Nerve subclavian nerve | Latin musculus subclavius | |
 | ||
Origin first rib and cartilage Artery thoracoacromial trunk, clavicular branch Actions depression of clavicle elevation of first rib | ||
The subclavius is a small triangular muscle, placed between the clavicle and the first rib. Along with the pectoralis major and pectoralis minor muscles, the subclavius muscle makes up the anterior wall of the axilla.
Contents
Structure
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 superolaterally, to be inserted into the groove on the under surface of the clavicle.
Innervation
The nerve to subclavius (or subclavian nerve), which arises from the point of junction of the fifth and sixth cervical nerves, where is called the upper trunk of brachial plexus, innervates the muscle .
Variation
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.
Function
The subclavius depresses the shoulder, carrying it downward and forward. It draws the clavicle inferiorly as well as anteriorly.
The subclavius protects the underlying brachial plexus and subclavian vessels from a broken clavicle - the most frequently broken long bone.