Stress Fracture of the Femoral Neck Following Total Knee Arthroplasty: A Case Series

A stress fracture of the femoral neck after total knee arthroplasty (TKA) is rare, with few reported cases in the English literature. We defined a stress fracture following TKA as a nontraumatic fracture developing in the femoral neck within six months of TKA. This retrospective case series highlights the predisposing factors, diagnostic challenges, and management of stress femoral neck fractures following TKA. In our series, the major risk factors for the fracture are an increase in the level of activity in osteoporotic bone after a period of relative immobility after TKA, steroid intake, and rheumatoid arthritis. Preoperative dual-energy X-ray absorptiometry (DEXA) screening may help in the early initiation of osteoporosis treatment as the majority of our cases come late in the knee arthritis stage and long after a period of relative inactivity. Timely diagnosis and management of a stress femur neck fracture in the early period may prevent fracture displacement, avascular necrosis, and nonunion.