Occult Acetabular Fracture Associated With Periprosthetic Femoral Fracture (Vancouver Type B3) Following Hemiarthroplasty in an Elderly Patient: A Case Report

With the increase in life expectancy, the number of elderly individuals undergoing hemiarthroplasty and total hip arthroplasty has risen, leading to a higher incidence of implant-related fractures. Diagnosing fractures, especially occult and non-displaced ones, can be challenging even with advanced imaging techniques. This report describes the diagnostic challenges and surgical management of a rare combination of periprosthetic femoral fracture and an ipsilateral acetabular occult non-displaced fracture. An 87-year-old woman with a history of left hemiarthroplasty experienced severe left hip pain after a fall and required an ambulance. Despite computed tomography evaluations, preoperative diagnosis of a left periprosthetic femoral fracture with stem loosening and ipsilateral acetabular occult non-displaced fractures was challenging. Intraoperatively, a non-displaced acetabular fracture with severe bone fragility was unexpectedly found. The surgical procedure involved inserting a revision femoral stem to bypass the fracture site and performing osteosynthesis for the acetabular fracture. Two years postoperatively, the patient's activities of daily living improved to the preoperative level. Periprosthetic femoral fractures combined with acetabular fractures can occur following hemiarthroplasty and total hip arthroplasty, presenting significant diagnostic challenges in preoperative imaging evaluations. Surgeons should always consider the possibility of acetabular fractures when planning revision total hip arthroplasty for periprosthetic femoral fractures and be prepared to address them appropriately.