Efficacy of blood flow restriction training in upper extremity musculoskeletal disorders: a meta-analysis

This systematic review with meta-analysis aimed to compare the effects of traditional exercise (using low-load resistance training (LLRT) with and without blood flow restriction (BFR)) on functional outcomes, pain levels, muscle strength, and range of motion (ROM) in patients with upper extremity disorders. The primary distinction between the experimental and control interventions lies in the application of blood flow restriction during the exercise protocol.

Searches have been performed in the PubMed, Web of Science, Embase and Cochrane databases, together with the reference lists of randomized controlled trials (RCTs) up to March 2025. The participants in the RCTs were individuals with orthopedic abnormalities of the upper extremity arising from surgical intervention, trauma, or degenerative disorders, and the intervention was LLRT-BFR, as opposed to LLRT alone. The major focus was on assessing upper limb function and pain, with secondary considerations including muscle strength and ROM. The quality and reporting standards of the studies were evaluated via the TESTEX scale. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) was conducted to verify the quality of evidence. The means and standard deviations (SDs) of the pre- and post-intervention data were extracted from each study. The means and SDs of the change scores were calculated, and these values were imported into Review Manager software (The Nordic Cochrane Collaboration) to compute the standardized mean difference (SMD) as the effect size.

A systematic search across the aforementioned four databases initially identified 466 potentially relevant articles. Through a rigorous screening process, five articles that met the predefined inclusion criteria were ultimately selected for further analysis. These studies included 85 patients who underwent LLRT-BFR and 85 patients who received only LLRT. In patients with upper extremity dysfunction, the meta-analysis revealed significantly superior outcomes with LLRT-BFR compared with LLRT without BFR across multiple measures: pain reduction (SMD, 1.19; P=0.0002 [95% CI, 0.56-1.81]), functional improvement (SMD, 1.32; P=0.005 [95% CI, 0.39-2.24]), grip strength enhancement (SMD, 0.64; P=0.004 [95% CI, 0.20-1.07]), and radial flexion improvement (SMD, 0.81; P=0.003 [95% CI, 0.28--1.34]).

BFR combined with LLRT produced better outcomes than LLRT alone in terms of function, discomfort, grip strength, and wrist range of motion (ulnar deviation). For people with upper limb deficits, BFR combined with LLRT may have some potential as a complementary intervention, and further research is needed to establish its efficacy and safety, particularly in different patient populations.