RESUMEN
PURPOSE: To analyze the changes in fatty degeneration of the rotator cuff after its repair as well as the effect of fatty degeneration on the functional and anatomical outcomes. MATERIALS AND METHODS: The medical records of 107 patients (mean age=58.7 years), who had undergone a repair of rotator cuff tears, were reviewed. The mean follow-up period was 16 months. The following parameters were evaluated: the functional outcomes, including the American shoulder and elbow surgeons (ASES) score, Constant score and muscle power; preoperative and postoperative fatty degeneration of the rotator cuffs, including supraspinatus, infraspinatus and subscapularis; and the cuff integrity. RESULTS: Both the ASES and Constant scores were improved significantly postoperatively. The re-tear rate was 19.6%. The overall rate of satisfactory results was 88.8%. Fatty degeneration progressed in 25 cases (22.4%) and regressed in three (2.8%). More progression was observed in older (p=0.016) and re-tear (p=0.011) patients. The ASES score had a significant relationship with the preoperative fatty degeneration of the supraspinatus and the infraspinatus, whereas the Constant score was associated with the fatty degeneration of all three muscles. CONCLUSION: Greater progression of fatty degeneration was observed in older and re-tear patients. The functional outcomes were better in the less severe fatty degeneration group.