Effects of Electrical Muscle Stimulation for Preventing Deltoid Muscle Atrophy after Rotator Cuff Repair: Preliminary Results of a Prospective, Randomized, Single-blind Trial

BACKGROUND: This study investigates the effects of neuromuscular electrical stimulation (NMES) in preventing deltoid atrophy during the first 12 weeks after arthroscopic rotator cuff repair. METHODS: Eighteen patients undergoing arthroscopic repair of a medium-sized rotator cuff tear by a single surgeon, were randomized into two groups: NMES and transcutaneous electrical nerve stimulation (TENS). Each group used the respective device for 6 weeks after surgery. Pain was measured at baseline, 6, and 12 weeks postoperatively, using the visual analogue scale (VAS); range of motion (ROM), abduction strength and functional scores were measured at baseline and 12 weeks postoperatively. Deltoid thickness and cross-sectional areas were measured using magnetic resonance imaging at 12 weeks postoperatively. RESULTS: At 12 weeks post-surgery, no statistically significant difference was observed between the NMES and TENS groups in the pain VAS, the Disabilities of the Arm, Shoulder and Hand score, ROM, and abduction strength. Postoperative decrease in the thickness of the anterior, middle, and posterior deltoid, at the level just below the coracoid, was -2.5%, -0.7%, and -6.8%, respectively, in the NMES group, and -14.0%, -2.6%, and -8.2%, respectively, in the TENS group (p=0.016, p=0.677, and p=0.791, respectively). At the level of the inferior glenoid tubercle, postoperative decrease in area of the deltoid was -5.4% in the NMES group and -14.0% in the TENS group, which was significantly different (p=0.045). CONCLUSIONS: NMES has the potential for reducing deltoid atrophy after arthroscopic rotator cuff repair, suggesting that NMES might help minimize postoperative atrophy after various shoulder surgeries.