Effect of Motor-Control Exercises on Scapulohumeral and Scapulothoracic Muscle Activations in Athletes With Secondary Subacromial Impingement Syndrome.

Abstract

Context Unbalanced or uncoordinated activity across either the scapulohumeral or the scapulothoracic muscle may impair scapulohumeral rhythm during arm elevation. Objective To compare the effects of progressive resistance exercises (PREs), integrated with and without facilitatory motor-control exercises (MCEs), on scapulohumeral and scapulothoracic myoelectric activities in overhead athletes diagnosed with secondary subacromial impingement syndrome (SAIS). Design Randomized controlled clinical trial. Setting Neuromuscular Rehabilitation Research Center. Patients or other participants Overhead athletes diagnosed with secondary SAIS were assigned randomly to 3 parallel groups: 2 intervention groups and 1 control group. Interventions All groups received contemporary physical therapy modalities every other day for 8 weeks. Intervention groups I and II also completed scapulohumeral and scapulothoracic PREs, integrated, respectively, with and without facilitatory MCEs targeting infraspinatus and lower trapezius muscles. Main outcome measures Scapulohumeral and scapulothoracic myoelectric activities were recorded during scapular arm abduction between 80° and 110° before and after the prescribed treatment protocols. Results Scapulohumeral and scapulothoracic PREs reduced the corresponding myoelectric activities during scapular arm abduction within the groups ( P ≤ .02, partial η 2 ≥ 0.127). Facilitatory biofeedback-guided exercises integrated into PREs preserved scapulohumeral and scapulothoracic myoelectric activities ( P ≤ .03), excluding teres minor myoelectric activity ( P > .99). Conclusions Scapulohumeral and scapulothoracic PREs reduced the corresponding muscle activations during scapular arm abduction in overhead athletes with secondary SAIS. Facilitatory MCEs targeting infraspinatus and lower trapezius muscles, integrated into PREs, preserved scapulohumeral and scapulothoracic muscle activations.