Effects of Vibration Therapy on Muscle Strength, Shoulder Range of Motion, and Muscle Biomechanical Properties in Patients with Breast Cancer Undergoing Radiotherapy: A Randomized Controlled Trial

Abstract

Abstract Objective To investigate the effects of vibration therapy to home-based exercises on shoulder muscle strength, range of motion (ROM), pain-related disability, and muscles viscoelastic properties of shoulder and neck in patients with breast cancer undergoing radiotherapy. Design In this randomized controlled superiority trial was conducted with 38 participants who underwent breast cancer surgery. All patients were randomized into two groups: control group (CG) and vibration group (VG). Both groups performed home-based exercises for 5 days a week for 6 weeks. VG recived additional vibration therapy for 2 days a week for 6 weeks. Shoulder ROM, muscle strength, pain, disability, grip stength, and viscoelastic properties of the pectoralis major, upper trapezius, and sternocleidomastoid were compared pre- and post-intervention. Results VG demonstrated better improvement in shoulder ROM, muscle strength and pain-related disability (p < 0.05), except for internal rotation ROM. Only tone of pectoralis major was significantly higher in VG according to group x time interaction (p < 0.05), no differences were detected in terms of muscle viscoelastic properties in the CG patients (p > 0.05). Conclusion Vibration therapy provided superior improvements in muscle strength, ROM, and pain-related disability compared to home-based exercises alone in patients with breast cancer undergoing radiotherapy in the early postoperative phase.