Does Additional Dietary Supplementation Improve Physiotherapeutic Treatment Outcome in Tendinopathy? A Systematic Review and Meta-Analysis

A systematic review and meta-analysis of randomized controlled trials was performed to evaluate the effects of dietary supplements in addition to physiotherapeutic treatment on pain and functional outcomes. PubMed, The Cochrane Library, Web of Science, and Embase were searched from inception to November 2021 (Prospero registration: CRD42021291951). Studies were eligible if the interventions consisted of physiotherapeutic approaches that were combined with dietary supplementation and if they reported measures of pain and/or function. Six studies were included in the meta-analysis. Standardized mean differences (SMD) and 95% confidence intervals (CI) were calculated and analysed using a Review Manager software. Subgroup analysis was performed to explore possible associations between the study characteristics and the effectiveness of the intervention. Additional dietary supplementation during physiotherapeutic treatment significantly improved the reduction in pain score (SMD = −0.74, 95% CI, −1.37 to −0.10; p < 0.05), while it had no effect on functional outcomes (SMD = 0.29, 95% CI, 0.00 to 0.58; p > 0.05). This systematic review and meta-analysis suggests that additional nutritional interventions may improve physiotherapeutic treatment outcomes in the management of tendinopathies.