Effectiveness of psychologically informed physical therapy, tendon-specific exercise program and routine physical therapy in prolonged unilateral shoulder pain and symptom correlations with imaging: a single-center, randomized, parallel-group, three-

BACKGROUND: Shoulder complaints are one of the most common musculoskeletal ailments. Patient-specific characteristics such as obesity, depression and physical labor are established risk factors, whereas imaging findings are common and associations between specific imaging findings and symptomatology is limited. General exercises are considered useful in treatment whereas evidence for specific tendon exercises is lacking. Biopsychosocial model is also recommended, but has not been extensively studied concerning shoulder symptoms. This article describes the study protocol designed to evaluate the effectiveness and the cost-effectiveness of routine and specific physical therapy (PT) interventions. Imaging is performed for descriptive, longitudinal and imaging-symptom correlation studies. METHODS: The Rehabilitation of Shoulder Pain: Evaluation and Clinical Trial (RESPECT) is a randomized three-arm parallel-group study involving 300 participants aged 20 to 60 years with prolonged unilateral shoulder pain. Participants will receive either routine PT, physiotherapist-guided tendon-specific exercise program or psychologically informed PT. Bilateral shoulder radiographs, ultrasound and magnetic resonance imaging will be done at the baseline and at 12 and 36 months. Electronic surveys will be completed at the baseline and at 3, 6, 12 and 36 months. The primary outcome will be patient-specific functional scale (PSFS) at 12 months, analyzed using analysis of covariance (ANCOVA), adjusted for baseline PSFS. DISCUSSION: RESPECT will provide systematic and controlled data regarding different PT interventions in prolonged shoulder symptoms, which is currently limited. Being one of the most common sources of musculoskeletal pain, improved management could reduce symptom-related burden and prolonged functional impairment at individual and population level. CLINICALTRIALS: gov; Registration number NCT07235969; Registered November 18th, 2025; Version: 1.0.