Corticosteroid injection combined with a shoulder rehabilitation system for chronic rotator cuff injuries: a protocol for a randomised controlled trial

Abstract

Introduction The main clinical symptoms of patients with chronic rotator cuff injuries (CRCI) include pain and/or limitation of movement, which severely reduce the function of the shoulder joint. Local injection of corticosteroid with local anaesthetics can control the inflammatory response and effectively relieve patients’ pain in the short term. In addition, rehabilitation exercises are considered an important tool for improving shoulder function. However, due to the presence of pain or substandard execution of movements, it is often difficult for patients to achieve the desired therapeutic effect. Although there are many options for digital rehabilitation, relatively few purely conservative treatments have been used for patients with CRCI. And even fewer studies have addressed how to improve exercise accuracy in such patients. Methods and analysis This protocol comprises three phases. First, shoulder active motion data will be collected from patients with CRCI and analysed using K-means clustering to define distinct clinical rehabilitation stages based on movement patterns and biomechanical principles. The clinical stages will be validated using one-way analysis of variance (ANOVA) and cross-tabulation to evaluate interstage functional differences and clinical consistency. Second, a shoulder rehabilitation system with real-time feedback will be developed, and its usability evaluated through a pilot study incorporating the System Usability Scale, Simulator Sickness Questionnaire and semistructured interviews. Finally, a randomised controlled trial will be conducted. 60 participants will be randomly allocated to either G1 (corticosteroid injection+digital rehabilitation) or G2 (corticosteroid injection+traditionalhome rehabilitation). The primary outcome is the Constant-Murley Score. Secondary outcomes include range of motion, Numerical Rating Scales, University of California at Los Angeles Shoulder Score, movement accuracy and exercise attitude questionnaire. Between-group comparisons will use independent t-tests or Mann-Whitney U tests, and within-group changes will be analysed with repeated measures ANOVA or Friedman test, with post hoc Bonferroni-adjusted comparisons. Ethics and dissemination The protocol was approved by the Medical Ethics Committee of Gongli Hospital, Pudong New Area, Shanghai (number: GLYY1s2024-031). All participants will provide informed consent prior to enrolment. The study findings will be disseminated through publication in a peer-reviewed journal or presentations at relevant national and international academic conferences.