Arthroscopic Hip Revision Surgery for Residual FAI: Surgical Outcomes

OBJECTIVES: There is a steep surgical learning curve when managing femoroacetabular impingement (FAI) and residual FAI can lead to continued pain and disability. There is very limited data reporting outcomes after revision arthroscopy for residual FAI. METHODS: The records of patients that underwent arthroscopic hip revision surgery for residual FAI based on plain radiographs and 3D CT scans were reviewed. Pre and post-operative structural pathomorphology, intra-operative findings, and pre and post-operative outcomes measures using Modified Harris Hip Scoring (MHHS), SF-12 scoring, and pain on a visual analogue scale (VAS) were evaluated. Outcomes after revision arthroscopic FAI correction were compared to a cohort that underwent primary arthroscopic FAI correction. RESULTS: 59 patients (85 hips) underwent arthroscopic revision FAI correction (mean 20.8 months follow-up). There were 98 previous arthroscopic surgeries and 4 previous surgical dislocations. There were 39 males and 46 females with a mean age of 29.5 years (range 16 - 59). 80 hips had residual cam-type FAI, and 64 hips had residual pincer-type FAI and underwent femoral and rim resections, respectively. The labrum was debrided in 27 hips, repaired in 48 hips and reconstructed with allograft in 8 hips. Adhesions were excised for 54 hips. The results of revision arthroscopic FAI correction were compared to 154 patients (169 hips) that underwent primary arthroscopic FAI correction (mean 25.2 months follow-up). The mean improvement for outcomes scores after revision FAI correction was 18.9 points (MHHS, p<.01), 13.4 points (SF-12, p<.01), and 2.2 points (VAS, p<.01) compared to 23.7 points (MHHS, p<.01), 22.3 points (SF-12, p<.01), and 4.6 points (VAS, p<.01) after primary arthroscopic FAI correction. Most recent outcomes scores and mean improvement in outcome scores were significantly better after primary (81.1% good/ excellent results) compared to revision (69.8% good/excellent results) FAI correction (MHS (p>.05), SF-12 (p<.01), VAS (p<.01). CONCLUSION: With appropriate indications and expectations, arthroscopic hip revision surgery for residual FAI led to significantly improved outcome measures. Outcomes, however, were inferior to those after primary arthroscopic FAI corrective surgery.