Anatomy, Thorax, Medial Pectoral Nerves

Excerpt

The medial pectoral nerve, which is also known as the medial anterior thoracic nerve, arises as a branch of the medial cord of the brachial plexus with fibers originating from the eighth cervical and first thoracic nerve roots. It runs along the lower border of the pectoralis minor muscle, innervating it and also the lower half of the pectoralis major muscle through its distal branch. There may be anatomical variations where the medial pectoral nerve arises from the anterior division of the inferior trunk of the brachial plexus and less frequently from the lower trunk.