Prognostic Factors Affecting Rotator Cuff Healing After Arthroscopic Repair in Small to Medium-sized Tears

BACKGROUND: Small and medium-sized rotator cuff tears usually have good clinical and anatomic outcomes. However, healing failure still occurs in some cases. PURPOSE: To evaluate prognostic factors for rotator cuff healing in patients with only small to medium-sized rotator cuff tears. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: Data were prospectively collected from 339 patients with small to medium-sized rotator cuff tears who underwent arthroscopic repair by a single surgeon between March 2004 and August 2012 and who underwent magnetic resonance imaging or computed tomographic arthrography at least 1 year after surgery. The mean age of the patients was 59.8 years (range, 39-80 years), and the mean follow-up time was 20.8 months (range, 12-66 months). The functional evaluation included the visual analog scale (VAS) for pain, American Shoulder and Elbow Surgeons score, Constant-Murley score, and Simple Shoulder Test. RESULTS: Postoperative VAS for pain and functional scores improved significantly compared with preoperative values (P 2 cm in size (34.2%) compared with patients with a tear ≤2 cm (10.6%) (P < .001). A receiver operating characteristic curve was used to determine the predictive cut-off value for the oldest age and the largest tear size for successful healing, which were calculated as 69 years and 2 cm, respectively, with a specificity of 90%. CONCLUSION: In small to medium-sized rotator cuff tears, grade II fatty degeneration of the infraspinatus muscle according to the Goutallier classification could be a reference point for successful healing, and anatomic outcomes might be better if repair is performed before the patient is 69 years old and the tear size exceeds 2 cm.