Endoscopic Repair of Partial Thickness Under-Surface Tears of The Abductor Tendon (pusta): Clinical Outcomes with Minimum Two-year Follow-up

OBJECTIVES: To report the minimum two-year outcomes of trans-tendinous repairs of Partial Thickness Undersurface Tears of the Abductor (PUSTA) tendon using patient reported outcomes (PROs), visual analog scale (VAS), and patient satisfaction scores. METHODS: All patients who underwent endoscopic trans-tendinous gluteus medius repair between October 2009 and May 2013 at one institution were prospectively evaluated. Exclusion criteria consisted of less than two-year follow-up, previous hip surgery, inflammatory arthritis, open surgery, full thickness abductor tear, and worker’s compensation patients. All patients had a documented pre-operative physical exam with strength testing (0-5) and observation of their gait. Patient satisfaction and PRO scores were recorded preoperatively, at 3 months postoperatively, and annually thereafter. The PRO scores collected were mHHS, HOS-ADL, HOS-SSS, NAHS, and VAS. Preoperative strength and gait were compared to latest follow-up. RESULTS: There were 25 patients that fit our criteria. Significant improvement in PRO scores were demonstrated for mHHS, HOS-ADL, HOS-SSS, NAHS, and VAS from 54.9-76.2, 50.2-80.6, 30.1-67.3, 51.9-82.4, and 7.1-2.7 respectively (p<0.001). There were 11 patients with objective weakness prior to surgery; seven of these patients moved up at least one strength grade by final follow-up. There were 14 patients who had a Trendelenbrug gait pre-operatively, 12 of them had a normal gait at latest follow-up (p-<0.001). Average patient satisfaction was 7.5. There were no revision surgeries, and no complications noted. CONCLUSION: PUSTA lesions can be treated successfully with endoscopic trans-tendinous repair preserving the intact attachment of superficial fibers of the gluteus medius. We recommend this treatment for partial undersurface tears recalcitrant to non-operative treatment, as patients demonstrated clinical benefit at greater than 2 years follow up that exceeds substantial clinical benefit and minimally clinical important difference.