Factors Affecting Rotator Cuff Healing After Arthroscopic Repair: Osteoporosis as One of the Independent Risk Factors.

Background: The prognostic factors associated with structural outcome after arthroscopic rotator cuff repair have not yet been fully determined. Hypothesis: The hypothesis of this study was that bone mineral density (BMD) is an important prognostic factor affecting rotator cuff healing after arthroscopic cuff repair. Study Design: Cohort study; Level of evidence, 3. Methods: Among 408 patients who underwent arthroscopic repair for full-thickness rotator cuff tear between January 2004 and July 2008, 272 patients were included whose postoperative cuff integrity was verified by computed tomography arthrography (CTA) or ultrasonography (USG) and simultaneously who were evaluated by various functional outcome instruments. The mean age at the time of operation was 59.5 ± 7.9 years. Postoperative CTA or USG was performed at a mean 13.0 ± 5.1 months after surgery, and the mean follow-up period was 37.2 ± 10.0 months (range, 24-65 months). The clinical, structural, and surgery-related factors affecting cuff integrity including BMD were analyzed using both univariate and multivariate analysis. Evaluation of postoperative cuff integrity was performed by musculoskeletal radiologists who were unaware of the present study. Results: The failure rate of rotator cuff healing was 22.8% (62 of 272). The failure rate was significantly higher in patients with lower BMD (P < .001); older age (P < .001); female gender (P = .03); larger tear size (P < .001); higher grade of fatty infiltration (FI) of the supraspinatus, infraspinatus, and subscapularis (all P < .001); diabetes mellitus (P = .02); shorter acromiohumeral distance (P < .001); and associated biceps procedure (P < .001). However, in the multivariate analysis, only BMD (P = .001), FI of the infraspinatus (P = .01), and the amount of retraction (P = .03) showed a significant relationship with cuff healing failure following arthroscopic rotator cuff repair. Conclusion: Bone mineral density, as well as FI of the infraspinatus and amount of retraction, was an independent determining factor affecting postoperative rotator cuff healing. Further studies with prospective, randomized, and controlled design are needed to confirm the relationship between BMD and postoperative rotator cuff healing.