Review Question - QID 219605

This 34-year-old male sustained a high-energy posterior hip fracture-dislocation with post-reduction CT imaging demonstrating an intra-articular fragment. The most appropriate treatment includes surgical hip dislocation through the posterior Kocher-Langenback approach (Answer 5).

Native hip dislocations are rare, high-energy injuries most commonly seen in younger patients. A high rate of concomitant injuries exist, which most often involves the posterior wall of the acetabulum, but not uncommonly involving the pelvis, femur, or knee. Prompt reduction of the dislocation within six hours of dislocation is of paramount importance to reduce the risk for femoral head avascular necrosis. Post-reduction CT imaging is required to evaluate for intra-articular fragments or medial joint space widening, with persistent widening suggesting soft tissue (labrum) interposition and ultimately malreduction of the hip. When present, open reduction via anterior or posterior approaches is most necessary, with the former most appropriate for anterior dislocations, and the latter most appropriate for posterior dislocations, though a trend towards arthroscopic/percutaneous techniques in select patients has been emerging over the recent years.

Marecek and Routt describe a percutaneous technique for removing intra-articular bodies within the "dome" of the hip joint following traumatic femoral head or acetabular fracture-dislocations. The technique involves making a lateral incision at the level of the acetabular dome, gaining access through the capsular disruption sustained during hip dislocation to facilitate removal. The authors report the successful removal of debris with the technique on three patients.

Nepple et al. provide a case report on a 12-year-old male who sustained a remote hip injury two months prior while water skiing, now presenting with hip pain. MRI was obtained four weeks after the injury, which showed osteochondral fragments within the joint, posterior acetabular wall lip fracture, and ligamentum teres rupture, while CT demonstrated an osteochondral joint fragment and increased medial joint space, all of which suggested a hip dislocation at the time of injury. The patient underwent diagnostic hip arthroscopy followed by surgical hip dislocation utilizing a trochanteric osteotomy for definitive treatment of his injuries, which resulted in excellent outcomes (no pain, full range of motion) at two years postoperatively.

Figures A & B demonstrate a native right posterior hip dislocation with posterior wall comminution. Figure C shows post-reduction axial CT imaging demonstrating an incarcerated bony fragment. Illustrations A & B demonstrate postoperative films following the removal of the incarcerated fragment and fixation of the comminuted posterior wall.

Incorrect answers:
Answers 1 and 2: the anterior and anterolateral approaches to the hip are accepted approaches for anterior hip dislocations, not posterior.
Answer 3: the medial approach to the hip is more commonly utilized for pediatric patients with congenital hip dislocations
Answer 4: the lateral approach is not routinely used for hip dislocations.