Non-surgical and rehabilitative interventions in patients with frozen shoulder: umbrella review of systematic reviews

Background: Frozen shoulder (FS) is a painful condition characterized by progressive loss of shoulder function with passive and active range of motion reduction. To date, there is still no consensus regarding its rehabilitative treatment for pain management. Purpose: The aim of this umbrella review of systematic reviews was to analyze the literature, investigating the effects of non-surgical and rehabilitative interventions in patients suffering from FS. Patients and Methods: A review of the scientific literature was carried out from 2010 until April 2020 using the following search databases: PubMed, Medline, PEDro, Scopus and Cochrane Library of Systematic Reviews. A combination of terms was used for the search: frozen shoulder OR adhesive capsulitis AND systematic review OR meta-analysis AND rehabilitation NOT surgery NOT surgical intervention. We included systematic reviews that specifically dealt with adults with FS, treated with non-surgical approaches. All the systematic reviews and meta-analyses included in the study that met the inclusion criteria were assessed using the Assessment of Multiple Systematic Reviews as a quality assessment tool. Results: Out of 49 studies, only 14 systematic reviews respected the eligibility criteria and were included in this study. Their results showed an important heterogeneity of the studies and all of them agree on the lack of high-quality scientific work to prove unequivocally which rehabilitative treatment is better than the other. Due to this lack of gold standard criteria, there may be also a heterogeneity in the diagnosis of the reviews analyzed. Conclusion: Non-surgical and rehabilitative interventions are undoubtedly effective in treating FS, but there is no evidence that one approach is more effective than the other regarding the methods reported. Future high-quality RCTs are needed to standardize the treatment modalities of each physiotherapy intervention to provide strong recommendations in favor.