Ten-year follow-up of a prospective, randomized clinical study of mosaic osteochondral autologous transplantation versus microfracture for the treatment of osteochondral defects in the knee joint of athletes.

BACKGROUND: Various techniques have proven to be effective for treating articular cartilage defect (ACD) and osteochondral defect (OCD) of the knee joint, but knowledge regarding which method is best still remains uncertain.

PURPOSE: To evaluate and compare the outcomes of mosaic-type osteochondral autologous transplantation (OAT) and microfracture (MF) procedures for the treatment of articular cartilage defects of the knee joint in young active athletes. This article represents an update of the clinical results at 10 years.

STUDY DESIGN: Randomized controlled trial; Level of evidence, 1.

METHODS: Between 1998 and 2002, a total of 60 athletes with a mean age of 24.3 years (range, 15-40 years) and with a symptomatic ACD or OCD in the knee were randomized to undergo either OAT or MF. Patients were then evaluated postoperatively using the International Cartilage Repair Society (ICRS) score, Tegner activity score, radiographs, and magnetic resonance imaging. The mean follow-up time was 10.4 years (range, 9-11 years).

RESULTS: Three to 10 years after the OAT and MF procedures, patients had lower ICRS and Tegner scores (P < .05), but both groups still had significant clinical improvement over presurgery scores according to ICRS scores at 10-year follow-up. Statistically significantly better results were detected in patients in the OAT group compared with those in the MF group at 10 years (P < .005). At 10-year follow-up, there were 15 failures (26%), including 4 failures (14%) of the OAT and 11 failures (38%) of MF treatment (P < .05). Seven patients (25%) from the OAT group and 14 patients (48%) from the MF group had radiographic evidence of Kellgren-Lawrence grade I osteoarthritis at 10 years, but these differences were not significant (P = .083) or related to the clinical results. The ICRS and Tegner scores of younger athletes (<25 years at the time of primary surgery) remained significantly higher after 10 years compared with older patients (P < .05); 15 of 20 patients (75%) in the OAT group and 8 of 22 patients (37%) in the MF group maintained the same physical activity level.

CONCLUSION: The OAT technique for ACD or OCD repair in the athletic population allows for a higher rate of return to and maintenance of sports at the preinjury level compared with MF.