Addition of low-load blood flow restriction training to conventional physiotherapy improves handgrip strength and function in patients with lateral epicondylitis at the short-term: A single-blind randomized clinical trial

Background: Evidence regarding Blood Flow Restriction (BFR) training for the management of lateral epicondylitis (LE) remains limited and conflicting, although BFR has shown potential to improve muscle strength in other musculoskeletal rehabilitation settings. Objective: To investigate the short-term effects of adding low-load BFR training to a conventional physiotherapy (CPT) program on handgrip strength (HGS), function, and pain intensity during rest and activity, in patients with LE. Design: A single-blind, randomized clinical trial. Methods: Fifty-two participants with LE were randomly allocated to either the CPT group or the CPT + BFR group. Both groups received 12 sessions over 6 weeks. The primary outcome was HGS using a hand-held dynamometer. Secondary outcomes were Patient-Rated Tennis Elbow Evaluation (PRTEE) scores, Numerical Pain Rating Scale (NPRS) scores, and satisfaction with treatments. These outcome measures were reassessed at the end of the six-week intervention period. Results: Both groups demonstrated statistically significant within-group improvements in HGS, PRTEE, and NPRS outcomes (all p < 0.001). Mean HGS increased by 17.50 ± 2.53 lb in the CPT group and by 35.54 ± 0.71 lb in the CPT + BFR group. The post-treatment HGS difference strongly favoured CPT + BFR (Mann–Whitney U = 30.0, p < 0.001; rank-biserial correlation r_rb = 0.911, 95% CI 0.800 to 0.984). PRTEE also favoured CPT + BFR, whereas no statistically significant between-group differences were observed for NPRS pain scores or treatment satisfaction. Conclusion: In patients with LE, addition of low-load BFR training to CPT resulted in greater short-term improvements in HGS and function, while pain reduction was comparable between groups.