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

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.