Five-year results of arthroscopic techniques for the treatment of acetabular chondral lesions in femoroacetabular impingement

Abstract

Purpose: This study assesses and compares the clinical outcomes of the arthroscopic matrix-induced autologous chondrocyte implant (MACI) and autologous matrix-induced chondrogenesis (AMIC) techniques for the treatment of acetabular chondral defects between 2 and 4 cm(2) consequent to femoral acetabular impingement.

Methods: Fifty-seven consecutive patients were treated with the MACI (n = 26) or AMIC (n = 31) technique. Patients were assessed pre-operatively and up to five years using the modified Harris Hip Score (mHHS) to compare outcomes.

Results: In both the MACI and AMIC groups, significant hip score improvements were measured over baseline levels at six months post-op (81.2 ± 8.4 for MACI, 80.3 ± 8.3 for AMIC, both p < 0.001). The mHHS continued to improve up to three years post-op and remained stable over time until the final five year follow-up. Statistically significant differences between the groups were not observed. The mean mHHS improvement at the five year follow-up with respect to preoperative level was 37.8 ± 5.9 and 39.1 ± 5.9 in patients who underwent MACI and AMIC, respectively (NS). Subgroup analysis of both MACI and AMIC treatment outcomes for patients with an initial chondral defect larger than 3 cm(2) yielded comparable results at each time point.

Conclusions: This study suggests that both arthroscopic MACI and AMIC are valid procedures to repair medium-sized chondral defects on the acetabular side of the hip found during treatment of femoroacetabular impingement. Due to its high sustainability and minimal invasiveness, the single-stage AMIC procedure can reduce total treatment time and minimise morbidity while providing the same beneficial effects as the two-stage MACI intervention.