Motivational Interviewing in Thoracic Outlet Syndrome

The Effect of Motivational Interviewing on Thoracic Outlet Syndrome Symptoms in Patients With Thoracic Outlet Syndrome

The goal of this clinical trial is to learn if motivational interviewing (MI) works to improve symptoms in people with thoracic outlet syndrome (TOS). TOS is a condition that causes long-term pain, numbness, and weakness in the arm and shoulder area. The main questions it aims to answer are:

• Does MI lower pain and improve arm function in people with TOS?
• Does psychological resilience predict treatment outcomes in people with TOS? Researchers will compare participants who receive MI sessions plus a home exercise program to those who receive a home exercise program alone. Participants will be randomly assigned to one of the two groups.

Participants will:

• Follow a home exercise program for 6 weeks
• Some participants will also attend up to 4 motivational interviewing sessions
• Complete questionnaires about pain, function, sleep, anxiety, and depression at the start and end of the 6-week program

This is a single-center, non-blinded (assessor-blinded), parallel-group study examining the effect of motivational interviewing (MI) as an adjunct to a standardized home exercise program in patients with thoracic outlet syndrome (TOS). Eligible participants are randomly assigned using block randomization (block size of 4) to either the experimental arm (home exercise plus MI) or the active comparator arm (home exercise alone). The randomization sequence is generated using an online randomization tool by an individual not otherwise involved in the study, ensuring allocation concealment.

MI sessions are structured around four core techniques: open-ended questioning, affirmations, reflective listening, and summarizing. Sessions proceed through engagement, agenda setting, evocation of change talk, and goal setting phases, using strategies such as exploring ambivalence, decisional balance exercises, and scaling questions to assess motivation and confidence for behavior change. Homework assignments tailored to each participant's goals may include relaxation exercises, breath awareness training, and emotion regulation strategies in addition to the standard home exercise program.

All outcome assessments are conducted by a physiotherapist who is blinded to group allocation and not otherwise involved in delivering the interventions. Assessments take place at baseline (prior to initiation of the home exercise program) and at week 6.

Inclusion Criteria:

• Diagnosis of thoracic outlet syndrome
• Age between 18 and 65 years
• Pain duration of more than 6 months
• No surgical intervention in the last 6 months

Exclusion Criteria:

• Accompanying pathologies (cervical disc problems, fibromyalgia, rotator cuff problems, diabetes, neoplastic processes)
• Unwillingness to provide informed consent