Intramuscular neuromuscular electric stimulation for poststroke shoulder pain: A multicenter randomized clinical trial

Objective: To assess the effectiveness of intramuscular neuromuscular electric stimulation (NMES) in reducing poststroke shoulder pain. Design: Multicenter, single-blinded, randomized clinical trial. Setting: Ambulatory centers of 7 academic rehabilitation centers in the United States. Participants: Volunteer sample of 61 chronic stroke survivors with shoulder pain and subluxation. Intervention: Treatment subjects received intramuscular NMES to the supraspinatus, posterior deltoid, middle deltoid, and trapezius for 6 hours a day for 6 weeks. Control subjects were treated with a cuff-type sling for 6 weeks. Main Outcome Measure: Brief Pain Inventory question 12 (BPI 12), an 11-point numeric rating scale administered in a blinded manner at the end of treatment, and at 3 and 6 months posttreatment. Results: The NMES group exhibited significantly higher proportions of success based on the 3-point or more reduction in BPI 12 success criterion at the end of treatment (65.6% vs 24.1%, P<.01), at 3 months (59.4% vs 20.7%, P<01), and at 6 months (59.4% vs 27.6%, P<.05). By using the most stringent "no pain" criterion, the NMES group also exhibited significantly higher proportions of success at the end of treatment (34.4% vs 3.4%, P<.01), at 3 months (34.4% vs 0.0%, P<001), and at 6 months (34.4% vs 10.3%, P<05). Conclusions: Intramuscular NMES reduces poststroke shoulder pain among those with shoulder subluxation and the effect is maintained for at least 6 months posttreatment.