This type of lesion occurs in weakness of which muscle?
Ans. C. Serratus Anteriora. Winged scapula occurs due to damage to the serratus anterior muscle causes the deformation of the back.b. The serratus anterior muscle attaches to the medial anterior aspect of the scapula (i.e. it attaches on the side closest to the spine and runs along the side of the scapula that faces the ribcage) and normally anchor the scapula against the rib cage.c. When the serratus anterior contracts, upward rotation, abduction, and weak elevation of the scapula occurs, allowing the arm to be raised above the head.d. The long thoracic nerve innervates the serratus anterior; therefore, damage to or impingement of this nerve can result in weakening or paralysis of the muscle.e. If this occurs, the scapula may slip away from the rib cage, giving it the wing-like appearance on the upper back.f. This characteristic may particularly be seen when the affected person pushes against resistance. The person may also have limited ability to lift their arm above their head.Causes:a. The most common cause of scapular winging is anterior paralysis. This is typically caused by damage (i.e. lesions) to the long thoracic nerve.b. This nerve supplies the serratus anterior, which is located on the side of the thorax and acts to pull the scapula forward.c. Serratus anterior palsy is a dysfunction that is characteristic of traumatic, non-traumatic, and idiopathic injury to the long thoracic nerve
Deltoid
Pectoralis major
Serratus Anterior
Infra scapular
Upper Extremity