Impact of Proximal Motor Control Exercise on Scapular Muscles Activation Pattern in Breast Cancer Survivors Following Mastectomy

This prospective, single-center, assessor-blinded, parallel-group randomized controlled trial investigated whether adding proximal motor control exercises (PMCE) to conventional physiotherapy treatment (CPT) improved shoulder function and scapular muscle activation in women with post-mastectomy shoulder dysfunction. Women aged 35-55 years were randomly allocated to receive either PMCE plus CPT or CPT alone. Both groups attended supervised physiotherapy sessions three times weekly for 6 weeks. Outcomes were assessed at baseline, immediately after treatment, and at 12-week follow-up. The primary outcome was scapular and shoulder muscle activation assessed using surface electromyography (SEMG), while secondary outcomes included shoulder pain and disability assessed using the Shoulder Pain and Disability Index (SPADI).

Inclusion Criteria: Had stage I-III unilateral breast cancer. Had undergone simple or modified radical mastectomy at least 3 months before enrollment. Had achieved complete postoperative wound healing and were medically stable. Had clearance from their treating physician to participate in exercise. Presented with post-mastectomy shoulder dysfunction, defined as a SPADI score ≥30/100 and a positive Scapular Dyskinesis Test. Exclusion Criteria: Had undergone bilateral mastectomy. Had evidence of locoregional recurrence or metastatic breast cancer. Had a history of previous shoulder surgery or major shoulder trauma unrelated to breast cancer treatment. Had pre-existing shoulder disorders, including rotator cuff tears, adhesive capsulitis, or advanced glenohumeral osteoarthritis. Had neurological disorders affecting upper-limb function. Had rheumatologic diseases affecting shoulder function. Had uncontrolled diabetes mellitus or any other medical condition contraindicating exercise participation.