Scapulothoracic motion is dependent on a force couple balance between the various periscapular muscles, enabling scapular internal and external rotation, protraction and retraction, and medial and lateral tilt.1 Dysfunction of any of the muscles can result in scapulothoracic abnormal motion, leading to an abnormal scapulohumeral rhythm (SHR) and motion of the shoulder complex.20 Scapular winging is one type of scapulothoracic abnormal motion, caused by either traumatic injury or chronic compression of either the long thoracic nerve (LTN) or spinal accessory nerve (innervating the serratus anterior (SA) and trapezius muscles, respectively).20,27 The SA plays a critical role in scapular stabilization against the chest wall, as well as scapula external rotation by pulling the scapula anterolaterally around the thorax, thereby elevating the acromion, enabling abduction and elevation of the glenohumeral joint.18 It acts as in a force couple with the rhomboids and levator scapulae in stabilizing the scapula during SHR. Therefore, a palsy or atrophy of the SA causes an internally rotated and medially prominent resting position due to unopposed pull of the rhomboid major and minor and levator scapulae; which is worsened with attempted arm elevation.8