Origin: First rib
Insertion: Subclavian groove of clavicle
Artery: Thoracoacromial artery, clavicular branch
Nerve: Nerve to subclavius
Action: Depression of clavicle
The Subclavius is a small triangular muscle, placed between the clavicle and the first rib. It arises by a short, thick tendon from the first rib and its cartilage at their junction, in front of the costoclavicular ligament; the fleshy fibers proceed obliquely upward and lateralward, to be inserted into the groove on the under surface of the clavicle between the costoclavicular and conoid ligaments.
Variations.—Insertion into coracoid process instead of clavicle or into both clavicle and coracoid process. Sternoscapular fasciculus to the upper border of scapula.Sternoclavicularis from manubrium to clavicle between Pectoralis major and coracoclavicular fascia.