High prevalence of acetabular rim osteophytes after hip arthroscopy for treatment of FAI

BACKGROUND: Few studies mentioned acetabular rim osteophytes (ARO) after arthroscopy for femoroacetabular impingement (FAI) in follow-up after primary hip arthroscopy. We found that many patients had postoperative ARO, which may lead to recurrent or secondary pincer-type deformity after primary hip arthroscopy for FAI and postoperative ARO sometimes even led to revision surgery. It is necessary to carry out related research on ARO. METHODS: We respectively evaluated consecutive cases who underwent hip arthroscopy in our hospital between January 2008 and January 2020. Radiographic examination was obtained for all patients preoperatively and postoperatively. Another CT scan was performed at least 6 months after surgery at final follow-up. Preoperative patient-reported outcomes (PROs) and PROs at final follow-up were obtained, including visual analog scale (VAS) for pain and modified Harris Hip Score (mHHS). The volume of ARO was calculated using mimics 21.0 software. According to the material of anchors and whether the anchors were used, patients were divided into absorbable group, non-absorbable group and no anchor group. RESULTS: A total of 71 patients were finally included in this study. Patients with postoperative ARO had higher VAS at final follow-up (P<0.05). Patients without postoperative ARO had higher mean mHHS at final follow-up (P = 0.08) and higher percentage of passing minimal clinical important difference. The percentage and volume of postoperative ARO was significantly higher in patients who underwent acetabuloplasty and labral repair (P<0.05). The percentage and volume of postoperative ARO in absorbable group were significantly higher than the other groups (P<0.05). CONCLUSION: There is a high percentage of ARO after hip arthroscopy for treatment of FAI and patients who have undergone labral repair and acetabuloplasty are more likely to have postoperative ARO. Using of absorbable anchors may increase the possibility and volume of postoperative ARO. Postoperative ARO may predict a worse clinical outcome.