Abstract
INTRODUCTION: Platelet-rich plasma (PRP) has been increasingly applied for rotator cuff pathology; however, clinical evidence regarding its short-term efficacy remains limited. This study evaluated the effectiveness of a single PRP injection for rotator cuff injury. METHODS: This single-center retrospective study analyzed 25 cases managed between August 2024 and August 2025 to evaluate the effectiveness of a single PRP injection for rotator cuff injury. Pain was assessed using the visual analog scale (VAS), and shoulder function was assessed using Shoulder 36 (Version 1.3) at baseline and at one, two, and three months. RESULTS: Mean VAS decreased from 7.48 at baseline to 4.76 at one month, 4.40 at two months, and 3.16 at three months, with significant improvements at all follow-up time points compared with baseline (paired t-test, p < 0.001). At three months, 20 of 25 cases (80.0%) achieved a VAS improvement of ≥2 points, and 16 of 25 cases (64.0%) achieved a ≥50% reduction from baseline. In the Shoulder 36, the domains of pain, range of motion, muscle strength, general health perception, and activities of daily living improved over time; pain and muscle strength improved significantly from one month, and range of motion, general health perception, and activities of daily living improved significantly at two and three months (all p < 0.05), whereas the sports ability domain did not reach statistical significance. No significant associations were observed between three-month improvements in VAS or Shoulder 36 and the interval from symptom onset to the first PRP injection, baseline Ultrasound Shoulder Pathology Rating Scale (USPRS) grade, or prior treatment (no treatment, hyaluronic acid, or corticosteroid). Retreatment was performed in six cases (24.0%), and PRP was selected in all cases; baseline characteristics and three-month VAS improvement did not differ significantly between cases with and without retreatment. CONCLUSION: In this single-center retrospective cohort of 25 cases, a single PRP injection was associated with significant improvements in VAS and multiple Shoulder36 domains over three months, and no apparent complications were observed during follow-up.