Effect of Preoperative Frozen Shoulder on Clinical Outcomes After Arthroscopic Rotator Cuff Repair

BACKGROUND: A concomitant rotator cuff tear (RCT) with frozen shoulder is a common but challenging clinical scenario. The effect of frozen shoulder on clinical outcomes is open to discussion. PURPOSE/HYPOTHESIS: This study aimed to evaluate the effect of preoperative frozen shoulder on postoperative clinical outcomes of an RCT. We hypothesized that the treatment results of an RCT concomitant with preoperative frozen shoulder would be comparable with those of an isolated RCT. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A total of 212 patients were divided into 2 groups: 154 in the non–frozen shoulder (NFS) group and 58 in the preoperative frozen shoulder (FS) group. All patients underwent a thorough preoperative evaluation that included range of motion (ROM) and the pain visual analog scale, functional visual analog scale, Constant score, and American Shoulder and Elbow Surgeons (ASES) score. The same evaluation was performed at 6 months and 1 and 2 years postoperatively. The healing status of the repaired RCT of all patients was evaluated by postoperative magnetic resonance imaging. RESULTS: The FS group showed statistically significantly worse functional outcomes than the NFS group at 6 months and 1 year postoperatively (P < .05). At 2 years postoperatively, active assisted ROM was equivalent between the groups, although the ASES and Constant scores were significantly lower for the FS group (P < .033 and P < .001, respectively). The retear rates were 5.3% and 12.3% for the FS and NFS groups, respectively (P = .013). CONCLUSION: Preoperative frozen shoulder positively affected rotator cuff healing but negatively affected most functional outcomes, including ROM, at 6 months and 1 year postoperatively. At 2 years after surgery, there was no significant difference in active motion, but outcome scores remained lower in the FS group. For patients with preoperative frozen shoulder, a delay in surgery for additional physical therapy might not be necessary. The retear rate for the NFS group was more than double that for the FS group in the current study, which indicates that surgery for an RCT combined with frozen shoulder might provide better results in the long term because of an intact, healed rotator cuff.