Survivorship and radiographic analysis of knee osteoarticular allografts

An evaluation of long-term survival and radiographic deterioration of 118 knee osteoarticular allografts in 114 patients was performed. Radiographic analysis was done according to the Musculoskeletal Tumor Society grading system. A failure was defined as when the allograft was removed during a revision procedure or amputation. Ten patients were lost to followup during the first 2 years after surgery. Eighteen patients without allograft failures died of complications related to the tumor. Twenty-six allografts failed because of infection (13 allografts), local recurrence (eight allografts), massive resorptions (three allografts) and fractures (two allografts). Sixty-four allografts still were in place at a mean of 98 months (range, 36-360 months) after implantation. The Kaplan-Meier 5-year survival rate for the knee osteoarticular allografts was 73% and the limb preservation rate was 93%. The mean radiographic score was 83%. Sixty-four percent of the allografts showed no radiologic changes or minor articular deterioration. Fourteen percent had narrowing of the joint space of more than 2 mm, and 22% had some form of subchondral bone collapse. Five patients required joint resurfacing to preserve the original allograft. Most of the allograft failures occurred during the first 4 years, and the allograft survival rate for the current series remained unchanged after 5 years.