Posterior hip dislocation associated with concomitant ipsilateral femoral head and shaft fractures: an unusual combination of injuries

Abstract

The combination of posterior hip dislocation with an ipsilateral femoral head and shaft fractures is unusual. While cases of concomitant fractures of femoral head and shaft have been previously reported, the treatment of such injuries is challenging. Presence of an associated hip dislocation further complicates the matter. A timely diagnosis and treatment are crucial to have a good outcome.

We are presenting the case of a 20-year-old man who sustained a traumatic posterior hip dislocation with ipsilateral femoral shaft and femur head fractures. After reducing the hip, we fixed the femoral shaft with a retrograde femur nail and the femoral head by the trochanteric flip approach in the same sitting. The patient returned to his pre-injury occupation after 4 months. He has been doing well until his last follow-up, 1 year after the surgery, thus emphasising the utility of following basic principles of trauma management in the management of unusual injuries.

Background

Hip dislocation usually results from high-energy trauma.^{1 2} Traumatic posterior dislocation of the hip with a concomitant ipsilateral femoral shaft and head fracture without any acetabular fracture is extremely unusual. The diagnosis and treatment of this type of injury pose a challenge to the treating orthopaedic surgeon. The management decision is difficult in such cases due to the scarcity of published data. While a surgeon may plan a treatment involving a reduction of the dislocation and a fixation of the femoral head and the shaft fractures, the sequence in which the surgery should proceed is not clear. This stems from the fact that only two such cases have been described previously in the published English-language literature.^{3 4} However, in none of them the actual outcome of the patient after treatment has been presented. While in one of them, the patient died 2 days after the surgery, in the other the patient was lost to follow-up. Based on the recent evidence, we believe that an early hip reduction and fixation of the femoral head fragments to ensure congruity of the articular surface of the head is the key to prevent serious complications like avascular necrosis and secondary osteoarthritis.^{5 6} We are here reporting such a case in a young man. We informed the patient that the details related to his treatment would be submitted for publication and he consented for the same.

Case presentation

A 20-year-old man presented to the emergency department of our hospital 3 hours after being involved in a high-velocity road traffic accident. The patient had severe pain and deformity of his left lower limb. On clinical examination, the left lower limb was in an attitude of flexion and external rotation. The femoral pulse was feeble. There was significant swelling and bruising over the mid-thigh and gluteal regions. Tenderness and abnormal mobility were present along the thigh. The distal pulses were well palpable, and he had no neurological deficits. There were no abrasions or lacerations anywhere and he was not bleeding from any site.

Investigations

After providing first aid and ensuring haemodynamic stability, he was taken for radiographs which showed a posterior hip dislocation with a femoral head fracture that was classified as a modified Pipkin type I⁷ fracture and a femoral shaft fracture (figure 1). CT images in axial plane and three-dimensional reformatting were obtained to rule out any associated femoral neck or acetabulum fracture (figure 2).

Figure 1.

Preoperative anteroposterior (A) and lateral (B) radiographs of the left hip with femur showing the hip dislocation with the femoral head and shaft fractures.

Figure 2.

CT scan images in the coronal plane (A) and three-dimensional reconstruction of the pelvis (B) showing the posterior dislocation of the hip with a fracture of the femur head.

Treatment

We attempted a closed reduction of the hip in the emergency room under midazolam sedation with gentle traction and manipulation, but it failed. Following this, he was taken to the operating room 2 hours after presentation with an aim to reduce the dislocation, and fix the fractures of the femoral head and shaft.

General anaesthesia was used for induction, and we could achieve a closed reduction of the dislocated hip with the aid of a 5 mm Schanz screw placed at the greater trochanter. We applied a laterally directed traction with the Schanz screw in addition to the linear traction applied in line with the femoral shaft for obtaining the closed reduction of the hip dislocation. Next, an open reduction and internal fixation of femoral shaft fracture were performed with the patient positioned in a supine position and using a retrograde femur nail for stabilisation. We repositioned the patient onto a right lateral position for addressing the femoral head fracture. Femur head fragments were accessed via a trochanteric flip osteotomy followed by a safe surgical dislocation using the technique described by Ganz et al.⁸ The femoral head fracture was visualised, and reduction was performed. Once the reduction was judged to be anatomical, fixation with three headless screws was done (figure 3). The joint was cleaned and irrigated with normal saline to remove any debris. Femur head was relocated, and capsular closure was done. We then confirmed the reduction to be concentric under image intensifier. The trochanteric osteotomy was fixed with three cortical screws. Postoperatively, an upper tibial pin traction was applied for 2 weeks. Indomethacin 75 mg once a day was started and continued for 6 weeks. Low molecular weight heparin injection was used for thromboprophylaxis. From the first postoperative day, isometric quadriceps exercises were started. After 2 weeks, we removed the skeletal traction and allowed the patient to sit on the side of the bed and perform knee movements. Quadriceps strengthening exercises were started and non-weight-bearing ambulation with a walker was also started after 2 weeks of surgery. We discharged him to his home with an advice for regular and timely follow-up.

Figure 3.

Intraoperative pictures of the femoral head fracture, before (A) and after (B) the reduction and fixation with headless screws. Intraoperative image intensifier image (C) after fixation of the trochanteric flip fragment.

Outcome and follow-up

Six weeks after the surgery, radiographs were obtained which showed maintained reduction of both the hip dislocation and the femoral fractures (figure 4). We allowed partial weight-bearing ambulation from 6 weeks onwards. At the end of 3 months, the patient managed to bear full weight without any pain but had some limp. He went back to his workplace at the end of 4 months. He was then followed up at 6 months and 1 year after the surgery. At his latest follow-up visit, he was pain free, had no limp and his hip was stable. The radiographs showed abundant callus across the femoral shaft fracture site suggestive of secondary healing. The femoral head fracture and the trochanteric osteotomy sites were united. No radiological signs of avascular necrosis of the femoral head or osteoarthritis were appreciable (figure 5). Harris hip score was 88.9 at the end of 1 year.

Figure 4.

Postoperative radiographs at 6 weeks showing congruent reduction of the femoral head (A, B) and retrograde nail of the left femur shaft fracture (C, D).

Figure 5.

One-year postoperative radiographs showing no signs of osteonecrosis of the femoral head or post-traumatic osteoarthritis (A, B). Anteroposterior (C) and lateral (D) radiographs of the femoral shaft fracture.

Discussion

Depending on the mechanism of the trauma, and the position of the knee at the time of impact, various patterns of injuries around the hip can be seen especially in individuals who have been involved in high-velocity road traffic accidents. Hip dislocation with isolated femoral head, neck, trochanter, shaft or acetabular fractures are not very uncommon injuries.^9–13 The occurrence of combined injuries can often be explained by the application of different forces such that the hip first undergoes a dislocation followed by a direct trauma to the femoral shaft resulting in a femoral fracture.¹⁴ However, hip dislocation in combination with fractures of both the femoral head and shaft on the same limb is extremely rare. In the absence of adequate suspicion and imaging studies, the diagnosis can be missed or can get delayed in such cases. The associated complications related to late diagnosis or treatment like avascular necrosis and secondary osteoarthritis can be the causes of significant morbidity.

After a search of the English-language literature for similar cases, we could retrieve the details of only two similar cases. In such a case, Galois et al⁴ too had attempted a closed reduction of hip but failed to achieve it. They reduced the hip joint surgically and neglected the femoral head fragment while performing an intramedullary nailing for the femoral shaft fracture. Unfortunately, they could not evaluate the outcome as the patient died 2 days after the surgery. Alhammoud et al³ performed a closed reduction of the hip after applying a temporary external fixator for the shaft fracture. A fixation of the head fragment was not performed. Subsequently, they exchanged the external fixator for an intramedullary nail. In this case too, the outcome was not reported as the patient was lost to follow-up.

Closed reduction of hip is technically challenging and often difficult when the ipsilateral femoral shaft is also fractured. In these cases, closed reduction by simple traction and manipulation has been reported to be successful in less than 50% of cases.^{15 16} Various authors have used different traction aids to facilitate a closed reduction of the hip before fixing the femoral shaft fracture. Manipulation using an external fixator for the femoral shaft, intramedullary Denness device, traction screw into the femoral neck (Smith screw), Steinmann pin, Lardennois hoop apparatus and traction bow have been used with varying degrees of success.3 14 17–19 In our case, we performed a closed reduction of the hip by manipulation and applying a laterally directed traction using a Schanz screw inserted into the greater trochanter.

As evidence is emerging in favour of surgical management over conservative treatment of Pipkin type I (infrafoveal) femoral head fractures,²⁰ we opted for an operative intervention in our case. However, controversy exists on whether fragments should be excised or fixed internally.^21–23 Yoon et al⁷ found better clinical outcomes with an internal fixation of large infrafoveal fragments in comparison with surgical excision. They concluded that surgical excision should be performed only when the fragment is very small and distal to fovea centralis. Trochanteric flip approach was found to be superior in terms of wide exposure and has less likelihood of resulting avascular necrosis in comparison with the conventional posterior (Kocher-Langenbeck) approach.²⁴ Due to the large infrafoveal femoral head fragment in our case, we opted to proceed with the fixation with headless compression screws after safely dislocating the femoral head.

Although piriformis entry nails have been reported to result in only a minimal reduction in femoral head perfusion and damage to the retinacular vessels,²⁵ in conditions where the femoral head blood supply is already jeopardised by the hip fracture dislocation, the use of piriformis nail could be questionable. Moreover, fixation of the trochanteric fragment might also become difficult if a piriformis or trochanteric entry nail is performed along with a trochanteric flip osteotomy. Taking these things into consideration, we opted for a retrograde nail over an antegrade one.

Oransky et al²⁶ reported the rate of heterotopic ossification (HO) to be 80% in their study on femoral head fractures. HO is a debilitating condition resulting in significant restriction of movements. Injury to the muscles from the initial trauma and tissue handling during surgery has been reported to be a contributory factor for its development. There is no consensus on the method to prevent its development with many studies not supporting the role of non-steroidal anti-inflammatory drugs. However, we routinely use indomethacin for prophylaxis in adults undergoing surgeries for acetabular fractures.

While we used skeletal traction in the initial 2 weeks intending to prevent pain arising from the fixation sites of the femoral head fracture and the trochanteric osteotomy, in retrospect we believe that this could have been avoided as the patient had only minimal pain from the fourth postoperative day.

In conclusion, while the management of the three injuries—hip dislocation, femoral head fracture and femoral shaft fracture—may appear to be straightforward, our intention for reporting this case is to make the orthopaedic surgeons aware of the possibility of this combination of injuries and to the fact that irrespective of the severity, sticking to the basics of fracture management is essential. While further observation is necessary in our patient to identify if he develops any complication like avascular necrosis of femoral head or secondary osteoarthritis, we do believe that standard practices of fracture management must be followed for obtaining a good outcome.

Learning points.

• A posterior dislocation of femoral head with concomitant ipsilateral femoral head and shaft fractures is an unusual injury.

• Lateral traction through a Schanz screw can result in a successful reduction of a dislocated hip in cases where the femoral shaft is also fractured.

• After a closed reduction of the hip, a retrograde nailing of the femoral shaft fracture followed by a fixation of the femoral head fracture using the safe surgical dislocation technique, though challenging, is probably a safer method to obtain good functional and radiological outcomes in such an injury.

Ethics statements

Patient consent for publication

Obtained.