^DEFINITION

^{Fractures of the femoral head are rare and occur almost exclusively with associated high-energy hip dislocations, where they may be seen in 5% to 15% of cases.}

^{Associated injuries to the femur, acetabulum, or acetabular labrum can affect treatment options.}

 

 

^ANATOMY

 

^{The spherical femoral head is almost completely covered by articular cartilage, which often is damaged during the hip dislocation.}

 

^{Blood is primarily supplied to the superior dome of the femoral head by the medial femoral circumflex artery, which travels around the posterior aspect of the proximal femur, traveling deep to the quadratus femoris and penetrating the joint capsule just inferior to the piriformis tendon (FIG 1).}

 

 

^{Additional vascular support is supplied by the lateral femoral circumflex artery and the foveal artery within the ligamentum teres.}

 

^{The anterior half of the femoral neck is devoid of vascular structures. Therefore, anterior surgical approaches to the hip joint do not compromise the vascular supply of the femoral head.}

 

^{The acetabular labrum increases the coverage of the femoral head but may be damaged during hip dislocation.}

 

^PATHOGENESIS

 

^{The fracture is a shearing injury as the femoral head strikes the acetabular rim. Injury to the articular cartilage of the femoral head is common with femoral head fractures, and posterior wall fractures also can occur with this injury.}

 

 

 

^{FIG 1 • The blood supply to the superior dome of the femoral head is primarily supplied by the medial femoral circumflex artery. It travels around the posterior aspect of the proximal femur, traveling deep to the quadratus femoris and penetrates the joint capsule just inferior to the piriformis tendon.}

 

 

^{Both the position of the leg at the time of impact and the patient's hip anatomy have been shown to play a role in the etiology of hip fracture-dislocations.}

 

^{Posterior dislocations, the most common type, occur when the hip is in a flexed, adducted, and internally rotated position.}

^{Decreased femoral anteroversion leads to reduced femoral head coverage by the acetabulum and increases the risk of hip dislocation.}

 

^{Anterior dislocations are less common. They occur when the hip is in an abducted and externally rotated position, which results in an impaction injury to the anterolateral femoral head (FIG 2).}

 

^{NATURAL HISTORY}

 

^{In an intermediate-term follow-up study by Jacob et al,3 despite open or closed treatment, only 40% of patients had satisfactory results after hip dislocation at an average of 4.5 years after injury. More than half of the patients had posttraumatic arthrosis.}

 

^{Osteonecrosis of the femoral head may develop in 20% of patients with femoral head fractures despite anatomic reduction.}

 

^{PATIENT HISTORY AND PHYSICAL FINDINGS}

 

^{Because of the high energy required to induce a fracturedislocation of the hip, all patients should undergo a thorough trauma evaluation for associated injuries.}

 

 

 

^{Airway, cardiovascular, head, and spine injuries should be stabilized emergently. Narcotic pain medication usually is required.}

 

 

 

^{FIG 2 • Anterolateral femoral head impaction injury following anterior hip dislocation.}

 

 

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^{FIG 3 • A. Prereduction AP radiograph demonstrating hip dislocation and femoral head fracture. B,C.}

^{Postreduction CT scans demonstrating femoral head fracture.}

 

 

^{Careful evaluation of the affected extremity is essential.}

 

^{The leg often appears shortened and internally rotated after a posterior hip dislocation.}

 

^{Suspicion for associated injuries, particularly around the knee, should remain high; such injuries can be recognized on physical examination.}

 

^{Injury to the knee ligaments or extensor mechanism is associated with traumatic hip dislocation and should be assessed with a knee stability examination.}

 

^{Because sciatic nerve injuries are common, motor and sensory examination of the affected extremity is critical, with particular attention paid to strength grades (1 to 5) and sensation in the peroneal and tibial nerve distribution.}

 

^{IMAGING AND OTHER DIAGNOSTIC STUDIES}

 

^{The hip fracture-dislocation is first evaluated on the trauma anteroposterior (AP) pelvis radiograph (FIG 3A). The goal should be to emergently reduce the hip, and further imaging should not excessively delay reduction of the dislocated hi}

 

^{Associated injuries such as femoral neck fractures, acetabular fractures, or pelvis fractures may require additional dedicated hip, Judet view, or pelvic inlet and outlet radiographs.}

 

^{A fine-cut computed tomography (CT) scan of the pelvis and femoral neck with coronal and sagittal reconstructions will further define the anatomy of the femoral head fracture and associated injuries (FIG 3B,C).}

 

 

^{This should be obtained after reduction of the hi A prereduction CT scan of the hip is not typically indicated.}

 

 

 

 

 

^{Although magnetic resonance imaging (MRI) can be used to evaluate femoral head osteonecrosis in follow-up care, acute imaging has not been demonstrated to be prognostic of this complication.}

 

DIFFERENTIAL DIAGNOSIS Femoral head fractures typically are classified according to Pipkin (Table 1). An isolated posterior wall fragment may be confused with a femoral head fracture.
	Table 1 Pipkin Classification of Femoral Head Fractures     Type Description Illustration     I Fracture inferior to the femoral head fovea

 

	Fracture superior to the femoral head fovea       Femoral head fracture plus femoral neck fracture       Femoral head fracture plus acetabular fracture

 

 

 

 

 

 

 

 

 

^{NONOPERATIVE MANAGEMENT}

 

^{Surgical management to reconstruct the femoral articular surface usually is indicated.}

 

^{Nonoperative management is used only in Pipkin type I fractures with small articular fragments with an associated concentric reduction of the hi}

 

 

^{No quality clinical studies are available to define the size of the fragment or amount of displacement that can be tolerated.}

^{The accepted guideline is that the fragment should be congruent with the intact femoral head.}

 

^{Small impaction injuries associated with anterior dislocation also may be treated nonoperatively in many cases.}

 

^{Patients managed nonoperatively should remain toe-touch weight bearing for 8 to 12 weeks. For posterior dislocations, hip flexion beyond 90 degrees should be avoided for 6 weeks to protect the posterior capsule.}

 

 

 

^{SURGICAL MANAGEMENT}

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^{Most patients with femoral head fractures require surgery to provide an anatomic reduction of the femoral}

^{head, remove osteochondral loose bodies, or obtain a concentric reduction of the hip joint. Loose body removal can delay the onset of arthrosis.}

 

^{Large, displaced fragments should be anatomically fixed.}

^{Smaller fragments inferior to the fovea can be excised if a quality, stable reduction of the fracture fragment cannot be obtained.}

 

^{Although their significance is unknown, labral tears often can be evaluated and treated surgically.}

 

^{Hip arthroplasty is another good treatment option in elderly patients, especially with large head fragments. Femoral head fractures in this age group tend to have a large amount of articular cartilage damage and impaction of the bone at the fracture line, which compromises the patient's outcome.}

 

^{Algorithm for surgical management}

 

 

^{Nondisplaced fracture or small impaction injury}

 

 

 

^{Nonoperative treatment Displaced fragment}

 

 

 

^{Small: surgical excision Large: surgical fixation Elderly patient}

 

 

^{Small fragment without evidence of femoral head impaction: surgical excision Large fragment or significant femoral head impaction: hip arthroplasty}

 

^{Preoperative Planning}

 

^{If the hip is dislocated, it should be emergently reduced under general anesthesia with skeletal relaxation.}

 

 

^{Inadequate anesthesia during hip reduction can lead to further damage to the femoral head, femoral neck, or acetabulum as the hip is relocated.}

 

^{If the hip is reduced, the patient should be placed in 30 pounds of longitudinal skeletal traction until formal open reduction and internal fixation of the femoral head occurs. Traction will unload the femoral head and prevent ongoing third-body wear within the hip joint.}

 

 

^{Repeat radiographs and a postreduction CT scan should be obtained to confirm reduction of the hip and evaluate for loose bodies or fracture morphology.}

 

^{It is reasonable at this point to delay definitive surgery until the appropriate surgeon, anesthesiologist, and equipment are available.}

 

^{If the hip is irreducible, or there is an associated femoral neck fracture, emergent open reduction and internal fixation is required.}

 

^Approach

 

^{The most difficult decision is determination of the best operative approach.}

 

 

^{Epstein et al1 originally argued that all femoral head fractures should be approached posteriorly because the posterior blood supply to the femoral head had already been damaged during hip dislocation. This left the anterior capsular blood supply intact.}

 

^{However, the anterior capsule and anterior femoral neck provide very little vascular supply to the femoral head. In addition, visualization of the anteriorly located femoral head fracture is often inadequate.}

 

^{This approach is best when large femoral head fragments remain dislocated posteriorly after reduction of the hip or with an associated posterior column or posterior wall fracture.}

 

 

^{However, visualization of the anterior head fragment is difficult through a posterior approach and such a fracture may be better treated with a Ganz surgical dislocation.}

 

 

^{Swiontkowski et al4 effectively demonstrated that better visualization of the femoral head was obtained for most Pipkin I and II femoral head fractures by using the distal limb of an anterior Smith-Petersen approach.}

 

 

^{Lower rates of osteonecrosis were seen, although a slightly higher risk of heterotopic ossification was observed.}

 

^{A Smith-Petersen approach is currently the most commonly used method for fixation and is the preferred approach for excision of the fragment.}

 

^{Alternatively, better visualization of both the femoral head and the fracture fragment can be obtained through a surgical hip dislocation, as described by Ganz et al.2}

 

^{This approach safely preserves the medial circumflex arterial supply to the femoral head.}

 

^{It also allows the best access to associated injuries such as posterior acetabular fractures, labral tears, osteochondral debris, or posteriorly dislocated femoral head fragments.}

 

^{Surgical dislocation also provides improved access to angulate lag screw fixation perpendicular to the femoral head fracture line.}

 

^Positioning

 

^{For an anterior Smith-Petersen approach, the patient is positioned supine on a radiolucent table with a hip bump and the affected leg draped free.}

 

^{For a posterior Kocher-Langenbeck approach, the patient is placed prone or lateral on a radiolucent fracture table with the knee flexed to 90 degrees to relieve sciatic nerve tension.}

^{Consider using traction.}

 

^{For a Ganz surgical dislocation, the patient is placed on a radiolucent table with a beanbag in the lateral decubitus position and the affected leg draped free.}

 

 

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^TECHNIQUES

• ^{Smith-Petersen Anterior Approach}

^{Incision and Dissection}

^{The patient is positioned supine on a radiolucent table with the leg draped free.}

^{A vertical incision is made from the anterior superior iliac spine extending distally toward the lateral border of the patella (TECH FIG 1A).}

^{The sartorius and tensor fascia lata are identified (TECH FIG 1B). The fascia is incised over the medial aspect of the tensor muscle, and the medial border of the tensor muscle is followed to develop the}

 

^{interval between the tensor and sartorius muscles (TECH FIG 1C).}

 

^{The tensor muscle is retracted laterally and the sartorius muscle medially.}

 

^{Find the lateral femoral circumflex vessel traversing the inferior part of the wound as this marks the distal aspect of the incision. Do not cut or ligate this vessel as that may impair blood supply to the femoral head.}

 

 

 

^{TECH FIG 1 • Smith-Petersen anterior approach. A. Incision starts from the anterior superior iliac spine extending distally toward the lateral border of the patella. B. The fascia is incised over the medial border of the tensor muscle. C. The medial border of the tensor muscle is followed to develop the interval between the tensor muscle and the sartorius muscle. (continued)}

 

 

^{The direct and indirect heads of the rectus femoris muscle are identified and are retracted medially (TECH FIG 1D). There is an overlying fascial layer that must be divided to be able to see this muscle.}

 

^{In most patients, a residual muscle belly, the iliocapsularis muscle, is deep to the rectus muscle (TECH FIG 1E). This muscle is swept medially, exposing the capsule.}

 

^{Place a retractor over the anterior wall of the acetabulum to improve visualization.}

 

^{If additional exposure is necessary, a portion of the direct head of the rectus muscle may be released and repaired at the end of the case.}

^Capsulotomy

 

^{A longitudinal incision is made from the base of the femoral neck along the axis of the femoral neck and extended until reaching the intact acetabular labrum. Medially, a capsular incision is made along both the acetabular rim and the base of the femoral neck (TECH FIG 2A). Laterally, only a capsular incision}

 

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^{along the articular rim is made to protect the femoral head blood supply at the posterior base of the femoral neck.}

 

 

 

 

^{TECH FIG 1 • (continued) D. The direct and indirect heads of the rectus femoris muscle are identified and retracted medially. E. The iliocapsularis muscle lies deep to the rectus muscle. This muscle is swept medially to expose the joint capsule.}

 

 

^{Tag sutures are placed at the corners of the “T” in the capsule near the acetabular labrum to assist with capsular retraction.}

 

^{Blunt retractors are placed within the joint capsule to obtain good exposure of the femoral head fracture (TECH FIG 2B).}

 

^{External rotation of the leg and hip flexion will improve fracture visualization.}

 

 

 

^{TECH FIG 2 • Smith-Petersen anterior approach. A. A capsulotomy is performed by making a longitudinal incision from the base of the femoral neck to the articular rim along the axis of the femoral neck. Medially, a capsular incision is made along both the acetabular rim and the base of the femoral neck. Laterally, only a capsular incision is made along the articular rim. B. After the capsulotomy is performed, blunt retractors are placed around the femoral neck to expose the femoral head and neck.}

 

^{Fracture Reduction and Fixation}

 

^{Distract, lavage, and carefully inspect the joint to remove any loose bodies.}

 

^{Visualization may be improved by cutting the ligamentum teres.}

 

^{In some cases, complete anterior dislocation of the femoral head will facilitate fracture reduction and insertion of definitive fixation.}

 

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^{The fragment is excised if too small for internal fixation.}

 

^{A pointed reduction clamp or dental pick is used to reduce the displaced fragment.}

 

^{Many fractures have a component of impaction injury on the femoral head, so the fracture may not key in circumferentially. Circumferential visualization of the fracture is necessary to confirm that adequate reduction has been obtained.}

 

^{The fracture is fixed with countersunk 3.5- or 2.7-mm lag screws or headless self-compressing screws (eg, Acutrak [Acumed LLC, Hillsboro, OR] or Herbert-Whipple screws [Zimmer Inc., Warsaw, IN]).}

 

 

^{It is important to ascertain that the screw heads are recessed within the bone. Loosely repair the capsule at the completion of the case.}

• ^{Ganz Surgical Dislocation}

   

  ^{The patient is in the lateral position.}

   

  ^{Either a direct lateral incision or a traditional posterolateral approach is used.}

   

  ^{Anterior to the trochanter, the gluteus maximus is retracted posteriorly and the tensor fascia lata.}

   

  ^{Posterior to the trochanter, the interval between the gluteus minimus and the piriformis is identified. The gluteus minimus is sharply elevated anteriorly, and the piriformis is left intact.}

   

   

   

  ^{TECH FIG 3 • Ganz surgical dislocation. A. The trochanteric osteotomy is made parallel to the shaft of the femur. B. Z-shaped capsulotomy. C-E. Intraoperative views following surgical dislocation of the hi The ligamentum teres was transected to improve exposure, but the medial retinaculum was left intact. The fragment is fixed with three headless screws. Note the area of femoral head bone loss due to impaction. F,G. Posterosuperior labral tear is demonstrated. The labrum is reduced and secured with suture anchors. Surgical dislocation provides the best exposure of the acetabulum and is our preferred exposure for this fracture pattern. H. Postoperative radiograph. The trochanteric fragment is stabilized with two or three 3.5-mm cortical screws directed in a cephalad to caudad direction. (continued)}

   

   

  ^{The dissection is kept superior to the piriformis muscle because the medial femoral circumflex vessel penetrates the hip capsule at the inferior margin of the piriformis.}

   

  ^{The trochanter is osteotomized, leaving the piriformis and a portion of the tip of the trochanter intact to protect the medial femoral circumflex vessel. The osteotomy is oriented parallel to the shaft of the femur (TECH FIG 3A).}

   

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  ^{TECH FIG 3 • (continued)}

   

   

  ^{The gluteus minimus, gluteus medius, the trochanteric fragment, the vastus lateralis, and the vastus intermedius muscles are sharply elevated anteriorly.}

   

  ^{Placing the leg in the figure-4 position with the operative-side foot on the table improves exposure of the anterior capsule.}

   

  ^{A Z-shaped capsulotomy is performed with the cephalad limb posteriorly and the caudal limb anteriorly (TECH FIG 3B). Place tag sutures at the corners of the capsulotomy to improve visualization and for later repair.}

   

  ^{The femoral head is dislocated anteriorly.}

   

  ^{The femoral head fragment is reduced or excised.}

   

  ^{The labrum is assessed and is fixed with suture anchors if it is torn (TECH FIG 3C-H).}

   

  ^{If an associated posterior wall fragment is present, the hip is reduced and the wall fragment repaired in standard fashion.}

   

  ^{The capsule is loosely repaired, and the trochanter is reattached with two or three 3.5-mm cortical screws.}

   

  ^{PEARLS AND PITFALLS}

  ^Associated

  ^injuries

  • ^{Associated fractures of the femoral neck and acetabulum are common. Review}

  ^{the initial injury films and post-hip reduction CT scan carefully. Select an appropriate surgical approach.}

  ^{Sciatic nerve ▪ Subtle injuries are common after hip dislocation. Careful preoperative motor}

  ^{dysfunction examination will find such dysfunction is a result of the injury, not of surgery. Careful protection and retraction of the nerve is essential during posterior or surgical dislocation approaches.}

   

   

  ^Malreduction

• ^{This is a shearing injury that results in a femoral head fracture, articular cartilage damage, and impaction injury to the femoral head. It can be difficult to obtain a circumferential anatomic reduction because of the impaction injury. Circumferential visualization of the fracture is necessary to avoid a large articular step-off. The tendency is to malreduce the posterior aspect of the fracture owing to poor exposure and incomplete visualization of the fracture.}

   

  ^{Screw length and type}

  • ^{Ensure that the screws do not penetrate into the joint. They should be recessed beneath the cortex of the femoral head. Use headless screws rather than standard screws because the head of the standard screw will displace the borders of the thin fracture fragment as the head engages the bone.}

     

    ^{Femoral head vascular supply}

    • ^{Drilling the superior surface of the femoral head with a 2.0-mm drill bit should produce arterial bleeding if the vascular supply to the femoral head has been maintained.}

 

^{POSTOPERATIVE CARE}

 

^{Patients are given 24 hours of appropriate antibiotic prophylaxis.}

^{Deep venous thrombosis prophylaxis is started 24 hours postoperatively and is used before surgery if it has been delayed for more than 24 hours after injury.}

^{Heterotopic ossification prophylaxis using either 700 cGy of radiation or indomethacin 25 mg three times daily is considered in patients with significant damage to the gluteus minimus or rectus femoris muscles.}

^{Patients are allowed 30 to 40 pounds weight bearing for 8 to 12 weeks, then progressed to full weight bearing as tolerated. Hip flexion is limited to 90 degrees for 6 weeks.}

^{Pool therapy is started once the incision is dry and the sutures are removed.}

^{Once weight bearing is initiated at 12 weeks, more aggressive physical therapy focusing on gait training and quadriceps and hip abductor strengthening is started.}

^OUTCOMES

^{Because of the rarity of femoral head fracture-dislocations, no large prospective trials have compared surgical versus nonsurgical treatment methods.}

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^{Most retrospective reviews, including those by both Epstein et al1 and Jacob et al,3 report less than 50% good or excellent results at 5 to 10 years of follow-u}

^{Posttraumatic arthrosis is common following a femoral head fracture, and patients should be warned early of the poor prognosis.}

 

^{COMPLICATIONS}

^{Posttraumatic arthrosis: greater than 50% Femoral head osteonecrosis: 20%}

^{Neurologic injury: 10% (60% of these recover some function)}

^{Lateral femoral cutaneous nerve injury after Smith-Petersen approaches Heterotopic ossification: 25% to 65%; higher risk with anterior approach Hip instability}

^{Deep venous thrombosis}

 

 

^REFERENCES

1. ^{Epstein HC, Wiss DA, Cozen L. Posterior fracture dislocation of the hip with fracture of the femoral head. Clin Orthop Relat Res 1985; 201:9-17.}

    

    

2. ^{Ganz R, Gill TJ, Gautier E, et al. Surgical dislocation of the adult hip a technique with full access to the femoral head and acetabulum without risk of avascular necrosis. J Bone Joint Surg Br 2001;83(8):1119-1124.}

    

    

3. ^{Jacob JR, Rao JP, Ciccarelli C. Traumatic dislocation and fracture dislocation of the hi A long-term follow-up study. Clin Orthop Relat Res 1987;214:249-263.}

    

    

4. ^{Swiontkowski MF, Thorpe M, Seiler JG, et al. Operative management of displaced femoral head fractures: case matched comparison of anterior versus posterior approaches for Pipkin I and Pipkin II fractures. J Orthop Trauma 1992;6:437-442.}