Articular cartilage restoration with costal cartilage previously fused with bone.

A novel procedure was developed for restoration of an articular cartilage defect using an autologous costal cartilage prepared with iliac bone, and the durability in vivo of this biologic construct was examined. First, an osteochondral complex was prepared (successful preparation, 67 of 80). Cancellous bone blocks isolated from the ilium of male Japanese White rabbits aged 5 months were implanted onto the surface of the costal cartilage before being tied by a pair of 3-0 silk thread sutures that were looped around the costal cartilage from behind. Second, 3 months later, the bone-attached costal cartilage was harvested and implanted into a full-thickness cartilage defect induced in a trochlear groove of the femur. All of the grafts were fixed to the recipient, maintaining its cartilage structure until 6 months (n = 28) and 12 months (n = 12) after implantation. However, when the costal cartilage without any bony portion was implanted into a similarly induced defect, 42% (10 of 24) were detached from the recipient before 12 months after implantation. The nontreated defect did not heal spontaneously to a satisfactory level (n = 12). These findings suggest that an osteochondral fragment, prepared by grafting cancellous bone onto costal cartilage, can be used for articular cartilage restoration.