Femoral head mosaicplasty provides good-to-excellent clinical scores at 10 years in patients with small osteochondral lesions

To report on outcomes at ≥7 years follow-up of patients with osteochondral lesions of the femoral head that underwent hip mosaicplasty through minimally invasive direct anterior approach. The cohort comprised 17 men and 7 women (24 hips) aged 28.7 ± 7.4 years with body mass index of 23.3 ± 2.8 kg/m2. Complications and reoperations were noted, and the modified Harris hip score (mHHS) and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) were assessed. Descriptive statistics were used to summarize the data. Two subgroup analyses were performed: lesion size <2 cm2 versus lesion size ≥2 cm2, and conversion to total hip arthroplasty (THA) versus no THA conversion. Three patients were lost-to-follow-up and 6 patients were converted to THA at 5.1 ± 3.5 years (range, 2–12). At 9.5 ± 1.9 years follow-up (range, 7–14), the remaining 15 patients reported mHHS of 87.2 ± 10.1 and WOMAC of 84.1 ± 12.3. Compared to patients with lesion size <2 cm2, patients with lesion size ≥2 cm2 tended to have greater proportion of THA conversion (57% versus 12%), lower postoperative mHHS (78.5 ± 14.9 versus 89.4 ± 8.0), and lower postoperative WOMAC (57.9 ± 11.5 versus 41.2 ± 16.9). Compared to patients without THA conversion, patients with THA tended to have more women (50% versus 22%), more femoroacetabular impingement (67% versus 39%), and greater lesion size (2.3 ± 0.9 cm2 versus 1.4 ± 0.5 cm2). Femoral head mosaicplasty provides good-to-excellent clinical scores at 10 years follow-up, although 25% of patients were converted to THA. Larger lesion size seemed to be associated with worse postoperative outcomes and greater rates of conversion to THA, suggesting that mosaicplasty may not be effective for lesions ≥2 cm2.