Study Summary

116 patients with chronic shoulder pain due to subacromial impingement syndrome (SIS) were randomized to receive standardized physical therapy + axillary motor stimulation or standardized physical therapy + no stimulation. The primary outcome of interest was worst shoulder pain in the previous week measured by the Brief Pain Inventory Short Form (BPI-SF Q3). Secondary outcomes included shoulder pain and disability (SPADI), upper-extremity functional performance (FIT-HaNSA), quality of life (SF-12 PCS and MCS), and global impression of change. Outcomes were assessed at baseline, 8 weeks, and at 12 and 24-week follow-up after treatment. Overall, the results of the study revealed that both groups experienced significant improvements in pain, function, disability, and quality of life over time. There were no significant differences between groups for any primary or secondary outcome. These findings suggest that a standardized physical therapy program is effective for chronic SIS and that adding axillary motor stimulation does not provide additional clinical benefit.