HISTORY: A 59-year-old beach volleyball player sustained a hip injury during a match. While playing, he landed on soft sand from a jump on his right leg. He felt a ‘jolt and pop’ in his right hip that radiated to his deep thigh, and felt his leg seemed ‘locked out of place.’ No past history of hip dysplasia, dislocation, hip surgery. He asked someone to pull on his leg to try and improve symptoms. After the incident, he was able to walk off on his own power, but noted discomfort upon weight bearing and walking.
PHYSICAL EXAMINATION: Examination revealed no focal tenderness, full ROM of the hip, but had discomfort with FABER maneuver. He was able to walk around at the clinic without assistance.
DIFFERENTIAL DIAGNOSIS: Hip dislocation, Acetabular labral tear, λoose body, Coxa saltans, Occult fracture
TEST AND RESULTS: X-rays were obtained and suggested a posterior rim acetabular fracture; Same-day CT showed a comminuted intra-articular posterosuperior acetabular wall fracture with effusion, femoral head impaction, and irregularity of the central fovea suggested ligamentum teres femoris avulsion
FINAL WORKING DIAGNOSIS:Right posterior wall acetabulum fracture with femoral head impaction
TREATMENT AND OUTCOMES: 1. Referred to Orthopedic Trauma; surgeon recommended evaluation under anesthesia (EUA) due to possibility of transient hip dislocation to evaluate for instability, which he declined. Recommended toe-touch weightbearing with crutches which he also declined as he felt able to ambulate. Hip dislocation precautions given.
2. At 1 month, he ended up using two canes to walk but was able to without significant symptoms. Advanced to weightbearing as tolerated.
3. At 3 months, felt better but still unable to play volleyball or run. X-rays showed interval healing in unchanged alignment.
Case reports unusual etiology of a posterior wall fracture after seemingly ‘minor’ injury on soft sand, and providers should have a low threshold to proceed with further workup such as CT. Unknown if bystander pulling on leg worsened injury. May even had transient hip dislocation, a rare injury due inherently stable hip bony anatomy. Case raises awareness to counsel patient on recurrent dislocation, osteonecrosis, and arthritis risks with these injuries, and consider bone density testing if a low-energy injury.