Medial pectoral nerve

The medial pectoral nerve (also known as the medial anterior thoracic nerve) is (typically) a branch of the medial cord of the brachial plexus and is derived from spinal nerve roots C8-T1. It provides motor innervation to the pectoralis minor muscle, and the lower half (sternal part) of the pectoralis major muscle. It runs along the inferior border of the pectoralis minor muscle. Damage to the medial pectoral nerve can result in inability to elevate the shoulder. (Wikipedia)