The longest delay between femoral neck fracture and femoral head collapse?

Osteonecrosis and acute collapse of the femoral head occurred in a 79-year-old woman with a history of femoral neck fracture sustained 28 years previously. The occurrence of radiographic signs and clinical symptoms was associated with new functional demands on the hip because of a recent contralateral hip fracture. The femoral head collapse necessitated total hip arthroplasty. Determination of femoral head vitality at the time of arthroplasty implicated partial avascularity of the head as a cause of the collapse. With high probability, this partial avascularity was induced by the femoral neck fracture sustained 28 years earlier.