Autologous cartilage as interpositional material for accelerating bone-tendon junction healing-a pilot histological study in rabbits

Based on findings from the authors' recent study which showed histologically an earlier tendon to articular cartilage structure incorporation than tendon to bone (BT) in a partial patellectomy model, the authors conducted a pilot study to explore the biological potential of using autologous cartilage as interpositional materials to reestablish a fibrocartilage BT junction zone and to accelerate the BT junction repair. Rabbits were used as experimental model and autologous fibrocartilage (autologous meniscus) and hyaline cartilage (articular cartilage) was used as interpositional materials for BT repair. Earlier and well incorporated BT interface was observed after using both fibrocartilage and hyaline cartilage to repair the BT junction compared with a direct BT reattachment at 8th postoperative week, without degenerative changes. The interpositional cartilage resembled the matrix of the normal fibrocartilage zone of the BT junction by evaluating its matrix proteoglycans using Safranin O staining. However, long-term histological observation and testing mechanical properties of the repaired BT junction via autologous cartilage as the interpositional materials for BT junction repair needs further study.