Supraclavicular nerves
The supraclavicular nerves are three cutaneous nerves that emerge as a common trunk from the cervical plexus before branching to innervate the skin over the upper chest and shoulders.
Gross anatomy
Origin
The supraclavicular nerves arise from the ventral rami of C3 and C4 spinal nerves, although they receive considerably more fibers from C4.
Course
The supraclavicular nerves emerge as a common trunk underneath the sternocleidomastoid muscle at the punctum nervosum (Erb’s point). The supraclavicular nerve descends in the posterior triangle of the neck passing underneath the platysma muscle. As it approaches the clavicle the common trunk of the supraclavicular nerves divides into three groups of descending branches: the medial supraclavicular nerve, intermediate supraclavicular nerve and lateral supraclavicular nerve.
Branches and Supply
- the medial (or anterior) supraclavicular nerve crosses obliquely and superficially over the external jugular vein to lie above the medial head of the clavicle to supply the skin as far as the median plane; the medial branch supplies filaments to the sternoclavicular joint
- the intermediate (or middle) supraclavicular nerve crosses the middle of the clavicle anteriorly and supplies the skin of the chest wall over the pectoralis major and deltoid muscles; the intermediate supraclavicular nerve communicates with the cutaneous branches of the upper intercostal nerves
- the lateral (or posterior) supraclavicular nerve crosses the lateral end of the clavicle and runs obliquely along the surface of the trapezius muscle and acromion supplying the skin of the upper and posterior aspect of the shoulder
Relations
As the medial supraclavicular nerve descends in the chest it passes superficially over the external jugular vein. Along with the other cutaneous branches of the cervical plexus the lesser occipital nerve passes posterior to the sternocleidomastoid muscle at the punctum nervosum (Erb’s point) roughly midway between the origin and insertion of the muscle.
Variant anatomy
The branching pattern of the supraclavicular nerves is highly variable with up to half of the population possessing only medial and lateral branches (i.e. no intermediate branch).
Related pathology
The supraclavicular nerves may be easily damaged during surgical approach to the clavicular shaft.