Triangular Forearm Support in Rotator Cuff Syndrome a randomized crossover trial with EMG insight into mechanism of action

Design: Randomized blinded control crossover of yoga-like maneuver treating MRI confirmed rotator cuff syndrome (RCS); minimum 29-month follow-up. Patient selection : RCS pain >5/10 on visual analogue scale (VAS). Intervention (80) and placebo (87) groups. Intervention : Triangular forearm support (TFS). Main outcome measures : VAS, shoulder kinetics. Methods : Patient-rated abduction and flexion pain pre – and post – TFS, and multi-channel EMG. Results : Intervention group: Abduction: mean post-TFS and post-placebo VAS dropped 1.98 and 1.08 points from 6.14 and 5.03 respectively or 32.3% vs. 21%, respectively. Flexion: baseline intervention group values: 5.13 and 4.57 dropped 1.08 and .93 points, 32% and 20.4% lower, respectively. (p =.002; p <.008). Placebo group’s crossover post TFS: mean abduction and flexion VAS dropped 1.25 and 1.39 respectively. All tests: p < .001. Mean 52-month follow-up for all patients: abduction and flexion VAS: mean improvement from initial post-TFS VAS: 0.92 points (95% CI: 0.13 to 1.71), p = 0.02 and 1.13 points (95% CI 0.54 - 1.73), p <0.001) respectively. VAS values for abduction and flexion were 67.6% and 74.5% below baseline. Post-TFS EMG of abduction showed greater activation of the subscapularis, less in deltoid, suggesting cantilevering the humerus upward between 80 – 110 degrees. Conclusion: The TFS maneuver may be helpful in RCS by employing a cantilever mechanism in abduction and flexion.