It emerges from beneath the posterior border of the sternocleidomastoid muscle, then split into multiple branches.

[1] The nerves descend in the posterior triangle of the neck beneath the platysma muscle and the deep cervical fascia.

[citation needed] Near the clavicle, the supraclavicular nerves perforate the fascia and the platysma muscle to become cutaneous.

supraclaviculares anteriores; suprasternal nerves) cross obliquely over the external jugular vein and the clavicular and sternal heads of the sternocleidomastoideus, and supply the skin as far as the middle line.

[2] A supraclavicular nerve block is useful when performing surgery on the shoulder, anaesthetising a large area of skin.