Autologous osteochondral transplantation (mosaicplasty) in articular cartilage defects of the patellofemoral joint: retrospective analysis of 33 cases.

ABSTRACT

OBJECTIVE: The purpose of this retrospective study was to evaluate the results of osteochondral autografting (mosaicplasty) in isolated articular cartilage defects of the patellofemoral joint. MATERIALS AND METHODS: Thirty-three patients who underwent mosaicplasty for patellofemoral (either patella or trochlea) cartilage defects (modified Outerbridge classification grades III and IV) of the knee joint were retrospectively reviewed. There were 25 male and 8 female patients with a mean age of 31.3 ± 6.7 (range 22-47) years. The average size of the lesion was 2.4 ± 0.55 cm2 (range 1.5-4.0). Patients with patellofemoral malalignment were excluded. All patients were followed at least one year with a mean of 19.3 ± 4.3 months (range 12-24 months) using Lysholm knee score. RESULTS: The mean preoperative Lysholm knee score was 51.9 ± 2.6 (47-58) points and increased to 85.5 ± 4.2 (75-89) points at the final follow-up. There was a significant increase in Lysholm score during follow-up period (p = 0.0001). The results were good in 24 cases and fair in 9 cases. No patients had poor results. No patients had infection. Five patients had postoperative mild painful hemarthrosis. Of these patients, four were treated with rest, ice, compression (elastic bandage) and elevation and the remaining one was treated by aspiration. No patients needed secondary open or arthroscopic drainage. No systemic complications occurred during the follow-up. CONCLUSIONS: Mosaicplasty is an effective technique for the treatment of articular cartilage defects of the patellofemoral joint knee which restores the joint function in a short period of follow-up. However, a meticulous surgical technique should be followed to restore the native articular surface and the congruity of the joint.