Changes in electromyographic activity of deltoid muscles in women with shoulder pain during a functional task.

Background: Shoulder pain is one of the most common complaints of patients with musculoskeletal disorders in the shoulder and is usually caused by the Subacromial Impact Syndrome. Muscle imbalances can contribute to this syndrome leading to disorders that cause changes in muscle activity. The aim of this study was to determine whether pain causes changes in the electromyographic activity of the shoulder girdle muscles during an isometric task of arm elevation in the scapular plane.