Surgically Repaired Massive Rotator Cuff Tears: MRI of Tendon Integrity, Muscle Fatty Degeneration, and Muscle Atrophy Correlated with Intraoperative and Clinical Findings

OBJECTIVE: Our goal in this study was to evaluate by means of MRI the clinical significance of tendon integrity, muscle fatty degeneration, and muscle atrophy in surgically repaired massive rotator cuff tears and to correlate these and other prognostic factors with intraoperative and clinical findings. MATERIALS AND METHODS: Twenty-eight surgically proven massive rotator cuff tears were retrospectively included in the study. Twenty-two patients underwent complete repair, and six patients underwent partial repair. Preoperative and postoperative clinical assessment was performed by using the University of California at Los Angeles score. Preoperative and postoperative MRI studies were evaluated for the presence and extent of rotator cuff tear and for the degree of fatty degeneration and atrophy of the rotator cuff muscles. RESULTS: At a mean 44.4 months' follow-up, 20 patients (71.4%) had a favorable result. A total of 25 patients (89.2%) showed postoperative full-thickness rotator cuff tear, 19 of which were reruptures. A sagittal preoperative rotator cuff tear of less than or equal to 34 mm showed a specificity of 100% for predicting a favorable outcome. A coronal postoperative rotator cuff tear of less than or equal to 34 mm showed a specificity of 85.7% and a positive predictive value of 92.9% for predicting a favorable outcome. A postoperative fatty degeneration of infraspinatus muscle less than or equal to 2 had a specificity of 87.5% and a positive predictive value of 90.9% for predicting a favorable outcome. CONCLUSION: Open repair of massive rotator cuff tears may reach a favorable outcome in a significant proportion of patients, despite a high rate of recurrent or residual tears. Oblique coronal sizes of the recurrent or residual tear of less than or equal to 34 mm and postoperative fatty degenerations of infraspinatus muscle of less than or equal to 2 may allow a favorable outcome.