impaction and metadiaphyseal fragmentation to delineate the fracture pattern better and to determine the efficacy of ligamentotaxis for fracture reduction.

• Stress views, preferably with the patient under sedation or anesthesia and with fluoroscopic image intensification, are occasionally useful for the detection of collateral ligament ruptures.

• Computed tomography with two- or three-dimensional reconstruction is useful for delineating the degree of fragmentation or depression of the articular surface, as well as for preoperative planning.

• Magnetic resonance imaging is useful for evaluating injuries to the menisci, the cruciate and collateral ligaments, and the soft tissue envelope.

• Arteriography should be performed if there is a question of vascular compromise.

CLASSIFICATION

Schatzker (Fig. 30)

• Types I to III are low-energy injuries.

• Types IV to VI are high-energy injuries.

• Type I usually occurs in younger individuals and is associated with medial collateral ligament injuries

• Type III usually occurs in older individuals (Fig. 30)

OTA Classification of Tibial Plateau Fractures

See Fracture and Dislocation Compendium at http://www.ota.org/compendium/index.htm.

TREATMENT

Nonoperative

• Indicated for nondisplaced or minimally displaced fractures and in patients with advanced osteoporosis.

• Protected weight bearing and early range of knee motion in a hinged fracture-brace are recommended.

• Isometric quadriceps exercises and progressive passive, active-assisted, and active range-of-knee motion exercises are indicated.

• Partial weight bearing (30 to 50 lb) for 8 to 12 weeks is allowed, with progression to full weight bearing.

Operative

• Surgical indications:
• The reported range of articular depression that can be accepted varies from <2 mm to 1 cm.

• Instability >10 degrees of the nearly extended knee compared to the contralateral side is an accepted surgical indication. Split fractures are more likely to be unstable than pure depression fractures in which the rim is intact.

Figure 30. Schatzker classification. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

• Open fractures should be treated surgically.

• Compartment syndrome is a surgical indication.

• Associated vascular injury is an indication.

• Operative treatment principles
• Reconstruction of the articular surface, followed by reestablishment of tibial alignment, is the goal.

• Treatment involves buttressing of elevated articular segments with bone graft or bone graft substitute.

• Fracture fixation can involve use of plates and screws, screws alone, or external fixation.

• The choice of implant is related to the fracture patterns, the degree of displacement, and familiarity of the surgeon with the procedure.

• Adequate soft tissue reconstruction including preservation and/or repair of the meniscus as well as intraarticular and extraarticular ligamentous structures should be addressed.

• Spanning external fixation across the knee can be used as a temporizing measure in patients with higher-energy injuries. The external fixator is used to keep the soft tissues out to length and provides some degree of fracture reduction before definitive surgery.

• Arthroscopy may be used to evaluate the articular surfaces, the menisci, and the cruciate ligaments. It may also be used for evacuation of hemarthrosis and particulate debris, for meniscal procedures, and for arthroscopic-assisted reduction and fixation. Its role in the evaluation of rim disorders and its utility in the management of complicated fractures are limited.

• An avulsed anterior cruciate ligament with a large bony fragment should be repaired. If the fragment is minimal or the ligament has an intrasubstance tear, reconstruction should be delayed.

• Surgery in isolated injuries should proceed after a full appreciation of the personality of the fracture. This delay will also allow swelling to subside and local skin conditions to improve.

• Schatzker type I to IV fractures can be fixed with percutaneous screws or lateral placed periarticular plate. If satisfactory closed reduction (<1-mm articular step-off) cannot be achieved with closed techniques, open reduction and internal fixation are indicated.

• The menisci should never be excised to facilitate exposure.

• Depressed fragments can be elevated from below en masse by using a bone tamp working through the split component or a cortical window. The metaphyseal defect should be filled with cancellous autograft, allograft, or a synthetic substitute.

• Type V and VI fractures can be managed using plate and screws, a ring fixator, or a hybrid fixator. Limited internal fixation can be added to restore the articular surface.

• Percutaneous inserted plating, which is a more biologic approach, has been described. In this technique, the plate is slid subcutaneously without soft tissue stripping.

• Use of locked plates has eliminated the need for double plating bicondylar tibial plateau fractures.

• Fractures of the posterior medial plateau may require a posteromedial incision for fracture reduction and plate stabilization.

• Postoperative non–weight bearing with continuous passive motion and active range of motion is encouraged.

• Weight bearing is allowed at 8 to 12 weeks.

COMPLICATIONS

• Knee stiffness: This is common, related to trauma from injury and surgical dissection, extensor retinacular injury, scarring, and postoperative immobility.

• Infection: This is often related to ill-timed incisions through compromised soft tissues with extensive dissection for implant placement.

• Compartment syndrome: This uncommon but devastating complication involves the tight fascial compartments of the leg. It emphasizes the need for high clinical suspicion, serial neurovascular examinations, particularly in the unconscious or obtunded patient, aggressive evaluation, including compartment pressure measuring if necessary, and expedient treatment consisting of emergency fasciotomies of all compartments of the leg.

• Malunion or nonunion: This is most common in Schatzker VI fractures at the metaphyseal-diaphyseal junction, related to comminution, unstable fixation, implant failure, or infection.

• Posttraumatic osteoarthritis: This may result from residual articular incongruity, chondral damage at the time of injury, or malalignment of the mechanical axis.

• Peroneal nerve injury: This is most common with trauma to the lateral aspect of the leg where the peroneal nerve courses in proximity to the fibular head and lateral tibial plateau.

• Popliteal artery laceration.
• Avascular necrosis of small articular fragments: This may result in loose bodies within the knee.

Tibia Fibula Shaft

EPIDEMIOLOGY

• Fractures of the tibia and fibula shaft are the most common long bone fractures.

• In an average population, there are about 26 tibial diaphyseal fractures per 100,000 population per year.

• Men are more commonly affected than women, with the male incidence being about 41 per 100,000 per year and the female incidence about 12 per 100,000 per year.

• The average age of a patient sustaining a tibia shaft fracture is 37 years, with men having an average age of 31 years and women 54 years.

ANATOMY

• The tibia is a long tubular bone with a triangular cross section. It has a subcutaneous anteromedial border and is bounded by four tight fascial compartments (anterior, lateral, posterior, and deep posterior) (Figs. 31 and 32).

• Blood supply
• The nutrient artery arises from the posterior tibial artery, entering the posterolateral cortex distal to the origination of the soleus muscle. Once the vessel enters the intramedullary (IM) canal, it gives off three ascending branches and one descending branch. These give rise to the endosteal vascular tree, which anastomose with periosteal vessels arising from the anterior tibial artery.

• The anterior tibial artery is particularly vulnerable to injury as it passes through a hiatus in the interosseus membrane.

• The peroneal artery has an anterior communicating branch to the dorsalis pedis artery. It may therefore be occluded despite an intact dorsalis pedis pulse.

• The distal third is supplied by periosteal anastomoses around the ankle with branches entering the tibia through ligamentous attachments.

• There may be a watershed area at the junction of the middle and distal thirds (controversial).

• If the nutrient artery is disrupted, there is reversal of flow through the cortex, and the periosteal blood supply becomes more important. This emphasizes the importance of preserving periosteal attachments during fixation.

• The fibula is responsible for 6% to 17% of a weight-bearing load.

• The common peroneal nerve courses around the neck of the fibula, which is nearly subcutaneous in this region; it is therefore especially vulnerable to direct blows or traction injuries at this level.

MECHANISM OF INJURY

• Direct
• High-energy: motor vehicle accident
• Transverse, comminuted, displaced fractures commonly occur.

Figure 31. The anatomy of the tibial and fibular shaft. (From Rockwood CA Jr, Green DP, Bucholz RW, Heckman JD, eds. Rockwood and Green’s Fractures in Adults, 4th ed, vol. 2. Philadelphia: Lippincott-Raven, 1996:2124.)

• The incidence of soft tissue injury is high.

• Penetrating: gunshot
• The injury pattern is variable.

• Low-velocity missiles (handguns) do not pose the problems from bone or soft tissue damage that high-energy (motor vehicle accident) or high-velocity (shotguns, assault weapons) mechanisms cause.

• Bending: three- or four-point (ski boot injuries)

• Short oblique or transverse fractures occur, with a possible butterfly fragment.

• Crush injury occurs.

Figure 32. The four compartments of the leg. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

• Highly comminuted or segmental patterns are associated with extensive soft tissue compromise.

• Must rule out compartment syndrome and open fractures.

• Fibula shaft fractures: These typically result from direct trauma to the lateral aspect of the leg.

• Indirect
• Torsional mechanisms
• Twisting with the foot fixed and falls from low heights are causes.

• These spiral, nondisplaced fractures have minimal comminution associated with little soft tissue damage.

• Stress fractures
• In military recruits, these injuries most commonly occur at the metaphyseal/diaphyseal junction, with sclerosis being most marked at the posteromedial cortex.

• In ballet dancers, these fractures most commonly occur in the middle third; they are insidious in onset and are overuse injuries.

• Radiographic findings may be delayed several weeks.

CLINICAL EVALUATION

• Evaluate neurovascular status. Dorsalis pedis and posterior tibial artery pulses must be evaluated and documented, especially in open fractures in which vascular flaps may be necessary. Common peroneal and tibial nerve integrity must be documented.
• Assess soft tissue injury. Fracture blisters may contraindicate early open reduction.

• Monitor for compartment syndrome. Pain out of proportion to the injury is the most reliable sign of compartment syndrome. Compartment pressure measurements that have been used as an indication for four-compartment fasciotomy have been (1) pressures higher than 30 mm Hg and (2) pressure within 30 mm Hg of diastolic pressure. Deep posterior compartment pressures may be elevated in the presence of a soft superficial posterior compartment.

• Tibial fractures are associated with a high incidence of knee ligament injuries.

• About 5% of all tibial fractures are bifocal, with two separate fractures of the tibia.

RADIOGRAPHIC EVALUATION

• Radiographic evaluation must include the entire tibia (anteroposterior [AP] and lateral views) with visualization of the ankle and knee joints.

• Oblique views may be helpful to further characterize the fracture pattern.

• Postreduction radiographs should include the knee and ankle for alignment and preoperative planning.

• A surgeon should look for the following features on the AP and lateral radiographs:

• The location and morphology of the fracture should be determined.

• The presence of secondary fracture lines: These may displace during operative treatment.

• The presence of comminution: This signifies a higher-energy injury.

• The distance that bone fragments have traveled from their normal location: Widely displaced fragments suggest that the soft tissue attachments have been damaged and the fragments may be avascular.

• Osseous defects: These may suggest missing bone.

• Fracture lines may extend proximally to the knee or distally to the ankle.

• The state of the bone: Is there evidence of osteopenia, metastases, or a previous fracture?

• Osteoarthritis or the presence of a knee arthroplasty: Either may change the treatment method selected by the surgeon.

• Gas in the tissues: These are usually secondary to open fracture but may also signify the presence of gas gangrene, necrotizing fasciitis, or other anaerobic infections.

• Computed tomography and magnetic resonance imaging (MRI) usually are not necessary.

• Technetium bone scanning and MRI scanning may be useful in diagnosing stress fractures before these injuries become obvious on plain radiographs.

• Angiography is indicated if an arterial injury is suspected.

CLASSIFICATION

Poor sensitivity, reproducibility, and interobserver reliability have been reported for most classification schemes.

 

Descriptive

• Open versus closed
• Anatomic location: proximal, middle, or distal third

• Fragment number and position: comminution, butterfly fragments

• Configuration: transverse, spiral, oblique
• Angulation: varus/valgus, anterior/posterior
• Shortening
• Displacement: percentage of cortical contact
• Rotation
• Associated injuries

OTA Classification of Tibial Fractures

See Fracture and Dislocation Compendium at http://www.ota.org/compendium/index.htm.

Gustilo and Anderson Classification of Open Fractures

Grade I:	Clean skin opening of <1 cm, usually from inside to outside; minimal muscle contusion; simple transverse or short oblique fractures
Grade II:	Laceration >1 cm long, with extensive soft tissue damage; minimal to moderate crushing component; simple transverse or short oblique fractures with minimal comminution
Grade III:	Extensive soft tissue damage, including muscles, skin, and neurovascular structures; often a high-energy injury with a severe crushing component
IIIA:	Extensive soft tissue laceration, adequate bone coverage; segmental fractures, gunshot injuries, minimal periosteal stripping
IIIB:	Extensive soft tissue injury with periosteal stripping and bone exposure requiring soft tissue flap closure; usually associated with massive contamination
IIIC:	Vascular injury requiring repair

Tscherne Classification of Closed Fractures

• This classifies soft tissue injury in closed fractures and takes into account indirect versus direct injury mechanisms (Fig. 33).

Grade 0:	Injury from indirect forces with negligible soft tissue damage
Grade I:	Closed fracture caused by low-moderate energy mechanisms, with superficial abrasions or contusions of soft tissues overlying the fracture
Grade II:	Closed fracture with significant muscle contusion, with possible deep, contaminated skin abrasions associated with moderate to severe energy mechanisms and skeletal injury; high risk for compartment syndrome
Grade III:	Extensive crushing of soft tissues, with subcutaneous degloving or avulsion, with arterial disruption or established compartment syndrome

P.393

Figure 33. The Tscherne classification of closed fractures: C0, simple fracture configuration with little or no soft tissue injury; C1, superficial abrasion, mild to moderately severe fracture configuration; C2, deep contamination with local skin or muscle contusion, moderately severe fracture configuration; C3, extensive contusion or crushing of skin or destruction of muscle, severe fracture. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

 

TREATMENT

Nonoperative

Fracture reduction followed by application of a long leg cast with progressive weight bearing can be used for isolated, closed, low-energy fractures with minimal displacement and comminution.

• Cast with the knee in 0 to 5 degrees of flexion to allow for weight bearing with crutches as soon as tolerated by patient, with advancement to full weight bearing by the second to fourth week.

• After 4 to 6 weeks, the long leg cast may be exchanged for a patella-bearing cast or fracture brace.

• Union rates as high as 97% are reported, although with delayed weight bearing related to delayed union or nonunion.

Acceptable Fracture Reduction

• Less than 5 degrees of varus/valgus angulation is recommended.

• Less than 10 degrees of anterior/posterior angulation is recommended (<5 degrees preferred).

• Less than 10 degrees of rotational deformity is recommended, with external rotation better tolerated than internal rotation.

• Less than 1 cm of shortening; 5 mm of distraction may delay healing 8 to 12 months.

• More than 50% cortical contact is recommended.

• Roughly, the anterior superior iliac spine, center of the patella, and base of the second proximal phalanx should be colinear.

Time to Union

• The average time is 16В±4 weeks: This is highly variable, depending on fracture pattern and soft tissue injury.

• Delayed union is defined as >20 weeks.

• Nonunion: This occurs when clinical and radiographic signs demonstrate that the potential for union is lost, including sclerotic ends at the fracture site and a persistent gap unchanged for several weeks. Nonunion has also been defined as lack of healing 9 months after fracture.

Tibia Stress Fracture

• Treatment consists of cessation of the offending activity.

• A short leg cast may be necessary, with partial-weight-bearing ambulation.

Fibula Shaft Fracture

• Treatment consists of weight bearing as tolerated.

• Although not required for healing, a short period of immobilization may be used to minimize pain.

• Nonunion is uncommon because of the extensive muscular attachments.

Operative Treatment

Intramedullary (IM) Nailing

• IM nailing carries the advantages of preservation of periosteal blood supply and limited soft tissue damage. In addition, it carries the biomechanical advantages of being able to control alignment, translation, and rotation. It is therefore recommended for most fracture patterns.
• Locked versus unlocked nail
• Locked nail: This provides rotational control; it is effective in preventing shortening in comminuted fractures and those with significant bone loss. Interlocking screws can be removed at a later time to dynamize the fracture site, if needed, for healing.

• Nonlocked nail: This allows impaction at the fracture site with weight bearing, but it is difficult to control rotation. Nonlocked nails are rarely used.
• Reamed versus unreamed nail
• Reamed nail: This is indicated for most closed and open fractures. It allows excellent IM splinting of the fracture and use of a larger-diameter, stronger nail.

• Unreamed nail: This is designed to preserve the IM blood supply in open fractures where the periosteal supply has been destroyed. It is currently reserved for higher-grade open fractures; its disadvantage is that it is significantly weaker than the larger reamed nail and has a higher risk of implant fatigue failure.

Flexible Nails (Enders, Rush Rods)

• Multiple curved IM pins exert a spring force to resist angulation and rotation, with minimal damage to the medullary circulation.

• These are rarely used in the United States because of the predominance of unstable fracture patterns and success with interlocking nails.

• They are recommended only in children or adolescents with open physes.

External Fixation

• Primarily used to treat severe open fractures, it can also be indicated in closed fractures complicated by compartment syndrome, concomitant head injury, or burns.

• Its popularity in the United States has waned with the increased use of reamed nails for most open fractures.

• Union rates: Up to 90%, with an average of 3.6 months to union.

• The incidence of pin tract infections is 10% to 15%.

Plates and Screws

• These are generally reserved for fractures extending into the metaphysis or epiphysis.

• Reported success rates as high as 97%.

• Complication rates of infection, wound breakdown, and malunion or nonunion increase with higher-energy injury patterns.

Proximal Tibia Fractures

• These account for about 7% of all tibia diaphyseal fractures.

• These fractures are notoriously difficult to nail, because they frequently become malaligned, the commonest deformities being valgus and apex anterior angulation.

• Nailing requires use of special techniques such as blocking screws.

• Use of a percutaneously inserted plate has had recent popularity.

Distal Tibia Fractures

• The risk for malalignment also exists with the use of an IM nail.

• With IM nailing, fibula plating or use of blocking screws may help to prevent malalignment.

• Use of a percutaneously inserted plate has had recent popularity.

Tibia Fracture with an Intact Fibula

• If the tibia fracture is nondisplaced, treatment consists of long leg casting with early weight bearing. Close observation is indicated to recognize any varus tendency.
• Some authors recommend IM nailing even if tibia fracture is nondisplaced.

• A potential risk of varus malunion exists, particularly in patients >20 years.

Fasciotomy

• Evidence of compartment syndrome is an indication for emergent fasciotomy of all four muscle compartments of the leg (anterior, lateral, superficial, and deep posterior) through one or multiple incision techniques. Following operative fracture fixation, the fascial openings should not be reapproximated.

COMPLICATIONS

• Malunion: This includes any deformity outside the acceptable range.

• Nonunion: This associated with high-velocity injuries, open fractures (especially Gustilo grade III), infection, intact fibula, inadequate fixation, and initial fracture displacement.

• Infection may occur.
• Soft tissue loss: Delaying wound coverage for greater than 7 to 10 days in open fractures has been associated with higher rates of infection. Local rotational flaps or free flaps may be needed for adequate coverage.

• Stiffness at the knee and/or ankle may occur.

• Knee pain: This is the most common complication associated with IM tibial nailing.

• Hardware breakage: Nail and locking screw breakage rates depend on the size of the nail used and the type of metal from which it is made. Larger reamed nails have larger cross screws; the incidence of nail and screw breakage is greater with unreamed nails that utilize smaller-diameter locking screws.

• Thermal necrosis of the tibial diaphysis following reaming is an unusual, but serious, complication. Risk is increased with use of dull reamers and reaming under tourniquet control.

• Reflex sympathetic dystrophy: This is most common in patients unable to bear weight early and with prolonged cast immobilization. It is characterized by initial pain and swelling followed by atrophy of limb. Radiographic signs are spotty demineralization of foot and distal tibia and equinovarus ankle. It is treated by elastic compression stockings, weight bearing, sympathetic blocks, and foot orthoses, accompanied by aggressive physical therapy.

• Compartment syndrome: Involvement of the anterior compartment is most common. Highest pressures occur at the time of open or closed reduction. It may require fasciotomy. Muscle death occurs after 6 to 8 hours. Deep posterior compartment syndrome may be missed because of uninvolved overlying superficial compartment, and results in claw toes.

• Neurovascular injury: Vascular compromise is uncommon except with high-velocity, markedly displaced, often open fractures. It most commonly occurs as the anterior tibial artery traverses the interosseous membrane of the proximal leg. It may require saphenous vein interposition graft. The common peroneal nerve is vulnerable to direct injuries to the proximal fibula as well as fractures with significant varus angulation. Overzealous traction can result in distraction injuries to the nerve, and inadequate cast molding/padding may result ieurapraxia.

• Fat embolism may occur.
• Claw toe deformity: This is associated with scarring of extensor tendons or ischemia of posterior compartment muscles.

Ankle Fractures

EPIDEMIOLOGY

• Population-based studies suggest that the incidence of ankle fractures has increased dramatically since the early 1960s.

• The highest incidence of ankle fractures occurs in elderly women.

• Most ankle fractures are isolated malleolar fractures, accounting for two-thirds of fractures, with bimalleolar fractures occurring in one-fourth of patients and trimalleolar fractures occurring in the remaining 5% to 10%.

• Open fractures are rare, accounting for just 2% of all ankle fractures.

• Increased body mass index is considered a risk factor for sustaining an ankle fracture.

ANATOMY

• The ankle is a complex hinge joint composed of articulations among the fibula, tibia, and talus in close association with a complex ligamentous system (Fig. 34).

• The distal tibial articular surface is referred to as the plafond, which, together with the medial and lateral malleoli, forms the mortise, a constrained articulation with the talar dome.

• The plafond is concave in the anteroposterior (AP) plane but convex in the lateral plane. It is wider anteriorly to allow for congruency with the wedge-shaped talus. This provides for intrinsic stability, especially in weight bearing.
• The talar dome is trapezoidal, with the anterior aspect 2.5 mm wider than the posterior talus. The body of the talus is almost entirely covered by articular cartilage.

• The medial malleolus articulates with the medial facet of the talus and divides into an anterior colliculus and a posterior colliculus, which serve as attachments for the superficial and deep deltoid ligaments, respectively.

• The lateral malleolus represents the distal aspect of the fibula and provides lateral support to the ankle. No articular surface exists between the distal tibia and fibula, although there is some motion between the two. Some intrinsic stability is provided between the distal tibia and fibula just proximal to the ankle where the fibula sits between a broad anterior tubercle and a smaller posterior tubercle of the tibia. The distal fibula has articular cartilage on its medial aspect extending from the level of the plafond distally to a point halfway down its remaining length.

• The syndesmotic ligament complex exists between the distal tibia and fibula, resisting axial, rotational, and translational forces to maintain the structural integrity of the mortise. It is composed of four ligaments, including:
• Anterior inferior tibiofibular ligament.
• Posterior inferior tibiofibular ligament. This is thicker and stronger than the anterior counterpart. Therefore, torsional or translational forces that rupture the anterior tibiofibular ligament may cause an avulsion fracture of the posterior tibial tubercle, leaving the posterior tibiofibular ligament intact.

Figure 34. Bony anatomy of the ankle. Mortise view (A), inferior superior view of the tibiofibular side of the joint (B), and superior inferior view of the talus (C). The ankle joint is a three-bone joint with a larger talar articular surface than matching tibiofibular articular surface. The lateral circumference of the talar dome is larger than the medial circumference. The dome is wider anteriorly than posteriorly. The syndesmotic ligaments allow widening of the joint with dorsiflexion of the ankle, into a stable, close-packed position. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

• Transverse tibiofibular ligament (inferior to posterior tibiofibular).

• Interosseous ligament (distal continuation of the interosseous membrane) (Fig. 35).

• The deltoid ligament provides ligamentous support to the medial aspect of the ankle. It is separated into superficial and deep components (Fig. 36):
• Superficial portion: This is composed of three ligaments that originate on the anterior colliculus but add little to ankle stability.

Figure 35. Three views of the tibiofibular syndesmotic ligaments. Anteriorly, the anterior inferior tibiofibular ligament (AITFL) spans from the anterior tubercle and anterolateral surface of the tibia to the anterior fibula. Posteriorly, the tibiofibular ligament has two components: the superficial posterior inferior tibiofibular ligament (PITFL), which is attached from the fibula across to the posterior tibia, and the thick, strong inferior transverse ligament (ITL), which constitutes the posterior labrum of the ankle. Between the anterior and posterior inferior talofibular ligaments resides the stout interosseous ligament (IOL). (Adapted from Browner B, Jupiter J, Levine A, eds. Skeletal Trauma: Fractures, Dislocations, and Ligamentous Injuries, 2nd ed. Philadelphia: WB Saunders, 1997.)

• Tibionavicular ligament: This suspends the spring ligament and prevents inward displacement of the talar head.

• Tibiocalcaneal ligament: This prevents valgus displacement.

• Superficial tibiotalar ligament.
• Deep portion: This intraarticular ligament (deep tibiotalar) originates on the intercollicular grove and the posterior colliculus of the distal tibia and inserts on the entire nonarticular medial surface of the talus. Its fibers are transversely oriented; it is the primary medial stabilizer against lateral displacement of the talus.

• The fibular collateral ligament is made up of three ligaments that, together with the distal fibula, provide lateral support to the ankle. The lateral ligamentous complex is not as strong as the medial complex (Fig. 37).

Figure 36. Medial collateral ligaments of the ankle. Sagittal plane (A) and transverse plane (B) views. The deltoid ligament includes a superficial component and a deep component. Superficial fibers mostly arise from the anterior colliculus and attach broadly from the navicular across the talus and into the medial border of the sustentaculum tali and the posterior medial talar tubercle. The deep layer of the deltoid ligament originates from the anterior and posterior colliculi and inserts on the medial surface of the talus. (Adapted from Browner B, Jupiter J, Levine A, eds. Skeletal Trauma: Fractures, Dislocations, and Ligamentous Injuries, 2nd ed. Philadelphia: WB Saunders, 1997.)

• Anterior talofibular ligament: This is the weakest of the lateral ligaments; it prevents anterior subluxation of the talus primarily in plantar flexion.

• Posterior talofibular ligament: This is the strongest of the lateral ligaments; it prevents posterior and rotatory subluxation of the talus.

Figure 37. Lateral collateral ligaments of the ankle and the anterior syndesmotic ligament. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

• Calcaneofibular ligament: This is lax ieutral dorsiflexion owing to relative valgus orientation of calcaneus; it stabilizes the subtalar joint and limits inversion; rupture of this ligament will cause a positive talar tilt test.

• Biomechanics
• The normal range of motion (ROM) of the ankle in dorsiflexion is 30 degrees, and in plantar flexion it is 45 degrees; motion analysis studies reveal that a minimum of 10 degrees of dorsiflexion and 20 degrees of plantar flexion are required for normal gait.

• The axis of flexion of the ankle runs between the distal aspect of the two malleoli, which is externally rotated 20 degrees compared with the knee axis.

• A lateral talar shift of 1 mm will decrease surface contact by 40%; a 3-mm shift results in >60% decrease.

• Disruption of the syndesmotic ligaments may result in decreased tibiofibular overlap. Syndesmotic disruption associated with fibula fracture may be associated with a 2- to 3-mm lateral talar shift even with an intact deep deltoid ligament. Further lateral talar shift implies medial compromise.

MECHANISM OF INJURY

The pattern of ankle injury depends on many factors, including mechanism (axial versus rotational loading), chronicity (recurrent ankle instability may result in chronic ligamentous laxity and distorted ankle biomechanics), patient age, bone quality, position of the foot at time of injury, and the magnitude, direction, and rate of loading. Specific mechanisms and injuries are discussed in the section on classification.

CLINICAL EVALUATION

• Patients may have a variable presentation, ranging from a limp to nonambulatory in significant pain and discomfort, with swelling, tenderness, and variable deformity.

• Neurovascular status should be carefully documented and compared with the contralateral side.

• The extent of soft tissue injury should be evaluated, with particular attention to possible open injuries and blistering. The quality of surrounding tissues should also be noted.
• The entire length of the fibula should be palpated for tenderness, because associated fibular fractures may be found proximally as high as the proximal tibiofibular articulation. A squeeze tests may be performed approximately 5 cm proximal to the intermalleolar axis to assess possible syndesmotic injury.

• A dislocated ankle should be reduced and splinted immediately (before radiographs if clinically evident) to prevent pressure or impaction injuries to the talar dome and to preserve neurovascular integrity.

RADIOGRAPHIC EVALUATION

• AP, lateral, and mortise views of the ankle should be obtained.

• AP view
• Tibiofibula overlap of <10 mm is abnormal and implies syndesmotic injury.

• Tibiofibula clear space of >5 mm is abnormal and implies syndesmotic injury.

• Talar tilt: A difference in width of the medial and lateral aspects of the superior joint space of >2 mm is abnormal and indicates medial or lateral disruption.

• Lateral view
• The dome of the talus should be centered under the tibia and congruous with the tibial plafond.

• Posterior tibial tuberosity fractures can be identified, as well as direction of fibular injury.

• Avulsion fractures of the talus by the anterior capsule may be identified.

• Mortise view (Fig. 38)
• This is taken with the foot in 15 to 20 degrees of internal rotation to offset the intermalleolar axis.

• A medial clear space >4 to 5 mm is abnormal and indicates lateral talar shift.

• Talocrural angle: The angle subtended between the intermalleolar line and a line parallel to the distal tibial articular surface should be between 8 and 15 degrees. The angle should be within 2 to 3 degrees of the uninjured ankle.

• Tibiofibular overlap <1 cm indicates syndesmotic disruption.

• Talar shift >1 mm is abnormal.

• A physician-assisted stress view with the ankle dorsiflexed and the foot stressed in external rotation can be used to identify medial injury with an isolated fibula fracture.

• Computed tomography (CT) scans help to delineate bony anatomy, especially in patients with plafond injuries.

• Magnetic resonance imaging (MRI) may be used for assessing occult cartilaginous, ligamentous, or tendinous injuries.

• Bone scan is useful in chronic ankle injuries, such as osteochondral injuries, stress fractures, infection, or reflex dystrophies.

CLASSIFICATION

Lauge-Hansen (Figs. 39 and 40)

• Four patterns are recognized, based on “pure” injury sequences, each subdivided into stages of increasing severity.

• This system is based on cadaveric studies.

• Patterns may not always reflect clinical reality.

• The system takes into account (1) the position of the foot at the time of injury and (2) the direction of the deforming force.

Supination-Adduction (SA)

• This accounts for 10% to 20% of malleolar fractures.

• This is the only type associated with medial displacement of the talus.

Stage I:	Produces either a transverse avulsion-type fracture of the fibula distal to the level of the joint or a rupture of the lateral collateral ligaments
Stage II:	Results in a vertical medial malleolus fracture

Supination-External Rotation (SER)

• This accounts for 40% to 75% of malleolar fractures.

Stage I:	Produces disruption of the anterior tibiofibular ligament with or without an associated avulsion fracture at its tibial or fibular attachment
Stage II:	Results in the typical spiral fracture of the distal fibula, which runs from anteroinferior to posterosuperior
Stage III:	Produces either a disruption of the posterior tibiofibular ligament or a fracture of the posterior malleolus
Stage IV:	Produces either a transverse avulsion-type fracture of the medial malleolus or a rupture of the deltoid ligament

 

Figure 38. X-ray appearance of the normal ankle on mortise view. (A) The condensed subchondral bone should form a continuous line around the talus. (B) The talocrural angle should be approximately 83 degrees. When the opposite side can be used as a control, the talocrural angle of the injured side should be within a few degrees of the noninjured side. (C) The medial clear space should be equal to the superior clear space between the talus and the distal tibia and less than or equal to 4 mm on standard x-rays. (D) The distance between the medial wall of the fibula and the incisural surface of the tibia, the tibiofibular clear space, should be less than 6 mm. (A–C, Adapted from Browner B, Jupiter J, Levine A, eds. Skeletal Trauma: Fractures, Dislocations, and Ligamentous Injuries, 2nd ed. Philadelphia: WB Saunders, 1997; D, from Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

Figure 39. Schematic diagram and case examples of Lauge-Hansen supination-external rotation and supination-adduction ankle fractures. A supinated foot sustains either an external rotation or adduction force and creates the successive stages of injury shown in the diagram. The supination-external rotation mechanism has four stages of injury, and the supination-adduction mechanism has two stages. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

 

Figure 40. Schematic diagram and case examples of Lauge-Hansen pronation-external rotation and pronation-abduction ankle fractures. A pronated foot sustains either an external rotation or abduction force and creates the successive stages of injury shown in the diagram. The pronation-external rotation mechanism has four stages of injury, and the pronation-abduction mechanism has three stages. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

Pronation-Abduction (PA)

• This accounts for 5% to 20% of malleolar fractures.

Stage I:	Results in either a transverse fracture of the medial malleolus or a rupture of the deltoid ligament
Stage II:	Produces either a rupture of the syndesmotic ligaments or an avulsion fracture at their insertion sites
Stage III:	Produces a transverse or short oblique fracture of the distal fibula at or above the level of the syndesmosis; this results from a bending force that causes medial tension and lateral compression of the fibula, producing lateral comminution or a butterfly fragment

Pronation-External Rotation (PER)

• This accounts for 5% to 20% of malleolus fractures.

Danis-Weber (Fig. 41)

• This is based on the level of the fibular fracture: the more proximal, the greater the risk of syndesmotic disruption and associated instability. Three types of fractures are described:

 

Figure 41. (A) Schematic diagram of the Danis-Weber classification of ankle fractures. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

OTA Classification of Ankle Fractures

See Fracture and Dislocation Compendium at http://www.ota.org/compendium/index.htm.

Fracture Variants

• Maisonneuve fracture
• Originally described as an ankle injury with a fracture of the proximal third of the fibula, this is an external rotation-type injury; it is important to distinguish it from direct trauma fractures.

• Curbstone fracture
• This avulsion fracture off the posterior tibia is produced by a tripping mechanism.

• LeForte-Wagstaffe fracture
• This anterior fibular tubercle avulsion fracture by the anterior tibiofibular ligament is usually associated with Lauge-Hansen SER-type fracture patterns.

• Tillaux-Chaput fracture
• This avulsion of anterior tibial margin by the anterior tibiofibular ligament is the tibial counterpart of the LeForte-Wagstaffe fracture.

• Collicular fractures
• Anterior colliculus fracture: The deep portion of the deltoid may remain intact.

• Posterior colliculus fracture: The fragment is usually nondisplaced because of stabilization by the posterior tibial and the flexor digitorum longus tendons; classically, one sees a supramalleolar spikes very clearly on an external rotation view.

• Chip avulsion
• Small avulsions of either colliculus can be noted.

• Pronation-dorsiflexion fracture
• This displaced fracture off the anterior articular surface is considered a pilon variant when there is a significant articular fragment.

TREATMENT

The goal of treatment is anatomic restoration of the ankle joint. Fibular length and rotation must be restored.

Emergency Room

• Closed reduction should be performed for displaced fractures. Fracture reduction helps to minimize postinjury swelling, reduces pressure on the articular cartilage, lessens the risk of skin breakdown, and minimizes pressure on the neurovascular structures.

• Dislocated ankles should be reduced before radiographic evaluation.

• Open wounds and abrasions should be cleansed and dressed in a sterile fashion as dictated by the degree of injury. Fracture blisters should be left intact and dressed with a well-padded sterile dressing.

• Following fracture reduction, a well-padded posterior splint with a U-shaped component should be placed to provide fracture stability and patient comfort.

• Postreduction radiographs should be obtained for fracture reassessment. The limb should be aggressively elevated with or without the use of ice.

Nonoperative

• Indications for nonoperative treatment include:

• Nondisplaced, stable fracture patterns with an intact syndesmosis.

• Displaced fractures for which stable anatomic reduction is achieved.

• An unstable or multiple trauma patient in whom operative treatment is contraindicated because of the condition of the patient or the limb.

• Patients with stable fracture patterns can be placed in a short leg cast or a removable boot or stirrup and allowed to bear weight as tolerated.

• For displaced fractures, if anatomic reduction is achieved with closed manipulation, a bulky dressing and a posterior splint with a U-shaped component may be used for the first few days while swelling subsides. The patient is then placed in a long leg cast to maintain rotational control for 4 to 6 weeks with serial radiographic evaluation to ensure maintenance of reduction and healing. If adequate healing is demonstrated, the patient can be placed in a short leg cast or fracture brace. Weight bearing is restricted until fracture healing is demonstrated.

Operative

• Open reduction and internal fixation (ORIF) is indicated for:

• Failure to achieve or maintain closed reduction with amenable soft tissues.

• Unstable fractures that may result in talar displacement or widening of the ankle mortise.

• Fractures that require abnormal foot positioning to maintain reduction (e.g., extreme plantar flexion).

• Open fractures.
• ORIF should be performed once the patient’s general medical condition, swelling about the ankle, and soft tissue status allow. Swelling, blisters, and soft tissue issues usually stabilize within 5 to 10 days after injury with elevation, ice, and compressive dressings. Occasionally, a closed fracture with severe soft tissue injury or massive swelling may require reduction and stabilization with use of external fixation to allow soft tissue management before definitive fixation.

• Lateral malleolar fractures distal to the syndesmosis may be stabilized using a lag screw or Kirschner wires with tension banding. With fractures at or above the syndesmosis, restoration of fibular length and rotation is essential to obtain an accurate reduction. This is most often accomplished using a combination of lag screws and plate.

• Management of medial malleolar fractures is controversial. In general, with a deltoid rupture the talus follows the fibula. Indications for operative fixation of the medial malleolus include concomitant syndesmotic injury, persistent widening of the medial clear space following fibula reduction, inability to obtain adequate fibular reduction, or persistent medial fracture displacement after fibular fixation. Medial malleolar fractures can usually be stabilized with cancellous screws or a figure-of-eight tension band.

• Indications for fixation of posterior malleolus fractures include involvement of >25% of the articular surface, >2 mm displacement, or persistent posterior subluxation of the talus. Fixation may be achieved by indirect reduction and placement of an anterior to posterior lag screw, or a posterior to anterior lag screw through a separate incision.

• Fibula fractures above the plafond may require syndesmotic stabilization. After fixation of the medial and lateral malleoli is achieved, the syndesmosis should be stressed intraoperatively by lateral pull on the fibula with a bone hook or by stressing the ankle in external rotation. Syndesmotic instability can then be recognized clinically and under image intensification. Distal tibia-fibula joint reduction is held with a large-pointed reduction clamp A syndesmotic screw is placed 1.5 to 2.0 cm above the plafond from the fibula to the tibia. Controversy exists as to the number of purchased cortices (three or four) and the size of the screw (3.5 or 4.5 mm). The need for ankle dorsiflexion during syndesmotic screw placement is also controversial.

• Very proximal fibula fractures with syndesmosis disruption can usually be treated with syndesmosis fixation without direct fibula reduction and stabilization. One must however, ascertain correct fibula length and rotation before placing syndesmotic fixation.

• Following fracture fixation, the limb is placed in a bulky dressing incorporating a plaster splint. Progression to weight bearing is based on the fracture pattern, stability of fixation, patient compliance, and philosophy of the surgeon.

Open Fractures

• These fractures require emergent irrigation and debridement in the operating room.

• Stable fixation is important prophylaxis against infection and helps soft tissue healing. It is permissible to leave plates and screws exposed, but efforts should be made to cover hardware, if possible.

• Tourniquet use should be avoided.

• Antibiotic prophylaxis should be continued postoperatively.

• Serial debridements may be required for removal of necrotic, infected, or compromised tissues.

COMPLICATIONS

• Nonunion: Rare and usually involve the medial malleolus when treated closed, associated with residual fracture displacement, interposed soft tissue, or associated lateral instability resulting in shear stresses across the deltoid ligament. If symptomatic, it may be treated with ORIF or electrical stimulation. Excision of the fragment may be necessary if it is not amenable to internal fixation and the patient is symptomatic.

• Malunion: The lateral malleolus is usually shortened and malrotated; a widened medial clear space and a large posterior malleolar fragment are most predictive of poor outcome. The medial malleolus may heal in an elongated position resulting in residual instability.

• Wound problems: Skin edge necrosis (3%) may occur; there is decreased risk with minimal swelling, no tourniquet, and good soft tissue technique. Fractures that are operated on in the presence of fracture blisters or abrasions have more than twice the complication rate.

• Infection: Occurs in <2% of closed fractures; leave implants in situ if stable, even with deep infection. One can remove the implant after the fracture unites. The patient may require serial debridements with possible arthrodesis as a salvage procedure.

• Posttraumatic arthritis: Secondary to damage at the time of injury, from altered mechanics, or as a result of inadequate reduction. It is rare in anatomically reduced fractures, with increasing incidence with articular incongruity.

• Reflex sympathetic dystrophy: Rare and may be minimized by anatomic restoration of the ankle and early return to function.

• Compartment syndrome of foot: Rare.

• Tibiofibular synostosis: This is associated with the use of a syndesmotic screw and is usually asymptomatic.

• Loss of reduction: Reported in 25% of unstable ankle injuries treated nonoperatively.

• Loss of ankle ROM may occur.

PLAFOND (PILON) FRACTURES

Epidemiology

• Pilon fractures account for 7% to 10% of all tibia fractures.

• Most pilon fractures are a result of high-energy mechanisms; thus, concomitant injuries are common and should be ruled out.

• Most common in men 30 to 40 years old.

Mechanism of Injury

• Axial compression: fall from a height

• The force is axially directed through the talus into the tibial plafond, causing impaction of the articular surface; it may be associated with significant comminution. If the fibula remains intact, the ankle is forced into varus with impaction of the medial plafond. Plantar flexion or dorsiflexion of the ankle at the time of injury results in primarily posterior or anterior plafond injury, respectively.

• Shear: skiing accident
• Mechanism is primarily torsion combined with a varus or valgus stress. It produces two or more large fragments and minimal articular comminution. There is usually an associated fibula fracture, which is usually transverse or short oblique.

• Combined compression and shear
• These fracture patterns demonstrate components of both compression and shear. The vector of these two forces determines the fracture pattern.

• Because of their high-energy nature, these fractures can be expected to have specific associated injuries: Calcaneus, tibial plateau, pelvis, and vertebral fractures.

Clinical Evaluation

• Most pilon fractures are associated with high-energy trauma; full trauma evaluation and survey may be necessary.

• Patients typically present nonambulatory with variable gross deformity of the involved distal leg.

• Evaluation includes assessment of neurovascular status and evaluation of any associated injuries.

• The tibia is nearly subcutaneous in this region; therefore, fracture displacement or excess skin pressure may convert a closed injury into an open one.

• Swelling is often massive and rapid, necessitating serial neurovascular examinations as well as assessment of skin integrity, necrosis, and fracture blisters.

• Meticulous assessment of soft tissue damage is of paramount importance. Significant damage occurs to the thin soft tissue envelope surrounding the distal tibia as the forces of impact are dissipated. This may result in inadequate healing of surgical incisions with wound necrosis and skin slough if not treated appropriately. Some advise waiting 7 to 10 days for soft tissue healing to occur before planning surgery.

Radiographic Evaluation

• AP, lateral, and mortise radiographs should be obtained.

• CT with coronal and sagittal reconstruction is helpful to evaluate the fracture pattern and articular surface.

• Careful preoperative planning is essential with a strategically planned sequence of reconstruction; radiographs of the contralateral side may be useful as a template for preoperative planning.

Classification

Ruedi and Allgower (Fig. 42)

• Based on the severity of comminution and the displacement of the articular surface.

• It is the most commonly used classification.

• Prognosis correlates with increasing grade.

Type 1:	Nondisplaced cleavage fracture of the ankle joint
Type 2:	Displaced fracture with minimal impaction or comminution
Type 3:	Displaced fracture with significant articular comminution and metaphyseal impaction

Mast

• Combination of the Lauge-Hansen classification of ankle fractures and the Ruedi-Allgower classification.

Type A:	Malleolar fractures with significant posterior lip involvement (Lauge-Hansen SER IV injury)
Type B:	Spiral fractures of the distal tibia with extension into the articular surface
Type C:	Central impaction injuries as a result of talar impaction, either with or without fibula fracture; subtypes 1, 2, and 3 correspond to the Ruedi -Allgower classification

OTA Classification of Distal Tibia Fractures

See Fracture and Dislocation Compendium at http://www.ota.org/compendium/index.htm.

Treatment

This is based on many factors, including patient age and functional status, severity of injury to bone, cartilage, and soft tissue envelope, degree of comminution and osteoporosis, and the capabilities of the surgeon.

Figure 42. Ruedi and Allgower classified distal tibia fractures into three types based on the degree of articular comminution, as illustrated. The majority of the literature on fractures of the distal tibia has used this classification. (Adapted from Muјller M, Allgower M, Schneider R, et al. Manual of Internal Fixation, 2nd ed. New York: Springer-Verlag, 1979.)

Nonoperative

Treatment involves a long leg cast for 6 weeks followed by fracture brace and ROM exercises or early ROM exercises:

• This is used primarily for nondisplaced fracture patterns or severely debilitated patients.

• Manipulation of displaced fractures is unlikely to result in reduction of intraarticular fragments.

• Loss of reduction is common.

• Inability to monitor soft tissue status and swelling is a major disadvantage.

Operative

• Displaced pilon fractures are usually treated surgically.

TIMING OF SURGERY

• Surgery may be delayed for several days (7 to 14 days on average) to allow for optimization of soft tissue status, including a diminution of swelling about the ankle, resolution of fracture blisters, and sloughing of compromised soft tissues.

• High-energy injuries can be treated with spanning external fixation to provide skeletal stabilization, restoration of length and partial fracture reduction while awaiting definitive surgery. Associated fibula fractures may undergo ORIF at the time of fixator application.

GOALS

The goals of operative fixation of pilon fractures include:

• Maintenance of fibula length and stability.

• Restoration tibial articular surface.
• Bone grafting of metaphyseal defects.

• Buttressing of the distal tibia.

SURGICAL TACTIC

• Articular fracture reduction can be achieved percutaneously or through small limited approaches assisted by a variety of reduction forceps, with fluoroscopy to judge fracture reduction.

• The metaphyseal fracture can be stabilized either with plates or with a nonspanning or spanning external fixator.

• Bone grafting of metaphyseal defects is indicated.

• Internal fixation: Open fracture reduction and plate fixation may be the best way to achieve a precisely reduced articular surface. To minimize the complications of plating, the following techniques have been recommended:

• Surgical delay until definitive surgical treatment using initial spanning external fixation for high energy injuries.

• Use of small, low-profile implants.

• Avoidance of incisions over the anteromedial tibia.

• Use of indirect reduction techniques to minimize soft tissue stripping.

• Use of percutaneous techniques for plate insertion.

• Joint spanning external fixation: This may be used in patients with significant soft tissue compromise or open fractures. Reduction is maintained via distraction and ligamentotaxis. If adequate reduction is obtained, external fixation may be used as definitive treatment.

• Articulating versus nonarticulating spanning external fixation: Nonarticulating (rigid) external fixation are most commonly used, theoretically allowing no ankle motion. Articulating external fixation allows motion in the sagittal plane, thus preventing ankle varus and shortening; application is limited, but theoretically it results in improved chondral lubrication and nutrition owing to ankle motion, and it may be used when soft tissue integrity is the primary indication for external fixation.

• Hybrid external fixation: This is a type of nonspanning external fixator. Fracture reduction is enhanced using thin wires with or without olives to restore the articular surface and maintain bony stability. It is especially useful when internal fixation of any kind is contraindicated. There is a reported 3% incidence of deep wound infection.

ARTHRODESIS

Few advocate performing this procedure acutely. It is best done after fracture comminution has consolidated and soft tissues have recovered. It is generally performed as a salvage procedure after other treatments have failed and posttraumatic arthritis has ensued.

POSTOPERATIVE MANAGEMENT

• Initial splint placement in neutral dorsiflexion with careful monitoring of soft tissues.

• Early ankle and foot motion when wounds and fixation allow.

• Non–weight bearing for 12 to 16 weeks, then progression to full weight bearing once there is radiographic evidence of healing.

Complications

• Even when accurate reduction is obtained, predictably excellent outcomes are not always achieved, and less than anatomic reduction can lead to satisfactory outcomes.

• Soft tissue slough, necrosis, and hematoma: These result from initial trauma combined with improper handling of soft tissues. One must avoid excessive stripping and skin closure under tension. Secondary closure, skin grafts, or muscle flaps may be required for adequate closure.

• Nonunion: Results from significant comminution and bone loss, as well as hypovascularity and infection. It has a reported incidence of 5% regardless of treatment method.

• Malunion: Common with nonanatomic reduction, inadequate buttressing followed by collapse, or premature weight bearing. The reported incidence is up to 25% with use of external fixation.

• Infection: Associated with open injuries and soft tissue devitalization. It has a high incidence with early surgery under unfavorable soft tissue conditions. Late infectious complications may manifest as osteomyelitis, malunion, or nonunion.

• Posttraumatic arthritis: More frequent with increasing severity of intraarticular comminution; it emphasizes the need for anatomic restoration of the articular surface.

• Tibial shortening: Caused by fracture comminution, metaphyseal impaction, or initial failure to restore length by fibula fixation.

• Decreased ankle ROM: Patients usually average <10 degrees of dorsiflexion and <30 degrees of plantar flexion.

LATERAL ANKLE LIGAMENT INJURIES

• Sprains of the lateral ligaments of the ankle are the most common musculoskeletal injury in sports.

• In the United States, it is estimated that one ankle inversion injury occurs each day per 10,000 people.

• One year after injury, occasional intermittent pain is present in up to 40% of patients.

Mechanism of Injury

• Most ankle sprains are caused by a twisting or turning event to the ankle. This can result from either internal or external rotation.
• Mechanism of injury and the exact ligaments injured depend on the position of the foot and the direction of the stress.

• With ankle plantar flexion, inversion injuries first strain the anterior talofibular ligament and then the calcaneofibular ligament.

• With the ankle dorsiflexion and inversion, the injury is usually isolated to the calcaneofibular ligament. With ankle dorsiflexion and external rotation, the injury more likely will involve the syndesmotic ligaments. The syndesmotic ligaments, and in particular the posterior and inferior tibiofibular ligament, can also be injured with the ankle dorsiflexed and the foot internally rotated.

Classification

• Mild ankle sprain: Patients have minimal functional loss, no limp, minimal or no swelling, point tenderness, and pain with reproduction of mechanism of injury.

• Moderate sprain: Patients have moderate functional loss, inability to hop or toe-rise on the injured ankle, a limp with walking, and localized swelling with point tenderness.

• Severe sprain: This is indicated by diffuse tenderness, swelling, and a preference for non–weight bearing.

• This system does not delineate the specific ligaments involved.

Clinical Evaluation

• Patients often describe a popping or tearing sensation in the ankle, and they remember the immediate onset of pain.

• Some patients have an acute onset of swelling around the lateral ankle ligaments and difficulty with weight bearing secondary to pain.

• Significant physical examination findings may include swelling, ecchymosis, tenderness, instability, crepitus, sensory changes, vascular status, muscle dysfunction, and deformity.

• The location of the pain helps to delineate the involved ligaments, and it can include the lateral aspect of the ankle, the anterior aspect of the fibula, the medial aspect of the ankle, and the syndesmotic region.

• The value of stress testing of the lateral collateral ankle ligaments in the acute setting is controversial.

• At the time of injury, before swelling and inflammation occur, the physician may be able to obtain valuable information by performing an anterior drawer and varus stress examination of the lateral collateral ankle ligaments.

• In patients who present several hours after injury and who have powerful reflex inhibition, a stress test without anesthesia is unlikely to give valuable clinical information.

• Injury to the lateral collateral ankle ligaments should be differentiated from other periarticular ligamentous injuries on examination. Significant initial ecchymosis along the heel indicates possible subtalar ligamentous sprain. To evaluate potential syndesmotic injury, the squeeze test and stress external rotation tests are performed (see later).

Radiographic Evaluation

• Most patients should probably undergo radiographic examination to rule out occult foot and ankle injuries with an x-ray series of the foot and ankle.

• The injuries that need to be ruled out include fracture of the base of the fifth metatarsal, navicular fracture, fracture of the anterior process of the calcaneus, fracture of the lateral process of the talus, os trigonal fracture, talar dome fracture (osteochondritis dissecans), and posterior malleolar fracture.

• In the acute setting, there probably is little role for performing radiographic stress testing.

Treatment

• Nonsurgical approaches are preferred for initial treatment for acute ankle sprains.

• Initial treatment involves the use of rest, ice, compression (elastic wrap), elevation (RICE) and protected weight bearing.

• For mild sprains, one can start early mobilization, ROM, and isometric exercises.

• For moderate or severe sprains, one can immobilize the ankle ieutral position, or slight dorsiflexion, for the first 10 to 14 days, and then initiate mobilization, ROM, and isometric exercises. Crutches are discontinued once the patient can tolerate full weight on the ankle.

• Once the initial inflammatory phase has resolved, for the less severe ankle sprains (mild to moderate), one can initiate a home rehabilitation program consisting of eversion muscle group strengthening, proprioceptive retraining, and protective bracing while the patient gradually returns to sports and functional activities. Bracing or taping is usually discontinued 3 to 4 weeks after resuming sports. For more severe sprains, taping or bracing programs are continued during sports activities for 6 months, and a supervised rehabilitation program used.

• Patients who continue to have pain in the ankle that does not decrease with time should be reevaluated for an occult osseous or chondral injury.

• Patients with a history of recurrent ankle sprains who sustain an acute ankle sprain are treated in a manner similar to that described earlier.

SYNDESMOSIS SPRAINS

• Syndesmotic sprains account for approximately 1% of all ankle sprains.

• Syndesmotic sprains may occur without a fracture or frank diastasis.

• Many of these injuries probably go undiagnosed and cause chronic ankle pain.

• Injuries to the syndesmotic ligaments are more likely to result in greater impairment than straightforward lateral ankle sprains. In athletes, syndesmotic sprains result in substantially greater lost time from sports activities.

Classification

Diastases of the distal tibiofibular syndesmosis were classified into four types by Edwards and DeLee.

• Type I diastasis involves lateral subluxation without fracture.

• Type II involved lateral subluxation with plastic deformation of the fibula.

• Type III involves posterior subluxation/dislocation of the fibula.

• Type IV involves superior subluxation/dislocation of the talus within the mortise.

Clinical Evaluation

• Immediately after a syndesmotic ankle sprain, the patient will have well-localized tenderness in the area of the sprain, but soon thereafter, with ensuing swelling and ecchymosis, the precise location of the sprain often becomes obscured.

• Patients ordinarily present to physicians several hours, if not days, after these injuries, with difficulty in weight bearing, ecchymosis extending up the leg, and marked swelling. The clue to chronic, subclinical syndesmotic sprains is the history of vague ankle pain with push-off and normal imaging studies.

• The clinical examination involves palpating the involved ligaments and bones. The fibula should be palpated in a proximal to distal direction. The proximal tibiofibular joint should be assessed for tenderness or associated injury.

• Two clinical tests can be used to isolate syndesmotic ligament injury.

• The squeeze test, described by Hopkinson et al., involves squeezing the fibula at the midcalf. If this maneuver reproduces distal tibiofibular pain, it is likely that the patient has sustained some injury to the syndesmotic region.

• The single best physical examination test for a syndesmotic injury is probably the external rotation stress test. The patient is seated, with the knee flexed at 90 degrees. The examiner stabilizes the patients leg and externally rotates the foot. If this reproduces pain at the syndesmosis, the test is positive, and the physician should assume, in the absence of bony injuries, that a syndesmotic injury has occurred.

Radiographic Evaluation

• The radiographic evaluation of a syndesmotic injury, in an acute setting, involves an attempt at weight-bearing radiographs of the ankle (AP, mortise, lateral) and, if negative, an external rotation stress view.

• Without injury, a weight-bearing mortise view should show:

• No widening of the medial clear space between the medial malleolus and the medial border of the talus.

• A tibiofibular clear space (the interval between the medial border of the fibula and the lateral border of the posterior tibial malleolus) of 6 mm or less.

With acute sprains, on lateral radiographs, a small avulsion fragment may be apparent. Similarly, with more chronic problems, calcification of the syndesmosis or posterior tibia may suggest syndesmotic injury.

• When routine x-rays are negative, and the patient is still suspected of having a syndesmotic injury, stress radiographs can be considered. The examiner should inspect stress radiographs for widening of the medial joint space and tibiofibular clear space on the mortise view and for posterior displacement of the fibula relative to the tibia on the lateral view.

• In difficult-to-diagnose acute cases or latent presentations, an MRI evaluation of the syndesmosis may delineate injury to the syndesmotic ligaments.

Treatment

• Tibiofibular syndesmotic ligamentous injuries are slower to recover than other ankle ligamentous injuries and may benefit from a more restrictive approach to initial management.

• Patients are immobilized in a non-weight-bearing cast for 2 to 3 weeks after injury. This is followed by use of a protective, modified, articulated ankle-foot orthosis that eliminates external rotation stress on the ankle for a variable period, depending on the functional needs and sports activities of the patient.

• Operative treatment is considered for patients with irreducible diastasis. To hold the syndesmotic ligaments while healing, two screws usually placed at the superior margin of the syndesmosis in a nonlagged fashion, from the fibula into the tibia. The patients are maintained non-weight bearing for 6 weeks, and the screws are removed approximately 12 to 16 weeks after fixation.

PERONEAL TENDON SUBLUXATION

• Subluxation and dislocation of the peroneal tendons are uncommon and usually result from sports activities.

• They normally result from forced dorsiflexion or inversion and have been described principally in skiers when they dig the tips of the skis into the snow and create a sudden deceleration force with dorsiflexion of the ankle within the ski boot.

• The injury is easily misdiagnosed as an ankle sprain, and it can result in recurrent or chronic dislocation.

• Presentation is similar to that of a lateral ankle sprain with lateral ankle swelling, tenderness, and ecchymosis.

Clinical Evaluation

• Patients with peroneal tendon subluxation or dislocation demonstrate tenderness posterior to the lateral malleolus.

• The anterior drawer test is negative, and the patient has discomfort and apprehension with resisted eversion of the foot.

• Radiographic evaluation of a patient with peroneal tendon subluxation or dislocation may reveal a small fleck of bone off the posterior aspect of the lateral malleolus, which is best seen on the internal oblique or mortise view.

• If the diagnosis is unclear, as a result of swelling and diffuse ecchymosis, an MRI evaluation may help to delineate this soft tissue injury.

Treatment

• When the initial reduction of dislocated tendons is stable, nonoperative techniques can be successful.

• Management consists of immobilization in a well-molded cast with the foot in slight plantar flexion and mild inversion in an attempt to relax the superior peroneal retinaculum and to maintain reduction in the retrofibular space. Non–weight-bearing immobilization is continued for 6 weeks to allow adequate time for retinacular and periosteal healing.

• When the diagnosis is made on a delayed basis or the patient presents with recurrent dislocations, operative treatment is considered because nonoperative measures are unlikely to work.

• Surgical alternatives include transfer of the lateral Achilles tendon sheath, fibular osteotomy to create a deeper groove for the tendons, rerouting of the peroneal tendons under the fibulocalcaneal ligament, or simple reconstructive repair of the superior peroneal retinaculum with relocation of the tendons.

• Postoperatively, the leg is splinted for 1 to 2 weeks in a slightly inverted and plantar flexed position; patients are then started on a passive motion exercise program to reduce scar formation in the peroneal groove and to increase the likelihood of good tendoutrition and retinacular healing. Weight bearing is initiated 6 weeks postoperatively, and rehabilitation and focusing of strength and ROM are initiated soon thereafter.

 

Calcaneus Fractures

EPIDEMIOLOGY

• Calcaneus fractures account for approximately 2% of all fractures.

• The calcaneus, or os calcis, is the most frequently fractured tarsal bone.

• Displaced intraarticular fractures comprise 60% to 75% of calcaneus fractures.

• Ninety percent of calcaneus fractures occur in men between 21 and 45 years of age, with the majority being in industrial workers.

• Between 7% and 15% of calcaneus fractures are open injuries.

ANATOMY

• The anterior half of the superior articular surface contains three facets that articulate with the talus. The posterior facet is the largest and constitutes the major weight-bearing surface. The middle facet is located anteromedially on the sustentaculum tali. The anterior facet is often confluent with the middle facet.

• Between the middle and posterior facets lies the interosseous sulcus (calcaneal groove), which, with the talar sulcus, forms the sinus tarsi.

• The sustentaculum tali supports the neck of the talus medially; it is attached to the talus by the interosseus talocalcaneal and deltoid ligaments and contains the middle articular facet on its superior aspect. The flexor hallucis longus tendon passes beneath the sustentacular tali medially.

• The peroneal tendons pass between the calcaneus and the lateral malleolus laterally.

• The Achilles tendon attaches to the posterior tuberosity.

MECHANISM OF INJURY

• Axial loading: Falls from a height are responsible for most intraarticular fractures; they occur as the talus is driven down into the calcaneus, which is composed of a thin cortical shell surrounding cancellous bone. In motor vehicle accidents, calcaneus fractures may occur when the accelerator or brake pedal impacts the plantar aspect of the foot.

• Twisting forces may be associated with extraarticular calcaneus fractures, in particular fractures of the anterior and medial processes or the sustentaculum. In diabetic patients, there is an increased incidence of tuberosity fractures from avulsion by the Achilles tendon.

CLINICAL EVALUATION

• Patients typically present with moderate to severe heel pain, associated with tenderness, swelling, heel widening, and shortening. Ecchymosis around the heel extending to the arch is highly suggestive of calcaneus fracture. Blistering may be present and results from massive swelling usually within the first 36 hours after injury. Open fractures are rare, but when present they occur medially.

•  Careful evaluation of soft tissues and neurovascular status is essential. Compartment syndrome of the foot must be ruled out, because this occurs in 10% of calcaneus fractures and may result in clawing of the lesser toes.

Associated Injuries

• Up to 50% of patients with calcaneus fractures may have other associated injuries, including lumbar spine fractures (10%) or other fractures of the lower extremities (25%); intuitively, these injuries are more common in higher-energy injuries.

• Bilateral calcaneus fractures are present in 5% to 10% of cases.

RADIOGRAPHIC EVALUATION

• The initial radiographic evaluation of the patient with a suspected calcaneus fracture should include a lateral view of the hindfoot, an anteroposterior (AP) view of the foot, a Harris axial view, and an ankle series.

• Lateral radiograph
• The Bohler tuber joint angle is composed of a line drawn from the highest point of the anterior process of the calcaneus to the highest point of the posterior facet and a line drawn tangential from the posterior facet to the superior edge of the tuberosity. The angle is normally between 20 and 40 degrees; a decrease in this angle indicates that the weight-bearing posterior facet of the calcaneus has collapsed, thereby shifting body weight anteriorly (Fig. 43).

 

Figure 43. The Bohler angle. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

 

• The Gissane (crucial) angle is formed by two strong cortical struts extending laterally, one along the lateral margin of the posterior facet and the other extending anterior to the beak of the calcaneus. These cortical struts form an obtuse angle usually between 95 and 105 degrees and are visualized directly beneath the lateral process of the talus; an increase in this angle indicates collapse of the posterior facet (Fig. 44).

• AP radiograph of the foot: This may show extension of the fracture line into the calcaneocuboid joint.

• Harris axial view

Figure 44. Angle of Gissane. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

• This is taken with the foot in dorsiflexion and the beam angled at 45 degrees cephalad.

• It allows visualization of the joint surface as well as loss of height, increase in width, and angulation of the tuberosity fragment (Fig. 45).

Figure 45. Photograph of the radiographic technique for obtaining the Harris or calcaneal radiographic view. Maximum dorsiflexion of the ankle was attempted to obtain an optimal view. (From Bucholz RW, Heckman JD, eds. Rockwood and Green’s Fractures in Adults, 5th ed. Baltimore: Lippincott Williams & Wilkins, 2002.)

• Broden views (Fig. 46)
• These are obtained with the patient supine and the x-ray cassette under the leg and the ankle. The foot is ieutral flexion, and the leg is internally rotated 30 to 40 degrees. The x-ray beam then is centered over the lateral malleolus, and four radiographs are made with the tube angled 40, 30, 20, and 10 degrees toward the head of the patient.

• These radiographs show the posterior facet as it moves from posterior to anterior; the 10-degree view shows the posterior portion of the facet, and the 40-degree view shows the anterior portion.

• It is most useful intraoperatively to assess fracture reduction.

Figure 46. Photograph of the technique to obtain the Broden view in an office setting. Technicians must angle the tube to allow for direct view of the posterior facet of the subtalar joint. (From Bucholz RW, Heckman JD, eds. Rockwood and Green’s Fractures in Adults, 5th ed. Baltimore: Lippincott Williams & Wilkins, 2002.)

• Computed tomography (CT)
• CT images are obtained in the axial, 30-degree semicoronal, and sagittal planes.

• Three- to 5-mm slices are necessary for adequate analysis.

• The coronal views provide information about the articular surface of the posterior facet, the sustentaculum, the overall shape of the heel, and the position of the peroneal and flexor hallucis tendons.

• The axial views reveal information about the calcaneocuboid joint, the anteroinferior aspect of the posterior facet, and the sustentaculum.

• Sagittal reconstruction views provide additional information on the posterior facet, the calcaneal tuberosity, and the anterior process.

CLASSIFICATION

Extraarticular Fractures

These do not involve the posterior facet. They make up 25% to 30% of calcaneus fractures.

• Anterior process fractures: These may result from strong plantar flexion and inversion, which tighten the bifurcate and interosseous ligaments leading to avulsion fracture; alternatively, they may occur with forefoot abduction with calcaneocuboid compression. They are often confused with lateral ankle sprain and are seen on lateral or lateral oblique views. Tuberosity fractures: These may result from avulsion by the Achilles tendon, especially in diabetic patients or osteoporotic women, or rarely by direct trauma; they are seen on lateral radiographs.

• Medial process fractures: These vertical shear fractures are due to loading of heel in valgus; they are seen on axial radiographs.

• Sustentacular fractures: These occur with heel loading accompanied by severe foot inversion. They are often confused with medial ankle sprain and are seen on axial radiographs.

• Body fractures not involving the subtalar articulation: These are caused by axial loading. Significant comminution, widening, and loss of height may occur along with a reduction in the BГ¶hler angle without posterior facet involvement.

Intraarticular FracturesEssex-Lopresti Classification (Fig. 47)

PRIMARY FRACTURE LINE

The posterolateral edge of the talus splits the calcaneus obliquely through the posterior facet. The fracture line exits anterolaterally at the crucial angle or as far distally as the calcaneocuboid joint. Posteriorly, the fracture moves from plantar medial to dorsal lateral, producing two main fragments: the sustentacular (anteromedial) and tuberosity (posterolateral) fragments.

• The anteromedial fragment is rarely comminuted and remains attached to the talus by the deltoid and interosseous talocalcaneal ligaments.

• The posterolateral fragment usually displaces superolaterally with variable comminution, resulting in incongruity of the posterior facet as well as heel shortening and widening.

SECONDARY FRACTURE LINE

With continued compressive forces, there is additional comminution, creating a free lateral piece of posterior facet separate from the tuberosity fragment.

• Tongue fracture: A secondary fracture line appears beneath the facet and exits posteriorly through the tuberosity.

• Joint depression fracture: A secondary fracture line exits just behind the posterior facet.

• Continued axial force causes the sustentacular fragment to slide medially, causing heel shortening and widening. As this occurs, the tuberosity fragment will rotate into varus. The posterolateral aspect of the talus will force the free lateral piece of the posterior facet down into the tuberosity fragment, rotating it as much as 90 degrees. This causes lateral wall blowout, which may extend as far anteriorly as the calcaneocuboid joint. As the lateral edge of the talus collapses further, there will be additional comminution of the articular surface.

Figure 47. Mechanism of injury according to Essex Lopresti. : Joint depression. D–F: Tongue. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Baltimore: Lippincott Williams & Wilkins, 2005.)

Sanders Classification (Fig. 48)

• This is based on CT scans.

• This classification is based on the number and location of articular fragments; it is based on the coronal image, which shows the widest surface of the inferior facet of the talus.

• The posterior facet of the calcaneus is divided into three fracture lines (A, B, and C, corresponding to lateral, middle, and medial fracture lines on the coronal image).

• Thus, there can be a total of four potential pieces: lateral, central, medial, sustentaculum tali.

Type I:	All nondisplaced fractures regardless of the number of fracture lines
Type II:	Two-part fractures of the posterior facet; subtypes IIA, IIB, IIC, based on the location of the primary fracture line
Type III:	Three-part fractures with a centrally depressed fragment; subtypes IIIAB, IIIAC, IIIBC
Type IV:	Four-part articular fractures; highly comminuted

OTA Classification of Calcaneal Fractures

See Fracture and Dislocation Compendium at http://www.ota.org/compendium/index.htm.

 

TREATMENT

Figure 48. The Sanders computed tomography scan classification of calcaneal fractures. (From Sanders R. Current concepts review: displaced intra-articular fractures of the calcaneus. J Bone Joint Surg Am 2000;82:233.)

Despite adequate reduction and treatment, fractures of the os calcis may be severely disabling injuries, with variable prognoses and degrees of functional debilitation with chronic pain issues. Treatment remains controversial, with no clear indication for operative versus nonoperative treatment.

Nonoperative

• Indications include:
• Nondisplaced or minimally displaced extraarticular fractures.

• Nondisplaced intraarticular fractures.
• Anterior process fractures with less than 25% involvement of the calcaneal-cuboid articulation.

• Fractures in patients with severe peripheral vascular disease or insulin-dependent diabetes.

• Fractures in patients with other medical comorbidities prohibiting surgery.

• Fractures associated with blistering and massive prolonged edema, large open wounds, or life-threatening injuries.

• Initial treatment is placement of a bulky Jones dressing.

• Nonoperative treatment consists of a supportive splint to allow dissipation of the initial fracture hematoma, followed by conversion to a prefabricated fracture boot locked ieutral flexion to prevent an equinus contracture and an elastic compression stocking to minimize dependent edema.

• Early subtalar and ankle joint range-of-motion exercises are initiated, and non weight-bearing restrictions are maintained for approximately 10 to 12 weeks, until radiographic union.

Operative

• Indications
• Displaced intraarticular fractures involving the posterior facet

• Anterior process of the calcaneus fractures with >25% involvement of the calcaneal-cuboid articulation

• Displaced fractures of the calcaneal tuberosity

• Fracture-dislocations of the calcaneus
• Selected open fractures of the calcaneus

• Timing of surgery
• Surgery should be performed within the initial 3 weeks of injury, before early fracture consolidation.

• Surgery should not be attempted until swelling in the foot and ankle has adequately dissipated, as indicated by the reappearance of skin wrinkles.

Specific Fractures

Extraarticular Fractures

• Anterior process fractures (Fig. 49)
• Surgical management of anterior process fractures is performed for fractures involving >25% of the calcaneal-cuboid articulation on CT scan evaluation.

• Definitive fixation involves small or minifragment screws.

• The patient may ambulate in a wooden-soled shoe, but regular shoes are not permitted for 10 to 12 weeks postoperatively.

• Tuberosity (avulsion) fractures
• These result from a violent pull of the gastrocnemius-soleus complex, such as with forced dorsiflexion secondary to a low-energy stumble and fall, producing an avulsed fragment of variable size.

• Indications for surgery: (1) the posterior skin is at risk from pressure from the displaced tuberosity, (2) the posterior portion of the bone is extremely prominent and will affect shoe wear, (3) the gastrocnemius-soleus complex is incompetent, or (4) the avulsion fragment involves the articular surface of the joint.

Figure 49. Anterior process fracture. Schematic lateral view. (From Bucholz RW, Heckman JD, eds. Rockwood and Green’s Fractures in Adults, 5th ed. Baltimore: Lippincott Williams & Wilkins, 2002.)

• Surgical treatment involves lag screw fixation with or without cerclage wire.

• Calcaneus body fractures
• True extraarticular fractures of the calcaneus, not involving the subtalar joint, probably account for 20% of all calcaneal fractures.

• Minimally displaced fractures (<1 cm) are treated with early motion and non weight bearing for 10 to 12 weeks.

• Those with significant displacement resulting in varus/valgus deformity, lateral impingement, loss of heel height, or translation of the posterior tuberosity require open reduction and internal fixation.

• Medial or lateral process fractures
• Rare and usually nondisplaced.
• The fracture is best seen on the axial radiographic view or on coronal CT scans.

• Nondisplaced fractures can be treated with a short leg weight-bearing cast until the fracture heals at 8 to 10 weeks.

• When fractures are displaced, closed manipulation may be considered.

Intraarticular Fractures

The Canadian Orthopaedic Trauma Society trial comparing operative to nonoperative treatment of displaced intraarticular calcaneal fractures found the following:

• Significantly better results occurred in certain fracture groups undergoing operative treatment

• Women
• Younger adults
• Patients with a lighter workload
• Patients not receiving Worker’s Compensation

• Patients with a higher initial Bohler angle (less severe initial injury)

• Those with an anatomic reduction on postoperative CT evaluation

• Those having nonoperative treatment of their fracture were 5.5 times more likely to require a subtalar arthrodesis for posttraumatic arthritis than those undergoing operation.

• Operative goals include:
• Restoration of congruity of the subtalar articulation.

• Restoration of the Bohler angle.

• Restoration of the normal width and height of the calcaneus.

• Maintenance of the normal calcaneocuboid articulation.

• Neutralization of the varus deformity of the fracture.

• Open reduction and internal fixation are generally performed through a lateral L-shaped incision, with care taken not to damage the sural nerve both proximally and distally.

• The posterior facet is reduced and stabilized with lag screws into the sustentaculum tali. The calcaneocuboid joint and the lateral wall are reduced. The length of the heel is regained with neutralization of varus. A thin plate is placed laterally and is used as a buttress with possible bone grafting to restore bone stock.

• Good results have been reported for tongue-type fractures using percutaneous reduction (Essex-Lopresti maneuver) and lag screw fixation (Fig. 50).

• Primary subtalar or triple arthrodesis has had good reported results for select high-energy injuries.

• Postoperative management includes:
• Early supervised subtalar range-of-motion exercises.

• Non weight bearing for 8 to 12 weeks.

• Full weight bearing by 3 months.

COMPLICATIONS

• Wound dehiscence: Most common at the angle of incision. Avoidance requires meticulous soft tissue technique and minimization of skin trauma during closure. It may be treated with wet to dry dressing changes, skin grafting, or muscle flap if necessary.

• Calcaneal osteomyelitis: The risk may be minimized by allowing soft tissue edema to resolve preoperatively.

• Posttraumatic arthritis (subtalar or calcaneocuboid): This reflects articular damage in addition to fracture displacement and comminution; thus, it may occur even in the presence of an anatomic reduction; it may be treated with injections or orthoses, or it may ultimately require subtalar or triple arthrodesis.

• Increased heel width: Some degree of heel widening is expected, even with open reduction and internal fixation. It may result in lateral impingement on the peroneal tendons or the fibula. It is aggravated by increased residual lateral width and may be treated by wall resection or hardware removal.

• Loss of subtalar motion: This is common with both operative and nonoperative treatment of intraarticular fractures.

• Peroneal tendonitis: This is generally seen following nonoperative treatment and results from lateral impingement.

• Sural nerve injury: This may occur in up to 15% of operative cases using a lateral approach.

Figure 50. Essex-Lopresti technique as modified by Tornetta. Once guide pins are correctly positioned, they are exchanged for 6.5- to 8.0-mm cannulated cancellous lag screws. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

• Chronic pain: Despite nonoperative or operative treatment of calcaneal fractures, many patients have chronic heel pain that may be debilitating; many individuals are unable to return to gainful employment.

• Reflex sympathetic dystrophy: This may occur with operative or nonoperative management.

Talus

EPIDEMIOLOGY

• These are second in frequency among all tarsal fractures.

• Two percent of all lower extremity injuries and 5% to 7% of foot injuries involve fractures of the talus.

ANATOMY (FIG. 51)

• The body of the talus is covered superiorly by articular surface through which a person’s body weight is transmitted. The anterior aspect is wider than the posterior aspect, which confers intrinsic stability to the ankle.

• Medially and laterally, the articular cartilage extends plantar to articulate with the medial and lateral malleoli, respectively. The inferior surface of the body forms the articulation with the posterior facet of the calcaneus.

• The neck of the talus is roughened by ligamentous attachments and vascular foramina. It deviates medially 15 to 25 degrees and is the most vulnerable to fracture.

• The talar head has continuous articular facets for the navicular anteriorly, the spring ligament inferiorly, the sustentaculum tali posteroinferiorly, and the deltoid ligament medially.

• There are two bony processes. The lateral process is wedge shaped and articulates with the posterior calcaneal facet inferomedially and the lateral malleolus superolaterally. The posterior process has a medial and lateral tubercle separated by a groove for the flexor hallucis longus tendon.

• An os trigonum is present in up to 50% of normal feet. It arises from a separate ossification center just posterior to the lateral tubercle of the posterior talar process.

• Sixty percent of the talus is covered by articular cartilage. No muscles originate from or insert onto the talus. The vascular supply is dependent on fascial structures to reach the talus; therefore, capsular disruptions may result in osteonecrosis.

• The vascular supply to the talus consists of:

• Arteries to the sinus tarsi (peroneal and dorsalis pedis arteries).

• An artery of the tarsal canal (posterior tibial artery).

• The deltoid artery (posterior tibial artery), which supplies the medial body.

• Capsular and ligamentous vessels and intraosseous anastomoses.

MECHANISM OF INJURY

• Most commonly associated with a motor vehicle accident or a fall from a height with a component of hyperdorsiflexion of the ankle. The talar neck fractures as it impacts the anterior margin of the tibia.

• Aviator’s astragalus: This historical term refers to the rudder bar of a crashing airplane impacting the plantar aspect of the foot, resulting in a talar neck fracture.

Figure 51. Superior and inferior views of the talus (stippling indicates the posterior and lateral processes). (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

CLINICAL EVALUATION

• Patients typically present with foot pain.

• Range of foot motion is typically painful and may elicit crepitus.

• Diffuse swelling of the hindfoot may be present, with tenderness to palpation of the talus and subtalar joint.

• Associated fractures of the foot and ankle are commonly seen with fractures of the talar neck and body.

RADIOGRAPHIC EVALUATION

• Anteroposterior (AP), mortise, and lateral radiographs of the ankle, as well as AP, lateral, and oblique views of the foot are obtained.

• Canale view: This provides an optimum view of the talar neck. Taken with the ankle in maximum equinus, the foot is placed on a cassette, pronated 15 degrees, and the radiographic source is directed cephalad 15 degrees from the vertical (Fig. 52).

• Computed tomography (CT) is helpful to characterize fracture pattern and displacement further and to assess articular involvement.

• Technetium bone scans or magnetic resonance imaging (MRI) may be useful in evaluating possible occult talar fractures.

Figure 52. Canale and Kelly view of the foot. The correct position of the foot for x-ray evaluation of the foot is shown. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

 

CLASSIFICATION

Anatomic

• Lateral process fractures
• Posterior process fractures
• Talar head fractures
• Talar body fractures
• Talar neck fractures

Classification of Talar Neck Fractures (Figs. 53 and 54)

Hawkins Type I:	Nondisplaced
Type II:	Associated subtalar subluxation or dislocation
Type III:	Associated subtalar and ankle dislocation
Type IV:	(Canale and Kelley): type III with associated talonavicular subluxation or dislocation

OTA Classification of Talar Fractures

See Fracture and Dislocation Compendium at http://www.ota.org/compendium/index.htm.

TREATMENT

Fractures of the Talar Neck and Body

These represent a continuum and are considered together.

Nondisplaced Fractures (Hawkins Type I)

• Fractures that appear nondisplaced on plain radiographs may show unrecognized comminution or articular step-off on CT scan. Fractures must truly be nondisplaced with no evidence of subtalar incongruity to be considered a type I fracture.

• Treatment consists of a short leg cast or boot for 8 to 12 weeks. The patient should remaion weight bearing for 6 weeks until clinical and radiographic evidence of fracture healing is present.

Displaced Fractures (Hawkins Types II to IV)

• Immediate closed reduction is indicated, with emergency open reduction and internal fixation (ORIF) for all open or irreducible fractures.

Figure 53. The three patterns of talar neck fractures as described by Hawkins. Note that type I fractures are nondisplaced. (A) Type I talar neck fractures with no displacement. (B) Type II talar neck fractures with displacement and subluxation of subtalar joint. (C) Type III talar neck fracture with displacement and dislocation of both ankle and subtalar joints. (From Bucholz RW, Heckman JD, eds. Rockwood and Green’s Fractures in Adults, 5th ed. Baltimore: Lippincott Williams & Wilkins, 2002.)

Figure 54. Type IV fracture of the talar neck with subluxation of the subtalar joint and dislocation of the talonavicular joint. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

• If anatomic reduction is obtained and confirmed by CT scan, the patient should be placed in a short leg cast, with treatment as for nondisplaced fractures.

• If open reduction is necessary, all major fragments should be salvaged. Primary arthrodesis should be avoided.
• Surgical approaches include:
• Anteromedial: This approach may be extended from a limited capsulotomy to a wide exposure with malleolar osteotomy. The internal is just medial to the anterior tibial tendon. This approach allows visualization of the talar neck and body. Care must be taken to preserve the saphenous vein and nerve and, more importantly, the deltoid artery.

• Posterolateral: This approach provides access to posterior process and talar body. The interval is between the peroneus brevis and the flexor hallucis longus. The sural nerve must be protected. It is usually necessary to displace the flexor hallucis longus from its groove in the posterior process to facilitate exposure.

• Anterolateral: This approach allows visualization of the sinus tarsi, lateral talar neck, and subtalar joint. Inadvertent damage to the artery of the tarsal sinus can occur through this approach.

• Combined anteromedial-anterolateral: This is often used to allow maximum visualization of the talar neck.

• Internal fixation: Two interfragmentary lag screws or headless screws are placed perpendicular to the fracture line. The screws can be inserted in antegrade or retrograde fashion. Posterior-to-anterior directed screws have been demonstrated to be biomechanically stronger.

• Use of titanium screws allows better visualization with MRI for evaluation of subsequent osteonecrosis.

• Areas of significant comminution and bone loss should be grafted.

• A plate can be used to buttress areas of comminution.

• A short leg cast or removable boot should be placed postoperatively for 8 to 12 weeks, and the patient should be kept non weight bearing.

• Hawkins sign: Subchondral osteopenia (seen on the AP ankle radiograph) in the talus at 6 to 8 weeks tends to indicate talar viability. However, the presence of this sign does not rule out osteonecrosis; its absence is also not diagnostic for osteonecrosis.

Lateral Process Fractures

These are intraarticular fractures of the subtalar or ankle joint that occur most frequently when the foot is dorsiflexed and inverted. There has been an increase in incidence with the rise in popularity of snowboarding.

• Lateral process fractures are often missed on initial patient presentation. Fracture is misinterpreted as a severe ankle sprain.
• Because of the difficulty in detecting and defining the extent of a lateral process fracture, a CT scan is frequently necessary to fully appreciate the extent of injury.

• Less 2 mm displacement: Patients should have a short leg cast or boot for 6 weeks and be non weight bearing for at least 4 weeks.

• More than 2 mm displacement: ORIF is performed using lag screws or wires through a lateral approach.

• Comminuted fractures: Nonviable fragments are excised.

Posterior Process Fractures

These involve the posterior 25% of the articular surface and include the medial and lateral tubercles. Fractures may occur in a severe ankle inversion injury whereby the posterior talofibular ligament avulses the lateral tubercle or by forced equinus and direct compression.

• Diagnosis of fractures of the posterior process of the talus can be difficult, in part relating to the presence of an os trigonum.

• Nondisplaced or minimally displaced: Patients should have a short leg cast for 6 weeks and be non weight bearing for at least 4 weeks.

• Displaced: ORIF is recommended if the fragment is large; primary excision is performed if the fragment is small; a posterolateral approach may be used.

Talar Head Fractures

These fractures result from plantarflexion and longitudinal compression along the axis of the forefoot. Comminution is common; one must also suspect navicular injury and talonavicular disruption.

• Nondisplaced fractures: Patients should be placed in a short leg cast molded to preserve the longitudinal arch and should be partially weight bearing for 6 weeks. An arch support is worn in the shoe to splint the talonavicular articulation for 3 to 6 months.

• Displaced fractures: ORIF is indicated, with primary excision of small fragments through an anterior or anteromedial approach.

COMPLICATIONS

• Infection: The risk may be minimized by early ORIF with soft tissue coverage for open injuries or waiting until swelling has decreased.

• Osteonecrosis: The rate of osteonecrosis is related to initial fracture displacement:

Hawkins I:	0% to 15%
Hawkins II:	20% to 50%
Hawkins III:	20% to 100%
Hawkins IV:	100%

• Posttraumatic arthritis: This occurs in 40% to 90% of cases, typically related to articular incongruity or chondral injury at the time of fracture. This may be evident in either the ankle or subtalar joints. The rates of arthritis in the subtalar joint, ankle joint, or both joints are 50%, 30%, and 25%, respectively.

• Delayed union and nonunion: Delayed union (>6 months) may occur in up to 15% of cases. It may be treated by open reduction and bone grafting.

• Malunion: Commonly varus, this is related to initial fracture reduction associated with dorsomedial comminution. Malunion results in subtalar stiffness and excessive weight bearing on the lateral side of the foot; malunion is frequently painful.

• Open fracture: This complicates up to 15% to 25% of injuries and reflects the often high-energy mechanism that produces these fractures. Copious irrigation and meticulous debridement are necessary to prevent infectious complications. The reported infection rate for open talus fractures is 35% to 40%.

• Skin slough: This may occur secondary to prolonged dislocation, with pressure necrosis on the overlying soft tissues. When severe, it may result in pressure erosion, compromising soft tissue integrity and resulting in possible infection.

• Interposition of long flexor tendons: This may prevent adequate closed reduction and necessitate ORIF.

• Foot compartment syndrome: Rare. However, pain on passive extension of the toes must raise clinical suspicion of possible evolving or present compartment syndrome of the foot, particularly in a patient in whom symptoms are out of proportion to the apparent injury. Emergency fasciotomy is indicated.

Subtalar Dislocation

• Subtalar dislocation, also known as peritalar dislocation, refers to the simultaneous dislocation of the distal articulations of the talus at the talocalcaneal and talonavicular joints.

• It most commonly occurs in young men.

• Inversion of the foot results in a medial subtalar dislocation, whereas eversion produces a lateral subtalar dislocation.

• Up to 85% of dislocations are medial.

• Lateral dislocations are often associated with a higher-energy mechanism and a worse long-term prognosis compared with medial subtalar dislocations.

• All subtalar dislocations require gentle and timely reduction.

• Reduction involves sufficient analgesia with knee flexion and longitudinal foot traction. Accentuation of the deformity is ofteecessary to “unlock” the calcaneus. Once the calcaneus is unlocked, reversal of the deformity can be applied. Reduction is usually accompanied by a satisfying clunk.
• In many cases, a subtalar dislocation is stable following closed reduction.

• CT scan is useful after closed reduction to determine whether associated fractures are present and to detect possible talocalcaneal subluxation.

• A variety of bone and soft tissue structures may become entrapped, resulting in a block to closed reduction. With medial dislocations, the talar head can become trapped by the capsule of the talonavicular joint, the extensor retinaculum or extensor tendons, or the extensor digitorum brevis muscle. With a lateral dislocation, the posterior tibial tendon when entrapped may present a substantial barrier even to open reduction (Fig. 55).

Figure 55. Lateral subtalar dislocation with interposed posterior tibial tendon preventing closed reduction. (Adapted from Leitner B. Obstacles to reduction in subtalar dislocations. J Bone Joint Surg Am 1954;36:299.)

• Open reduction, wheecessary, is usually performed through a longitudinal anteromedial incision for medial dislocations and a sustentaculum tali approach for lateral dislocations.

• Following a short period of immobilization, physical therapy is instituted to regain subtalar and midtarsal mobility.

Total Dislocation of the Talus

• Total dislocation of the talus is a rare injury, resulting from an extension of the forces causing a subtalar dislocation.

• Most injuries are open.
• Initial treatment is directed to the soft tissues.

• In general, open reduction of the completely dislocated talus is required.

• Results may be complicated by infection, osteonecrosis, and posttraumatic arthritis.

Fractures of the Midfoot and Forefoot

MIDTARSAL JOINT (CHOPART JOINT)

Epidemiology

• Injuries to the midfoot are relatively rare.

Anatomy

• The midfoot is the section of the foot distal to Chopart joint line and proximal to Lisfranc joint line (Fig. 56).

• Five bones comprise the midfoot: the navicular, cuboid, and the medial, middle, and lateral cuneiforms.

• The midtarsal joint consists of the calcaneocuboid and talonavicular joints, which act in concert with the subtalar joint during inversion and eversion of the foot.

• The cuboid acts as a linkage across the three naviculocuneiform joints, allowing only minimal motion.

• Ligamentous attachments include the plantar calcaneonavicular (spring) ligament, bifurcate ligament, dorsal talonavicular ligament, dorsal calcaneocuboid ligament, dorsal cuboidonavicular ligament, and long plantar ligament (Fig. 57).

Mechanism of Injury

• High-energy trauma: This is most common and may result from direct impact from a motor vehicle accident or a combination of axial loading and torsion, such as during impact from a fall or jump from a height.

• Low-energy injuries: This may result in a sprain during athletic or dance activities.

Clinical Evaluation

• Patient presentation is variable, ranging from a limp with swelling and tenderness on the dorsum of the midfoot to nonambulatory status with significant pain, gross swelling, ecchymosis, and variable deformity.

• Stress maneuvers consist of forefoot abduction, adduction, flexion, and extension and may result in reproduction of pain and instability.

• A careful neurovascular examination should be performed. In cases of extreme pain and swelling, serial examinations may be warranted to evaluate the possibility of foot compartment syndrome.

Radiographic Evaluation

• Anteroposterior (AP), lateral, and oblique radiographs of the foot should be obtained.

• Stress views or weight-bearing x-rays may help to delineate subtle injuries.

• Computed tomography (CT) may be helpful in characterizing fracture-dislocation injuries with articular comminution.

Figure 56. Bony anatomy of the midfoot. (A) Dorsal view. (B) Plantar view. (C) Medial view. (D) Lateral view. (E) Coronal view. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

• Magnetic resonance imaging (MRI) may be used to evaluate ligamentous injury.

Classification

Medial Stress Injury (30%)

• Inversion injury occurs with adduction of the midfoot on the hindfoot.

• Flake fractures of the dorsal margin of the talus or navicular and of the lateral margin of the calcaneus or the cuboid may indicate a sprain.

• In more severe injuries, the midfoot may be completely dislocated, or there may be an isolated talonavicular dislocation. A medial swivel dislocation is one in which the talonavicular joint is dislocated, the subtalar joint is subluxed, and the calcaneocuboid joint is intact.

Figure 57. Ligamentous structure of the midfoot. (A) The dorsal view shows extensive overlap of the interosseous ligaments. (B) The plantar ligaments are thicker than their dorsal counterparts and are dynamically reinforced by the tibialis anterior, tibialis posterior, and peroneus longus tendons. Note the extensive attachments of the tibialis posterior throughout the midfoot bones. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

 

Longitudina Stress Injury (41%)

• Force is transmitted through the metatarsal heads proximally along the rays with resultant compression of the midfoot between the metatarsals and the talus with the foot plantar flexed.

• Longitudinal forces pass between the cuneiforms and fracture the navicular typically in a vertical pattern.

Lateral Stress Injury (17%)

• Nutcracker fractures: This is the characteristic fracture of the cuboid as the forefoot driven laterally, crushing the cuboid between the calcaneus and the fourth and fifth metatarsal bases.

• Most commonly, this is an avulsion fracture of the navicular with a comminuted compression fracture of the cuboid.

• In more severe trauma, the talonavicular joint subluxes laterally, and the lateral column of the foot collapses because of comminution of the calcaneocuboid joint.

Plantar Stress Injury (7%)

• Forces directed at the plantar region may result in sprains to the midtarsal region with avulsion fractures of the dorsal lip of the navicular, talus, or anterior process of the calcaneus.

Treatment

Nonoperative

• Sprains: Nonrigid dressings are used with protected weight bearing for 4 to 6 weeks; prognosis is excellent.

• Nondisplaced fractures may be treated with a short leg cast or boot with initial non weight bearing for 6 weeks.

Operative

• High-energy mechanisms resulting in displaced fracture patterns often require open reduction and internal fixation (ORIF; e.g., with Kirschner wires or lag screws) and/or external fixation.

• Prognosis is often poor, depending on the degree of articular incongruity.

• Bone grafting of the cuboid may be necessary in lateral stress injuries.

• Severe crush injuries with extensive comminution may require arthrodesis to restore the longitudinal arch of the foot.

Complications

• Posttraumatic osteoarthritis may occur as a result of residual articular incongruity or chondral injury at the time of trauma. If severe and debilitating, it may require arthrodesis for adequate relief of symptoms.

TARSAL NAVICULAR

Epidemiology

• Isolated fractures of the navicular are rare and should be diagnosed only after ruling out concomitant injuries to the midtarsal joint complex.

Anatomy

• The navicular is the keystone of the medial longitudinal arch of the foot.

• It is wider on its dorsal and medial aspect than on its plantar and lateral aspect.

• The medial prominence known as the navicular tuberosity provides the attachment point for the posterior tibialis on its medial inferior surface.

• Proximally, the articular surface is concave and articulates with the talus. This joint enjoys a significant arc of motion and transmits the motion of the subtalar joint to the forefoot. It is the point from which forefoot inversion and eversion are initiated.

• The distal articular surface of the navicular has three separate broad facets that articulate with each of the three cuneiforms. These joints provide little motion; they mainly dissipate loading stresses.

• Laterally, the navicular rests on the dorsal medial aspect of the cuboid with a variable articular surface.

• Thick ligaments on its plantar and dorsal aspect support the navicular cuneiform joints. The spring ligament and superficial deltoid provide strong support to the plantar and medial aspects of the talonavicular joint.

• Anatomic variants to be aware of when viewing the navicular involve the shape of the tuberosity and the presence of an accessory navicular (os tibiale externum). They are present up to 15% of the time and bilateral 70% to 90%.

Mechanism of Injury

• Direct blow, although uncommon, can cause avulsions to the periphery or crush injury in the dorsal plantar plane.

• More often, indirect forces of axial loading either directly along the long axis of the foot or obliquely cause navicular injury.

• Injury may result from a fall from a height or a motor vehicle accident. Fractures may occur in running and jumping athletes, with increased risk in patients with a cavus foot or calcaneal navicular coalition.

Clinical Evaluation

• Patients typically present with a painful foot and dorsomedial swelling and tenderness.

• Physical examination should include assessment of the ipsilateral ankle and foot, with careful palpation of all bony structures to rule out associated injuries.

Radiographic Evaluation

• AP, lateral, medial oblique and lateral oblique views should be obtained to ascertain the extent of injury to the navicular as well as to detect associated injuries.

• If possible, the initial films should be weight bearing to detect ligamentous instability.

• Medial and lateral oblique x-rays of the midfoot will aid in assessing the lateral pole of the navicular as well as the medial tuberosity.

• CT may be obtained to better characterize the fracture.

 MRI or technetium scan may be obtained if a fracture is suspected but not apparent by plain radiography.

Classification

• The most commonly used classification of navicular fractures is composed of three basic types with a subclassification for body fractures (Sangeorzan) (Fig. 58).

• Avulsion-type fracture can involve either the talonavicular or naviculocuneiform ligaments.

• Tuberosity fractures are usually traction type injuries with disruption of the tibialis posterior insertion without joint surface disruption.

• Type I body fracture splits the navicular into dorsal and plantar segments.

• Type II body fractures cleave into medial and lateral segments. The location of the split usually follows either of the two intercuneiform joint lines. Stress fractures can usually be included in this group.
• Type III body fractures are distinguished by comminution of the fragments and significant displacement of the medial and lateral poles.

Figure 58. The present popular classification of navicular fractures is composed of three basic types with a subclassification for body fractures suggested by Sangeorzan. (A) Avulsion-type fracture can involve either the talonavicular or naviculocuneiform ligaments. (B) Tuberosity fractures are usually traction-type injuries with disruption of the tibialis posterior insertion without joint surface disruption. (C) A Type I body fracture splits the navicular into dorsal and plantar segments. (D) A Type II body fracture cleaves into medial and lateral segments. The location of the split usually follows either of the two intercuneiform joint lines. Stress fractures are usually included in this group. (E) A Type III body fracture is distinguished by comminution of the fragments and significant displacement of the medial and lateral poles. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

 

OTA Classification of Navicular Fractures

See Fracture and Dislocation Compendium at http://www.ota.org/compendium/index.htm.

Anatomic Classification

CORTICAL AVULSION FRACTURES (45% TO 50%)

• Excessive flexion or eversion of midfoot results in a dorsal lip avulsion of the navicular by the talonavicular capsule and the anterior fibers of the deltoid ligament.

• Symptomatic, small, nonarticular fragments may be excised. Large fragments (>25% articular surface) may be reattached with a lag screw.

BODY FRACTURES (30%)
TUBEROSITY FRACTURES (20% TO 25%)

• Forced eversion injury causes avulsion of the tuberosity by the posterior tibial tendon insertion or deltoid ligament.

• This is often part of the nutcracker fracture, so concomitant midtarsal injury must be excluded.

• One must rule out the presence of an accessory navicular, which is bilateral in 70% to 90% of cases.

• If symptomatic, small fragments can be excised and the posterior tibial tendon reattached; larger fragments require ORIF with lag screw fixation, especially if posterior tibial tendon function is compromised.

STRESS FRACTURES

• These occur primarily in young athletes.

• They frequently require bone scan or MRI for diagnosis.

• The fracture line is usually sagittally oriented in the middle third and may be complete or incomplete.

• Owing to increased incidence of persistent problems with pain and healing, screw fixation with autologous bone grafting should be used with comminuted fractures.

Treatment

The two most important criteria in obtaining a satisfactory outcome are maintenance or restoration of the medial column length and articular congruity of the talonavicular joint.

Nonoperative

• Nondisplaced fractures of the navicular should be treated in a short leg cast or boot with non–weight bearing for 6 to 8 weeks.

• Repeat radiographs should be done at 10 to 14 days after the initial injury to confirm the absence of bony or soft tissue instability. If instability appears or other injuries become apparent, appropriate surgical intervention should be considered.

Operative

• Surgical indications
• Any unstable injury or fracture resulting in loss of position or articular congruity should be treated surgically.

• Because the joint is concave, a 2-mm separation in any plane is considered incongruent. Most authors agree these injuries need to be managed aggressively with surgery.

• Cortical avulsion fractures found to involve a significant portion of the dorsal anterior surface should be considered for operative treatment.

• Surgical management
• Individual fragments are stabilized using small or minifragment screws.

• Bone graft should be considered for crushed areas requiring elevation.

• If anatomic restoration of 60% or more of the talonavicular surface can be achieved, an effort should be made to salvage the joint.

• If more than 40% of the articular surface cannot be reconstructed, an acute talonavicular fusion should be considered.

• Postoperative management
• Cast or brace immobilization with non–weight bearing is recommended for 12 weeks.

Complications

• These include nonunion, arthritic degeneration, late instability, loss of normal foot alignment through bony resorption or collapse, and osteonecrosis.

• Osteonecrosis: The risk is increased with significantly displaced, markedly comminuted fractures. It may result in collapse of the navicular, with need for bone grafting and internal fixation.

• Posttraumatic osteoarthritis may occur as a result of articular incongruity, chondral damage, or free osteochondral fragments.

NAVICULAR DISLOCATION

• Isolated dislocation or subluxation of the navicular is rare.

• The mechanism is hyperplantar flexion of the forefoot with subsequent axial loading.

• Open reduction is usually necessary to restore both navicular position and articular congruity.

CUBOID FRACTURES

Epidemiology

• Injury to the cuboid can occur as an isolated entity but is usually seen in association with injuries to the talonavicular joint or other midfoot structures or in conjunction with Lisfranc injuries.

Anatomy

• The cuboid is part of the lateral support column of the foot.

• The cuboid articulates with the calcaneus proximally, the navicular and lateral cuneiform medially, and the lateral two metatarsals distally.

• Its plantar aspect forms a portion of the roof of the peroneal groove through which the peroneus longus tendon runs; scarring and irregularity of the peroneal groove caused by cuboid fracture may compromise function of peroneus longus tendon.

Mechanism of Injury

• Direct: This is uncommon; trauma to the dorsolateral aspect of the foot may result in fractures of the cuboid.

• Indirect: This accounts for most cuboid fractures.

• Nutcracker injury: Torsional stress or forefoot abduction may result in impaction of the cuboid between the calcaneus and the lateral metatarsals.

• Extreme plantar flexion may cause isolated sprain or dislocation of calcaneocuboid joint in high-velocity trauma, dance injuries, or patients with Ehlers-Danlos syndrome.

• Stress fractures may occur in athletic individuals.

Clinical Evaluation

• Patients typically present with pain, swelling, and tenderness to palpation at the dorsolateral aspect of the foot.

• Palpation of all bony structures of the foot should be performed to rule out associated injuries.

• Pain on the lateral aspect of the foot may be confused with symptoms of peroneal tendonitis in cases of stress fractures of the cuboid.

Radiographic Evaluation

• AP, lateral, and oblique views of the foot should be obtained.

• Multiple medial oblique radiographic views may be needed to see the articular outlines of both the calcaneocuboid and cuboid metatarsal joints.

• As with other potential midfoot problems, weight-bearing or stress views should be obtained to rule out interosseus instability of surrounding structures.

• A small medial or dorsal avulsion fracture of the navicular is considered a sign of possible cuboid injury.

• CT scan may be necessary to assess the extent of injury and instability.

• MRI or bone scan may be used for diagnosing a stress fracture.

Classification

OTA Classification

See Fracture and Dislocation Compendium at http://www.ota.org/compendium/index.htm.

Treatment

Nonoperative

• Isolated fractures of the cuboid with no evidence of loss of osseous length or interosseus instability can be treated in a cast or removable boot.

• Non–weight bearing for 4 to 6 weeks is recommended.

Operative

• ORIF is indicated if there is more than 2 mm of joint surface disruption or any evidence of longitudinal compression.

• Severe comminution and residual articular displacement may necessitate calcaneocuboid arthrodesis for proper foot alignment and to minimize late complications.

Complications

• Osteonecrosis: This may complicate severely displaced fractures or those with significant comminution.

• Posttraumatic osteoarthritis: This may result from articular incongruity, chondral damage, or free osteochondral fragments.

• Nonunion: This may occur with significant displacement and inadequate immobilization or fixation. If severely symptomatic, it may necessitate ORIF with bone grafting.

CUNEIFORM FRACTURES

• These usually occur in conjunction with tarsometatarsal injuries.

• The usual mechanism is indirect axial loading of the bone.

• Localized tenderness over the cuneiform region, pain in the midfoot with weight bearing, or discomfort with motion through the tarsometatarsal joints can signify injury to these bones.

• AP, lateral, and oblique views should be obtained. These should be weight bearing if possible.

• Coronal and longitudinal CT scan of the midfoot can be used to better define the extent of the injury.

OTA Classification of Cuneiform Fractures

See Fracture and Dislocation Compendium at http://www.ota.org/compendium/index.htm.

TARSOMETATARSAL (LISFRANC) JOINT

Epidemiology

• These are generally considered rare.

• Approximately 20% of Lisfranc injuries may be initially overlooked (especially in polytraumatized patients).

Anatomy (Fig. 59)

• In the AP plane, the base of the second metatarsal is recessed between the medial and lateral cuneiforms. This limits translation of the metatarsals in the frontal plane.

• In the coronal plane, the middle three metatarsal bases are trapezoidal, forming a transverse arch that prevents plantar displacement of the metatarsal bases. The second metatarsal base is the keystone in the transverse arch of the foot.

• There is only slight motion across the tarsometatarsal joints, with 10 to 20 degrees of dorsal plantar motion at the fifth metatarsocuboid joint and progressively less motion medially except for the first metatarsocuneiform (20 degrees of plantar flexion from neutral).

• The ligamentous support begins with the strong ligaments linking the bases of the second through fifth metatarsals. The most important ligament is Lisfranc ligament, which attaches the medial cuneiform to the base of the second metatarsal.

Figure 59. The anatomy of the tarsometatarsal joints. (A) Proximal view of the cuneiform and cuboid articular surfaces. (B) Distal view of the corresponding articular surfaces of the metatarsals. (C) Schematic representation of the contour of the tarsometatarsal joint line. Note the keying in place of the base of the second metatarsal. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

• Ligamentous, bony, and soft tissue support provides for intrinsic stability across the plantar aspect of Lisfranc joint; conversely, the dorsal aspect of this articulation is not reinforced by structures of similar strength.

• There is no ligamentous connection between the base of the first and second metatarsals.

• The dorsalis pedis artery dives between the first and second metatarsals at Lisfranc joint and may be damaged during injury or reduction.

Mechanism of Injury

Three most common mechanisms include:

• Twisting: Forceful abduction of the forefoot on the tarsus results in fracture of the base of the second metatarsal and shear or crush fracture of the cuboid. Historically, this was seen in equestrian accidents when a rider fell from a horse with a foot engaged in a stirrup. It is commonly seen today in motor vehicle accidents.

• Axial loading of a fixed foot may be seen with (1) extrinsic axial compression applied to the heel such as a heavy object striking the heel of a kneeling patient or (2) extreme ankle equinus with axial loading of the body weight, such as a missed step off a curb or landing from a jump during a dance maneuver.

• Crushing mechanisms are common in industrial-type injuries to Lisfranc joint, often with sagittal plane displacement, soft tissue compromise, and compartment syndrome.

Clinical Evaluation

• Patients present with variable foot deformity, pain, swelling, and tenderness on the dorsum of the foot.

• Diagnosis requires a high degree of clinical suspicion.

• Twenty percent are misdiagnosed.
• Forty percent have no treatment in the first week.

• Be wary of the diagnosis of midfoot sprain.

• A careful neurovascular examination is essential, because dislocation of Lisfranc joint may be associated with impingement on or partial or complete laceration of the dorsalis pedis artery. In addition, dramatic swelling of the foot is common with high-energy mechanisms; compartment syndrome of the foot must be ruled out on the basis of serial neurovascular examination or compartment pressure monitoring if necessary.

• Stress testing may be performed by gentle passive forefoot abduction and pronation, with the hindfoot firmly stabilized in the examiner’s other hand. Alternatively, pain can typically be reproduced by gentle supination and pronation of the forefoot.

Radiographic Evaluation

Standard AP, lateral, and oblique films are usually diagnostic.

• The medial border of the second metatarsal should be colinear with the medial border of the middle cuneiform on the AP view (Fig. 60).

• The medial border of the fourth metatarsal should be colinear with the medial border of the cuboid on the oblique view (Fig. 61).

• Dorsal displacement of the metatarsals on the lateral view is indicative of ligamentous compromise.

• Flake fractures around the base of the second metatarsal are indicative of disruption of Lisfranc joint.

• Weight-bearing radiographs provide a stress film of the joint complex.

• If clinically indicated, physician-directed stress views should be obtained. The forefoot is held in abduction for the AP view and in plantar flexion for the lateral view.

• 
  
  A CT

  scan can be used to assess the plantar osseous structures as well as the amount of intraarticular comminution.

Figure 60. Anteroposterior view of the tarsometatarsal joint. Normal joint alignment on weight bearing. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

 

Figure 61. Medial oblique view of the tarsometatarsal joint. Normal joint alignment on weight bearing. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

 

Associated Injuries

• Fractures of the cuneiforms, cuboid, and/or metatarsals are common.

The second metatarsal is the most frequent associated fracture. Classification

Classification schemes for Lisfranc injuries guide the clinician in defining the extent and pattern of injury, although they are of little prognostic value.

 

Ouenu and Kuss (Fig. 62)

This classification is based on commonly observed patterns of injury.

 

Myerson (Fig. 63)

This is based on commonly observed patterns of injury with regard to treatment.

 

Treatment

 

Nonoperative

• Injuries that present with painful weight bearing, pain with metatarsal motion, and tenderness to palpation but fail to exhibit any instability should be considered a sprain.

• Patients with nondisplaced ligamentous injuries with or without small plantar avulsion fractures of the metatarsal or tarsal bones should be placed in a well-molded short leg cast or removable boot.

• Initially, the patient is kept non–weight bearing with crutches and is permitted to bear weight as comfort allows.

• Repeat x-rays are necessary once swelling decreases, to detect osseous displacement.

Operative

• This should be considered when displacement of the tarsometatarsal joint is >2 mm.

• The best results are obtained through anatomic reduction and stable fixation.

The most common approach is using two longitudinal incisions. The first is centered over the first/second intermetatarsal space allowing identification of the neurovascular bundle and access to the medial two tarsometatarsal joints. A second longitudinal incision is made over the fourth metatarsal.

Figure 62. The common classification devised by Quenu and Kuss. Further subdivisions are used to identify the direction of dislocation in the homolateral pattern (medial or lateral) and the partial disruption (first or lesser). (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

Figure 63. Myerson classification of Lisfranc fracture-dislocations. (From Myerson MS, Fisher RT, Burgess AR, et al. Fracture-dislocations of the tarsometatarsal joints: end results correlated with pathology and treatment. Foot Ankle 1986;6:225–242.)

• The key to reduction is correction of the fracture-dislocation of the second metatarsal base. Clinical results suggest that accuracy and maintenance of reduction are of utmost importance and correlate directly with the overall outcome.

• Once reduction is accomplished, screw fixation is advocated for the medial column.

• The lateral metatarsals frequently reduce with the medial column, and Kirschner wire fixation is acceptable.

• If intercuneiform instability exists, one should use an intercuneiform screw.

• Stiffness from ORIF is not of significant concern because of the already limited motion of the tarsometatarsal joints.

Postoperative Management

• The foot is immobilized in a non weight-bearing cast or boot for 6 to 8 weeks.

• Progressive weight bearing is then permitted as comfort allows.

• Advancement out of cast immobilization is done once pain-free, full weight bearing is achieved.

• Lateral column stabilization can be removed at 6 to 12 weeks.

• Medial fixation should not be removed for 4 to 6 months.

• Some advocate leaving screws indefinitely unless symptomatic.

Complications

• Posttraumatic arthritis
• Present in most, but may not be symptomatic

• Related to initial injury and adequacy of reduction

• Treated with arthrodesis for the medial column

• Possibly treated with interpositional arthroplasty for the lateral column

• Compartment syndrome
• Infection
• Complex mediated regional pain syndrome (RSD)

• Neurovascular injury
• Hardware failure

FRACTURES OF THE FOREFOOT

• The forefoot serves two purposes during gait.

• As a unit, it provides a broad plantar surface for load sharing. Weight-bearing studies show that the two sesamoids and the four lesser metatarsal heads share an equal amount of the forefoot load iormal gait.

• The forefoot is mobile in the sagittal plane. This enables the forefoot to alter the position of the individual metatarsal heads to accommodate uneven ground.

Metatarsals

Epidemiology

• This is a common injury; however, the true incidence of metatarsal shaft fractures is unknown, owing to the variety of physicians treating such injuries.

Anatomy

• Displaced fractures of the metatarsals result in the disruption of the major weight-bearing complex of the forefoot.

• Disruptions produce an alteration in the normal distribution of weight in the forefoot and lead to problems of metatarsalgia and transfer lesions (intractable plantar keratoses).

Mechanism of Injury

• Direct: This most commonly occurs when a heavy object is dropped on the forefoot.

• Twisting: This occurs with body torque when the toes are fixed, such as when a person catches the toes in a narrow opening with continued ambulation.

• Avulsion: This occurs particularly at the base of the fifth metatarsal.

• Stress fractures: These occur especially at the necks of the second and third metatarsals and the proximal fifth metatarsal.

Clinical Evaluation

• Patients typically present with pain, swelling, and tenderness over the site of fracture.

• Neurovascular evaluation is important, as well as assessment of soft tissue injury and ambulatory capacity.

Radiographic Evaluation

• In isolated injuries to the foot, weight-bearing films should be obtained in the AP and lateral planes.

• The lateral radiographic view of the metatarsals is important for judging sagittal plane displacement of the metatarsal heads.

• Oblique views can be helpful to detect minimally displaced fractures.

• Except in the case of an isolated direct blow, initial films should include the whole foot to rule out other potential collateral injuries that may also require attention.

• MRI and technetium bone scan may aid in the diagnosis of an occult stress fracture.

Classification

OTA CLASSIFICATION

See Fracture and Dislocation Compendium at http://www.ota.org/compendium/index.htm.

Specific Metatarsal Injuries

FIRST METATARSAL INJURIES

• This bone is larger and stronger than the lesser metatarsals and is less frequently injured.

• The lack of interconnecting ligaments between the first and second metatarsal bones allows independent motion.

• The first metatarsal head supports two sesamoid bones, which provide two of the six contact points of the forefoot.

• Injuries usually relate to direct trauma (often open and/or comminuted).

• Anatomic reduction and stable fixation are important.

• The best way to determine operative or nonoperative treatment is with stress radiographs. Manual displacement of the position of the first metatarsal through the joint or fracture site represents instability that requires fixation.

• If no evidence of instability can be seen on stress films, and no other injury of the midfoot or metatarsals is evident, isolated first metatarsal fractures can be adequately treated with a short leg cast or removable boot with weight bearing as tolerated for 4 to 6 weeks.

• Malunion, nonunion, and arthritic degeneration of the tarsometatarsal and metatarsophalangeal (MTP) joints are all possible complications of first metatarsal fractures. Transfer metatarsalgia to the lesser toes can occur with shortening of the metatarsal length.

SECOND, THIRD, AND FOURTH METATARSAL INJURIES

• The four lesser metatarsals provide only one contact point each on the plantar weight-bearing surface.

• Significant ligamentous structures link each of the bones to their adjacent neighbors.

• Fractures of the central metatarsals are much more common than first metatarsal fractures and can be isolated or part of a more significant injury pattern.

• Indirect twisting mechanisms may result in a spiral pattern. One must be wary of Lisfranc injury with involvement of base of second metatarsal.

• Most isolated individual central metatarsal fractures can be treated closed with hard-soled shoes and progressive weight bearing as tolerated.

• The surgical criterion most often mentioned is any fracture displaying more than 10 degrees of deviation in the dorsal plantar plane or 3 to 4 mm translation in any plane.

• Complications of treating central metatarsal fractures usually stem from incomplete restoration of plantar anatomy.

FIFTH METATARSAL INJURIES

• These usually result from direct trauma.

• Fractures are separated roughly into two groups, proximal base fractures and distal spiral fractures.

• Proximal fifth metatarsal fractures are further divided by the location of the fracture and the presence of prodromal symptoms (Fig. 64).

• Zone 1: cancellous tuberosity (93%)
• Insertion of the peroneal brevis and plantar fascia

• Involvement of the metatarsocuboid joint
• Zone 2: distal to the tuberosity (4%)

• Zone 3: distal to the proximal ligaments (3%)

• Extension to the diaphysis for 1.5 cm

• Usually stress fractures
• Zone 1 injury
• This results from avulsion from lateral plantar aponeurosis.

• Treatment is symptomatic, with a hard-soled shoe.

• Healing is usually uneventful.
• Zone 2 injuries are true Jones fractures.

• They result from adduction or inversion of the forefoot.

• The fracture is caused by tensile stress along the lateral border of the metatarsal.

• Treatment is controversial: advocates recommend both weight bearing and non–weight bearing in a short leg cast as well as ORIF.

Figure 64. Three zones of proximal fifth metatarsal fracture. Zone 1: avulsion fracture. Zone 2: fracture at the metaphyseal-diaphyseal junction. Zone 3: proximal shaft stress fracture. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

• Union is frequently a concern.

• Zone 3 injuries are now referred to as proximal diaphyseal stress fractures.

• These are relatively rare and seen mainly in athletes.

• They occur in the proximal 1.5 cm of the diaphyseal shaft of the metatarsal.

• Patients usually present with prodromal symptoms before complete fracture.

• This particular entity poses problems because of its tendency to nonunion.

• Initial treatment is between casted non weight bearing for up to 3 months and surgical intervention with grafting and internal compression.

• The remainder of the fifth metatarsal fractures not resulting from a direct blow have been termed dancer’s fractures.

• The usual pattern is a spiral, oblique fracture progressing from distal-lateral to proximal-medial.

• The mechanism of injury is a rotational force being applied to the foot while axially loaded in a plantar flexed position.

• Treatment is symptomatic, with a hard soled shoe.

Metatarsophalangeal Joints

• Mobility of the MTP joints is essential for forefoot comfort iormal gait; attempts should thus be made to salvage any motion at this level.

First Metatarsophalangeal Joint

EPIDEMIOLOGY

• Injuries to the first MTP joint are relatively common, especially in athletic activities or ballet.

• The incidence in US football and soccer has risen because of the use of artificial playing surfaces as well as lighter, more flexible shoes that permit enhanced motion at the MTP joint.

ANATOMY

• The MTP joint is composed of a cam-shaped metatarsal head and a matched concave articulation on the proximal phalanx. These contours contribute little to the overall stability of the joint.

• Ligamentous constraints includes dorsal capsule reinforced by the extensor hallucis longus tendon, plantar plate (capsular ligament) reinforced by the flexor hallucis longus tendon, flexor hallucis brevis tendon, and medial and lateral collateral ligaments.

• The plantar capsule is a thick, weight-bearing structure with strong attachments to the base of the proximal phalanx. There is a thinner, more flexible attachment to the plantar aspect of the metatarsal head proximally. Imbedded in this plantar structure are the two sesamoids.

MECHANISM OF INJURY

• Turf toe: This is a sprain of the first MTP joint. It reflects hyperextension injury to the first MTP joint as the ankle is in equinus causing temporary subluxation with stretching on plantar capsule and plate.

• In ballet dancers, injury may occur as a dancer falls over the maximally extended first MTP joint, injuring the dorsal capsule. Forced abduction may result in lateral capsular injury with possible avulsion from the base of the proximal phalanx.

• Dislocation of the first MTP joint is usually the result of high-energy trauma, such as a motor vehicle accident, in which forced hyperextension of the joint occurs with gross disruption of the plantar capsule and plate.

CLINICAL EVALUATION

• Patients typically present with pain, swelling, and tenderness of the first MTP joint.

• Pain may be reproduced with range of motion of the first MTP joint, especially at terminal dorsiflexion or plantar flexion.

• Chronic injuries may present with decreased range of motion.

• Most dislocations are dorsal with the proximal phalanx cocked up and displaced dorsally and proximally, producing a dorsal prominence and shortening of the toe.

RADIOGRAPHIC EVALUATION

• AP, lateral, and oblique views of the foot may demonstrate capsular avulsion or chronic degenerative changes indicative of longstanding injury.

CLASSIFICATION

Bowers and Martin

Grade I:	Strain at the proximal attachment of the volar plate from the first metatarsal head
Grade II:	Avulsion of the volar plate from the metatarsal head
Grade III:	Impaction injury to the dorsal surface of the metatarsal head with or without an avulsion or chip fracture

 

Jahss Classification of First Metatarsophalangeal Dislocations

This is based on the integrity of the sesamoid complex.

Type I:	Volar plate avulsed off the first metatarsal head, proximal phalanx displaced dorsally; intersesamoid ligament remaining intact and lying over the dorsum of the metatarsal head
Type IIA:	Rupture of the intersesamoid ligament
Type IIB:	Longitudinal fracture of either sesamoid

TREATMENT

• First MTP sprains
• Rest, ice, compression, and elevation (RICE) and nonsteroidal antiinflammatory medication are used.

• Protective taping with gradual return to activity is recommended; the patient may temporarily wear a hard-soled shoe with a rocker bottom for comfort.

• Pain usually subsides after 3 weeks of treatment, but an additional 3 weeks are usually necessary to regain strength and motion for return to competitive activity.

• Operative intervention is rarely indicated except in cases of intraarticular fractures or significant discrete instability. The presence of avulsion fragments and significant valgus instability may need to be addressed by ORIF or debridement and ligamentous repair.

• Displaced intraarticular fractures or osteochondral lesions should be fixed or debrided depending on their size.

• Dislocations
• Jahss Type I fracture: Closed reduction may be initially attempted. However, if irreducible by closed means, it will require open reduction.

• Jahss Type IIA, IIB fractures: These are easily reduced by closed means (longitudinal traction with or without hyperextension of the first MTP joint).

• After reduction, the patient should be placed in a short leg walking cast with a toe extension for 3 to 4 weeks to allow capsular healing.

• Displaced avulsion fractures of the base of the proximal phalanx should be fixed with either lag screws or a tension band technique. Small osteochondral fractures may be excised; larger fragments require reduction with Kirschner wires, compression screws, or headless screws.

COMPLICATIONS

• Hallux rigidus and degenerative arthritis complicate chronic injuries and may prevent return to competitive activity.

• Posttraumatic osteoarthritis: This may reflect chondral damage at the time of injury or may result from abnormal resultant laxity with subsequent degenerative changes.

• Recurrent dislocation: Uncommon, although it may occur in patients with connective tissue disorders.

Fractures and Dislocations of the Lesser Metatarsophalangeal Joints

Epidemiology

• Stubbing injuries are very common.

• The incidence is higher for the fifth MTP joint because its lateral position renders it more vulnerable to injury.

Anatomy

• Stability of the MTP joints is conferred by the articular congruity between the metatarsal head and the base of the proximal phalanx, the plantar capsule, the transverse metatarsal ligament, the flexor and extensor tendons, and the intervening lumbrical muscles.

Mechanism of Injury

• Dislocations are usually the result of low-energy stubbing injuries and are most commonly displaced dorsally.

• Avulsion or chip fractures may occur by the same mechanism.

• Comminuted intraarticular fractures may occur by direct trauma, usually from a heavy object dropped onto the dorsum of the foot.

Clinical Evaluation

• Patients typically present with pain, swelling, tenderness, and variable deformity of the involved digit.

• Dislocation of the MTP joint typically manifests as dorsal prominence of the base of the proximal phalanx.

Classification

DESCRIPTIVE

• Location
• Angulation
• Displacement
• Comminution
• Intraarticular involvement
• Presence of fracture-dislocation

Treatment

NONOPERATIVE

• Simple dislocations or nondisplaced fractures may be managed by gentle reduction with longitudinal traction and buddy taping for 4 weeks, with a rigid shoe orthosis to limit MTP joint motion, if necessary.

OPERATIVE

• Intraarticular fractures of the metatarsal head or the base of the proximal phalanx may be treated by excision of a small fragment, by benigeglect of severely comminuted fractures, or by ORIF with Kirschner wires or screw fixation for fractures with a large fragment.

Complications

• Posttraumatic arthritis: May result from articular incongruity or chondral damage at the time of injury.

• Recurrent subluxation: Uncommon and may be addressed by capsular imbrication, tendon transfer, cheilectomy, or osteotomy, if symptomatic.

Sesamoids

Epidemiology

• The incidence is highest with repetitive hyperextension at the MTP joints, such as in ballet dancers and runners.

• The medial sesamoid is more frequently fractured than the lateral owing to increased weight bearing on the medial side of the foot.

Anatomy

• The sesamoids are an integral part of the capsuloligamentous structure of the first MTP joint.

• They function within the joint complex as both shock absorbers and fulcrums in supporting the weight-bearing function of the first toe.

• Their position on either side of the flexor hallucis longus forms a bony tunnel to protect the tendon.

• Bipartite sesamoids are common (10% to 30% incidence in the general population) and must not be mistaken for acute fractures.

• They are bilateral in 85% of cases.

• They exhibit smooth, sclerotic, rounded borders.

• They do not show callus formation after 2 to 3 weeks of immobilization.

Mechanism of Injury

• Direct blows such as a fall from a height or a simple landing from a jump as in ballet can cause acute fracture.

• Acute fractures can also occur with hyperpronation and axial loading seen with joint dislocations.

• Repetitive loading from improper running usually gives rise to the more insidious stress fracture.

Clinical Evaluation

• Patients typically present with pain well localized on the plantar aspect of the “ball” of the foot.

• Local tenderness is present over the injured sesamoid, with accentuation of symptoms with passive extension or active flexion of the MTP joint.

Radiographic Evaluation

• AP, lateral, and oblique views of the forefoot are usually sufficient to demonstrate transverse fractures of the sesamoids.

• Occasionally, a tangential view of the sesamoids is necessary to visualize a small osteochondral or avulsion fracture.

• Technetium bone scanning or MRI may be used to identify stress fractures not apparent by plain radiography.

Classification

DESCRIPTIVE

• Transverse versus longitudinal
• Displacement
• Location: medial versus lateral

Treatment

• Nonoperative management should initially be attempted, with soft padding combined with a short leg walking cast for 4 weeks followed by a bunion last shoe with a metatarsal pad for 4 to 8 weeks.

• Sesamoidectomy is reserved for cases of failed conservative treatment. The patient is maintained postoperatively in a short leg walking cast for 3 to 4 weeks.

Complications

• Sesamoid excision may result in problems of hallux valgus (medial sesamoid excision) or transfer pain to the remaining sesamoid owing to overload.

Phalanges and Interphalangeal Joints

Epidemiology

• Phalangeal fractures are the most common injury to the forefoot.

• The proximal phalanx of the fifth toe is the most often involved.

Anatomy

• The first and fifth digits are in especially vulnerable positions for injury because they form the medial and lateral borders of the distal foot.

Mechanism of Injury

• A direct blow such as a heavy object dropped onto the foot usually causes a transverse or comminuted fracture.

• A stubbing injury is the result of axial loading with secondary varus or valgus force resulting in a spiral or oblique fracture pattern.

Clinical Evaluation

• Patients typically present with pain, swelling, and variable deformity of the affected digit.

• Tenderness can typically be elicited over the site of injury.

Radiographic Evaluation

• AP, lateral, and oblique views of the foot should be obtained.

• If possible, isolation of the digit of interest for the lateral radiograph may aid in visualization of the injury. Alternatively, the use of small dental radiographs placed between the toes has been described.

• Technetium bone scanning or MRI may aid in the diagnosis of stress fracture when the injury is not apparent on plain radiographs.

Classification

DESCRIPTIVE

• Location: proximal, middle, distal phalanx
• Angulation
• Displacement
• Comminution
• Intraarticular involvement
• Presence of fracture-dislocation

Treatment

• Nondisplaced fractures irrespective of articular involvement can be treated with a stiff-soled shoe and protected weight bearing with advancement as tolerated.

• Use of buddy taping between adjacent toes may provide pain relief and help to stabilize potentially unstable fracture patterns.

• Fractures with clinical deformity require reduction. Closed reduction is usually adequate and stable (Fig. 65).

• Operative reduction is reserved for those rare fractures with gross instability or persistent intraarticular discontinuity. This problem usually arises with an intraarticular fracture of the proximal phalanx of the great toe or multiple fractures of lesser toes.

• A grossly unstable fracture of the proximal phalanx of the first toe should be reduced and stabilized with percutaneous Kirschner wires or minifragment screws.

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Figure 65. A method of closed reduction for displaced proximal phalanx fractures. A hard object, such as a pencil, is placed in the adjacent web space and is used as a fulcrum for reduction. (From Bucholz RW, Heckman JD, Court-Brown C, et al., eds. Rockwood and Green’s Fractures in Adults, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2006.)

• Unstable intraarticular fractures of any joint despite adequate reduction should be reduced and percutaneously pinned in place to avoid late malalignment.

Complications

• Nonunion: Uncommon.
• Posttraumatic osteoarthritis: May complicate fractures with intraarticular injury, with resultant incongruity. It may be disabling if it involves the great toe.

Dislocation of the Interphalangeal Joint

• Usually due to an axial load applied at the terminal end of the digit.

• Most such injuries occur in the proximal joint, are dorsal in direction, and occur in exposed, unprotected toes.

• Closed reduction under digital block and longitudinal traction comprise the treatment of choice for these injuries.

• Once reduced, the interphalangeal joint is usually stable and can be adequately treated with buddy taping and progressive activity as tolerated.