Sixty patients with chronic rotator cuff (RC) tendinopathy were randomized to receive an intra-articular corticosteroid injection (n=30) or prolotherapy consisting of subcutaneous injections of dextrose (n=30). Outcomes of interest included pain measured on a visual analogue scale (VAS), % of patients achieving a clinically significant reduction (≥2.8) in VAS pain scores, and range of motion (i.e., external rotation, abduction, and flexion) at 1-month follow-up. Results revealed that VAS pain at 1 month follow-up was not statistically significantly different between the corticosteroid and prolotherapy groups (p=0.052). However, a higher % of patients achieved a clinically significant reduction in VAS pain in the prolotherapy group vs corticosteroid group (p=0.046) at 1 month follow-up. Interestingly, range of motion in flexion, abduction, and external rotation were higher in the corticosteroid group vs. prolotherapy at 1 month follow-up. No patient in either group reported an adverse event.