The influence of diabetes mellitus on clinical and structural outcomes after arthroscopic rotator cuff repair

Background: The clinical effect of sustained hyperglycemia on tendon-to-bone healing after rotator cuff repair has not been well characterized.

Purpose: To compare the clinical and structural outcomes between diabetic and nondiabetic patients after arthroscopic rotator cuff repair and to determine the effect of a diabetic phenotype on tendon-to-bone healing.

Study design: Cohort study; Level of evidence, 3.

Methods: This study retrospectively evaluated a total of 335 shoulders that were available for magnetic resonance imaging (MRI) evaluation at least 6 months after arthroscopic rotator cuff repair using the suture-bridge technique with a minimum follow-up of 1 year. Only patients who had medium- to large-sized tears with supraspinatus of fatty infiltration <2 and no or mild atrophy were enrolled in this study. There were 271 nondiabetic patients (group A) and 64 diabetic patients (group B). The mean age at the time of operation for groups A and B was 57.7 and 58.2 years, respectively, and the mean duration of follow-up after surgery was 27.8 and 24.8 months, respectively.

Results: At the last follow-up, there were no statistically significant differences between the 2 groups with regard to pain at rest and during motion (P = .212 and .336, respectively). Both groups reported statistically significant improvement in Constant and Shoulder Rating Scale of the University of California at Los Angeles scores (P = .323 and .241, respectively), but there was no statistically significant difference between the 2 groups. In assessing the repair integrity with postoperative MRI scans, 39 of 271 cases in group A (14.4%) and 23 of 64 cases in group B (35.9%) had retears, and the difference between the 2 groups was statistically significant (P < .001). In analyzing the retear rates according to the severity of sustained hyperglycemia in group B, retear was found in 16 of 37 (43.2%) uncontrolled diabetic patients with poor glycemic control (≥7.0% of preoperative serum glycosylated hemoglobin [HbA1c] levels) and in 7 of 27 (25.9%) controlled diabetic patients (<7.0%) (P < .001).

Conclusion: Pain, range of motion, and function all significantly improved after arthroscopic rotator cuff repair using the suture-bridge technique, regardless of the presence of diabetes. However, sustained hyperglycemia increased the possibility of anatomic failure at the repaired cuff. In diabetic patients, an effective glycemic control was associated with better rate of healing after rotator cuff repair.