Musculus serratus anterior, commonly referred to as the serratus anterior muscle, is a superficial muscle located on the lateral surface of the thoracic region. The name "serratus" is derived from the Latin word "serratus," meaning saw-like, which reflects the appearance of this muscle's serrated or saw-toothed edge.
This muscle originates from the outer surfaces of the lower eight or nine ribs and extends anteriorly to insert into the inner border of the scapula. The serratus anterior is comprised of several slips or finger-like divisions that resemble the shape of a fan. These divisions are also known as digitations.
The serratus anterior muscle is primarily responsible for pulling the scapula forward, allowing it to rotate upward. This movement, known as scapular protraction or abduction, occurs when the arm is raised forward and upward, such as during punching or throwing motions. Additionally, the serratus anterior contributes to stabilizing and assisting in the upward rotation of the scapula, playing an important role in various shoulder movements.
This muscle is innervated by the long thoracic nerve, derived from the brachial plexus. Damage to this nerve can result in a condition called serratus anterior paralysis, which can cause weakness or winging of the scapula, leading to functional impairments in shoulder movement and stability.
Overall, the musculus serratus anterior plays a crucial role in enabling smooth and coordinated movements of the scapula, facilitating movements of the upper limb.
