Does the femoral cam lesion regrow after osteoplasty for femoroacetabular impingement? Two-year follow-up.

BACKGROUND There are currently no studies that have examined the recurrence of the cam lesion after femoral neck osteoplasty for femoroacetabular impingement. Although patient-reported outcome (PRO) scores at midterm follow-up have shown continued success, the maintenance of a normalized alpha angle has not been shown radiographically. PURPOSE To assess the radiographic recurrence of cam deformity at 2-year follow-up after adequate decompression during the index hip arthroscopic procedure and correlate the findings with PRO scores. The hypothesis was that there would be no recurrence or regrowth of the cam deformity at the 2-year postoperative time point after adequate cam decompression during hip arthroscopic surgery. STUDY DESIGN Case series; Level of evidence, 4. METHODS Between March 2009 and January 2011, data were prospectively collected on all patients undergoing hip arthroscopic surgery with femoral neck osteoplasty. Minimum follow-up was 2 years, with radiographic images for review. RESULTS A total of 47 patients met the inclusion criteria. The mean age of the participants at the start of the study was 37.18 years (range, 31.70-47.43 years). There were 28 men (59.57%) and 19 women (40.43%). The mean follow-up duration was 28.32 months (range, 24-41 months). The mean preoperative alpha angle (Dunn view) was 70° (range, 60°-97°), compared with 42.79° (range, 32°-50°) at 2 weeks postoperatively (P < .0001). The mean 2-year alpha angle was 42.72° (range, 32°-54°), which was not significantly different compared with the mean 2-week alpha angle (P = .93). Additionally, the mean femoral offset measurement was 3.7 mm (range, 0-9.9 mm) preoperatively and 7.8 mm (range, 0.3-13.9 mm) 2 weeks postoperatively (P < .0001). The mean 2-year postoperative femoral offset measurement was 8.0 mm (range, 2.4-12.8 mm), which was not significantly different compared with the mean 2-week femoral offset measurement (P = .63). All PRO scores were significantly improved at 3 months compared with preoperative scores and, except for visual analog scale score, continued to show improvement at 2-year follow-up. CONCLUSION There was no recurrence of cam deformity at 2 years after femoral neck osteoplasty for femoroacetabular impingement. PRO scores were improved at the 3-month and 2-year postoperative time points.