Focal chondral lesions at the knee have been shown to impaired quality of life and clinical function. As these lesions have little potential for spontaneous healing, surgical treatment options have often included microfracture and autotransplantation of osteochondral cylinders (mosaicplasty). This study compared the clinical outcomes of these two procedures.

Subjects were 40 patients, 18 to 50 years of age, presenting for repair of chondral lesions at the knee. The participants were randomized to receive either microfracture or mosaicplasty. For both procedures, continuous passive motion was started within hours after surgery, and continued for the duration of the hospitalization. The patients used crutches with toe-touch weight bearing for six weeks, progressing thereafter to full weight bearing. At baseline, and yearly up to 15 years postoperatively, the subjects completed a standardized form with questions concerning symptoms and function.

At 15 years, the mean Lysholm score improved 21 points from baseline in the mosaicplasty group and was significantly better than the microfracture group at one, five, 10 and 15 years. The mosaicplasty group contained a significantly higher number of patients who reported good/excellent outcomes (P＝0.01), and a lower percent who reported a poor outcome (P＝0.08), as compared with the microfracture group.

This study of patients with chondral defects of the knee found that mosaicplasty results in better short- and long-term outcomes, as compared to microfracture.