Clinical Effects of Transcutaneous Vagus Nerve Stimulation in the Treatment of Frozen Shoulder: A Randomized Controlled Trial
The goal of this clinical trial is to learn if the addition of transcutaneous vagus nerve stimulation (tVNS) to exercise is effective in improving pain, shoulder function, shoulder range of motion, and psychological factors in adults with frozen shoulder. The main questions this study aims to answer are: Does adding tVNS to exercise reduce shoulder pain ? Does adding tVNS to exercise improve shoulder function and shoulder range of motion? Does adding tVNS to exercise improve psychological factors ? Does adding tVNS to exercise improve patient satisfaction? Researchers will compare the effect of active tVNS added to exercise with sham-controlled tVNS added to exercise to determine whether adding tVNS provides additional benefits in the management of frozen shoulder. Participants will: Receive active tVNS plus exercise therapy or sham-controlled tVNS plus exercise therapy. Attend supervised rehabilitation sessions 3 times per week for 6 weeks. Perform a home exercise program as instructed by the study physiotherapist.
• Age between 40 and 65 years.
• Less than 50% range of motion compared with the contralateral shoulder in at least one movement (external rotation, abduction, flexion, or internal rotation).
• More than 25% loss of range of motion in at least two movement planes compared with the unaffected shoulder.
• Increasing limitation of glenohumeral external and internal rotation during abduction from 45° to 90°.
• Shoulder pain lasting at least 3 months during activities of daily living.