Endoscopic Repair of Partial-Thickness Undersurface Tears of the Abductor Tendon: Clinical Outcomes With Minimum 2-Year Follow-up.

Purpose: To report the minimum 2-year outcomes of transtendinous repair of partial-thickness undersurface tears of the abductor tendon using patient-reported outcomes (PROs), visual analog scale (VAS) scores, and patient satisfaction scores.

Methods: All patients who underwent endoscopic transtendinous gluteus medius repair between October 2009 and May 2013 at 1 institution were prospectively evaluated. The exclusion criteria consisted of less than 2 years' follow-up, previous hip surgery, inflammatory arthritis, open surgery, full-thickness abductor tear, and Workers' Compensation patients. All patients underwent a documented preoperative physical examination with strength testing (scale of 0-5) and observation of their gait. Patient satisfaction and PRO scores were recorded preoperatively; at 3 months postoperatively; and at 1, 2, 5, and 10 years after surgery. The PRO scores collected were the modified Harris Hip Score, Hip Outcome Score-Activities of Daily Living Subscale, Hip Outcome Score-Sports-Specific Subscale, Non-arthritis Hip Score, and VAS score. Preoperative strength and gait were compared with latest follow-up.

Results: There were 25 patients who fit our criteria. Significant improvement in PRO scores were shown for the modified Harris Hip Score, Hip Outcome Score-Activities of Daily Living Subscale, Hip Outcome Score-Sports-Specific Subscale, Non-arthritis Hip Score, and VAS score from 54.9 to 76.2, from 50.2 to 80.6, from 30.1 to 67.3, from 51.9 to 82.4, and from 7.1 to 2.7, respectively (P < .001). Before surgery, 11 patients had objective weakness; 7 of these patients moved up at least 1 strength grade by final follow-up. Preoperatively, 14 patients had a Trendelenburg gait; 12 of them had a normal gait at latest follow-up (P < .001). The average patient satisfaction rating was 7.5. There were no revision surgical procedures, and no complications were noted.

Conclusions: Partial-thickness undersurface tears of the abductor can be treated successfully with endoscopic transtendinous repair preserving the intact attachment of the superficial fibers of the gluteus medius. We recommend this treatment for partial undersurface tears recalcitrant to nonoperative treatment because patients showed clinical benefit at greater than 2 years' follow-up that exceeded substantial clinical benefit and the minimal clinically important difference.

Level Of Evidence: Level IV, case series.