COMPARING EXERCISES WITH AND WITHOUT ELECTROMYOGRAPHIC BIOFEEDBACK IN SUBACROMIAL PAIN SYNDROME: A RANDOMIZED BLIND STUDY.
Exercise Therapy, Electromyography, Scapula, Shoulder Impingement Syndrome, Shoulder Pain
Background: Changes in movement and muscle activation of scapulohumeral joint are related to Subacromial Pain Syndrome. Electromyography biofeedback during exercise may enhance muscle activation and coordination, and consequently improve pain and shoulder function.
Methods: This study compared the effects of an exercise protocol with and without using electromyographic biofeedback on pain, function and movement of the shoulder complex in subjects with Subacromial Pain Syndrome. A total of 24 volunteers of both genders were randomized into the therapeutic exercises and Biofeedback groups in the trapezius and serratus muscles. Pain and shoulder function were evaluated as the primary outcome and range of motion, muscle strength, electromyographic activity and scapulohumeral kinematics as secondary outcomes. The subjects underwent eight weeks of intervention and comparisons were made between groups in baseline, at 4 weeks, 8 weeks, and at 4 weeks post intervention.
Findings: There were no differences between groups for pain (p= 0.11; CI: -1.57 to 0.41) and shoulder function (p = 0.33; CI: - 6.89 to 11.33), muscle strength, range of motion, and electromyographic variables. Significant differences were observed in upward scapular rotation at 60° of arm elevation (P = 0.006; CI: 0.9 to 9.3) in the Biofeedback group. There was no difference for the other variables of scapular kinematics.
Interpretation: Therapeutic exercises have been shown to be effective in reducing pain and improving function in patients with SPS. The addition of EMG-biofeedback to exercise protocols did not influence the analyzed variables.