Comparison of Knotless Versus Knot-Tying Suture Anchors for Arthroscopic Repair of Hip Labral Tears

Background: Both knotless and knot-tying anchors are commonly employed in the arthroscopic repair of hip labral tears. Purpose: To compare the midterm clinical results of arthroscopic hip labral repair using knot-tying versus knotless suture anchors. Study Design: Cohort study; Level of evidence, 3. Methods: Patients who underwent arthroscopic hip labral repair between January 2017 and January 2021 and who had at least 2 years of follow-up were included. The patients were divided into 2 groups based on the suture anchor type: a 2.9-mm knotless suture anchor (knotless group) or a 1.8-mm knot-tying suture anchor (knot-tying group). All patients underwent femoroplasty for cam lesions and acetabular rim trimming for pincer lesions. The modified Harris Hip Score (mHHS), Hip Outcome Score-Sport-Specific Subscale (HOS-SSS), Hip Outcome Score-Activities of Daily Living (HOS-ADL), 12-item International Hip Outcome Tool (iHOT-12), and visual analog scale (VAS) for pain were administered both preoperatively and postoperatively. The consistency of the outcome scores was assessed using the minimal clinically important difference and Patient Acceptable Symptom State. The statistical significance between groups was evaluated using the Mann-Whitney test and quantile-based analysis of variance. Results: A total of 413 patients were included: 256 patients in the knotless group (median age, 35 years [interquartile range, 31-38 years]; median follow-up, 34 months) and 157 patients in the knot-tying group (median age, 34 years [interquartile range, 30-38 years]; median follow-up, 25 months). There were no significant differences in postoperative mHHS, HOS-ADL, or iHOT-12 scores between the 2 groups. However, there were significant differences, favoring the knotless group over the knot-tying group, in postoperative HOS-SSS (87 +/- 2 vs 86 +/- 1, respectively) and VAS pain (1 vs 2, respectively) scores (P < .0001 for both). Postoperative synovitis was found in significantly more patients in the knot-tying group than in the knotless group (17 vs 5, respectively; P = .01). Conclusion: In this study, patients who underwent arthroscopic hip labral repair with knotless suture anchors had slightly better postoperative HOS-SSS and VAS pain scores and a lower incidence of postoperative synovitis compared with patients who underwent repair with knot-tying suture anchors.