Clinical and Metabolic Predictors of Response to Focused Extracorporeal Shockwave Therapy in Rotator Cuff Tendinopathy: A Retrospective Cohort Study

Abstract Background: Rotator cuff tendinopathy is a major cause of shoulder pain and disability. Fo- cused extracorporeal shockwave therapy (ESWT) is an established conservative treatment option; however, the predictive factors influencing the treatment response remain poorly characterized. Objectives: To identify clinical, demographic, and metabolic predictors of pain reduction and functional improvement at four months following focused ESWT in patients with supraspinatus tendinopathy, with the goal of informing individualized treatment planning and early prognostic counseling. Methods: This retrospective cohort study analyzed patients with supraspinatus tendinopathy (calcific and non-calcific) treated with focused ESWT at a university rehabilitation center between June 2020 and December 2025. Outcomes were assessed at baseline and 4-month follow-up using the Visual Analog Scale (VAS), Roles and Maudsley, and Constant–Murley scores. Change score analysis with covariate adjustment and backward stepwise selection were performed to identify predictors of clinical improvement. Results: A total of 239 patients (97 males [40.6%], 142 females [59.4%]; mean age 60.2 ± 11.5 years; mean BMI 25.5 ± 4.0 kg/m 2 ) were included, of whom 101 (42.3%) had calcific tendinopathy. Significant improvements were observed in all outcomes: VAS decreased from 6.50 ± 1.35 to 3.96 ± 2.09 (p < 0.001; Cohen’s d = 1.24), and Constant–Murley score increased from 60.38 ± 14.53 to 75.88 ± 15.52 (p < 0.001; Cohen’s d = 1.07). Patient-reported satisfaction (Roles and Maudsley score) showed a 91.2% success rate (excellent or good outcomes). Regression analysis identified baseline severity as the strongest predictor of improvement in all models. BMI emerged as a significant predictor of functional recovery (β = −0.95, p < 0.001 for Constant–Murley change), with each 1 kg/m 2 increase associated with approximately 1-point less improvement. Conclusions: Baseline clinical severity and body mass index were consistent predictors of ESWT effectiveness in rotator cuff tendinopathy. A lower BMI was associated with greater functional improvement, highlighting a potentially modifiable factor for treatment optimization. These findings support personalized treatment planning and early prognostic counseling in clinical practices.