Revision Rotator Cuff Repair Versus Primary Repair for Large to Massive Tears Involving the Posterosuperior Cuff: Comparison of Clinical and Radiological Outcomes

BACKGROUND: The retear rate after revision rotator cuff repair (rRCR) ranges from 50% to 90%. Patients who undergo primary RCR (pRCR) for large to massive rotator cuff tear (mRCT) also have unpredictable outcomes. PURPOSE: To compare the clinical outcomes after rRCR for a posterosuperior rotator cuff tear of any size with those after pRCR for mRCT and to identify the risk factors for poor outcomes and retear after rRCR. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: Among patients with posterosuperior cuff tear treated between 2010 and 2017, the clinical outcomes of 46 patients who underwent rRCR were compared with 106 patients who underwent pRCR for mRCT. Between-group differences in patient-reported outcomes (visual analog scale [VAS] for pain, VAS for satisfaction and American Shoulder and Elbow Surgeons [ASES] and Constant scores) at final follow-up were evaluated and compared with previously published minimal clinically important difference (MCID) values. Radiological outcomes were evaluated using magnetic resonance imaging or ultrasonography at a minimum 1-year follow-up. Multivariate linear regression analysis was performed to identify the risk factors for poor ASES score, and multivariate logistic regression analysis was used to assess the risk factors for retear after rRCR. RESULTS: The mean follow-up was 26.4 months (range, 24-81 months). Although final VAS for pain, VAS for satisfaction, and ASES scores in the rRCR group were significantly worse than those in the pRCR group, the Constant score was similar between the groups. These differences in outcomes did not exceed the MCID threshold. The retear rate in the rRCR group was 50% compared with 39% for the pRCR group (P = .194). In the rRCR group, risk factors for worse ASES score were retear (P = .043; r = –11.3), lower body mass index (P = .032; r = 1.9), and lower preoperative VAS for pain (P = .038; r = 2.3), and risk factors for retear were preoperative high-grade fatty degeneration (Goutallier grades 3 and 4) of the supraspinatus muscle (P = .026; odds ratio, 5.2) and serum hyperlipidemia (P = .035; odds ratio, 11.8). CONCLUSION: Both study groups had similar clinical and radiological outcomes. Patients with symptomatic failed rotator cuff repairs having high-grade fatty degeneration of the supraspinatus muscle and/or serum hyperlipidemia had a greater likelihood of retear after rRCR.