Arthroscopic capsular release for frozen shoulder: when etiology matters

PURPOSE: No therapeutic intervention is universally accepted for frozen shoulder, and the most effective management to restore motion and diminish pain has yet to be defined. The aim of this study was to investigate functional and psychological outcomes in patients who underwent arthroscopic capsular release for a frozen shoulder. METHODS: A retrospective study with prospective data collection was conducted with 78 patients suffering from frozen shoulder resistance to conservative treatment. Considering the etiology, there were 36 (46.2%) idiopathic, 31 (39.7%) postoperative, and 11 (14.1%) posttraumatic cases. Preoperatively, each patient was evaluated with the range of motion (ROM) assessment and the Constant-Murley score (CMS). At follow-up, the 4-point subjective satisfaction scale (SSS), the ROM assessment, the SF-12 questionnaire, the numerical rating scale (NRS) for the subjective assessment of pain, the CMS and the Hospital Anxiety and Depression Scale (HADS) were assessed. RESULTS: After a mean follow-up of 54.2 ± 22.3 months, ROM and CMS showed a statistically significant improvement between pre- and postoperative values (all p < 0.001). Before surgery, the mean CMS was 36.9% that of sex- and age-matched healthy individuals, and all patients showed a CMS lower than the normative data. At the final follow-up visit, the mean CMS was 99.9% that of sex- and age-matched healthy individuals, and 49 (62.8%) patients showed a CMS equal to or higher than the normative data. The mean increase in the CMS was 56.1 ± 8.3 points. The mean SSS, HADS-A, HADS-D, and NRS were 3.7 ± 0.5, 2.5 ± 1.6, 2.2 ± 1.3, and 2.2 ± 1.0, respectively. All patients returned to their previous level of work and sports activity after 2 and 2.5 months, respectively. The multivariate analysis showed the association between a higher postoperative CMS and the idiopathic etiology of a frozen shoulder (p = 0.004, β = 3.971). No intraoperative complications occurred. Postoperatively, four patients (5.1%) were treated with intra-articular steroid injections to manage residual symptoms. One patient (1.3%) with a postoperative frozen shoulder showed persistent symptoms and underwent a new successful arthroscopic capsular release. CONCLUSION: High patient satisfaction and statistically significant ROM and CMS recovery can be achieved after arthroscopic capsular release to manage frozen shoulder. Better functional outcomes are expected when the etiology is idiopathic. Results can help surgeons identify the patients who will most benefit from surgery and should be discussed with the patient. LEVEL OF EVIDENCE: III.