Viability of loose body fragments in osteochondritis dissecans of the knee. A series of cases.

The purpose of this study was to determine if the cartilage from loose osteochondral fragments remains viable. Five patients with OCD of the knee who had undergone surgical treatment (arthroscopic reduction and internal fixation of the loose body) were included. The average age of patients was 13 years (range 10-14 years). Cartilage samples were obtained from the loose body fragments before reattachment was performed (study group) and from the healthy native cartilage (intercondyle area, control group) from each of the five patients. Tissue viability was assessed using live-dead assay in both groups. All five loose osteochondral fragments showed similar viability to the healthy native cartilage group, with 88% cell viability (95% CI 50-100) in loose body fragments versus 92% viability (95% CI 50-100) from healthy cartilage. This study showed that cartilage from detached OCD fragments remains viable before reattachment is performed.