Long-term follow-up of patients with osteochondral allografts. A correlation between immunologic responses and clinical outcome.

This article confirms immunologic responses in humans to histocompatibility antigens (Class I and II) presented by frozen osteochondral allografts. These observations include a correlation of immune responses with long-term clinical outcome. As found in animal models, matching of histocompatibility antigens, particularly to Class II, improves clinical and, presumably, biologic success following implantation of massive frozen bone allografts in humans. The presence of sensitization clearly does not preclude a satisfactory outcome, nor have other reconstructive alternatives (e.g., metallic implants) been shown to be superior in their long-term results.