pectoralnerver

The pectoral nerves are a pair of nerves that arise from the brachial plexus and innervate the pectoral muscles. There are two pectoral nerves: the medial pectoral nerve and the lateral pectoral nerve. These nerves are crucial for the movement and function of the chest muscles.

The lateral pectoral nerve originates from the lateral cord of the brachial plexus and typically pierces the clavipectoral fascia to supply the pectoralis major muscle. It plays a significant role in the anterior adduction and internal rotation of the arm.

The medial pectoral nerve originates from the medial cord of the brachial plexus, and often receives a communicating branch from the lateral pectoral nerve. It then passes medially, deep to the subclavian artery and vein, and then anteriorly through the pectoralis minor muscle to supply both the pectoralis minor and the sternocostal head of the pectoralis major muscle. This nerve is important for flexing, adducting, and medially rotating the arm, as well as depressing the scapula.

Together, these nerves ensure coordinated muscle activity in the chest region, contributing to arm movements and stabilization of the shoulder girdle. Injuries to the pectoral nerves can result in weakness or paralysis of the pectoral muscles, affecting the ability to perform actions such as pushing and lifting.