The supraclavicular nerves arise from the third and fourth cervical nerves; they emerge beneath the posterior border of the Sternocleidomastoideus, and descend in the posterior triangle of the neck beneath the platysma and deep cervical fascia. Near the clavicle they perforate the fascia and Platysma to become cutaneous, and are arranged, according to their position, into three groupsanterior, middle and posterior. The medial supraclavicular nerves or anterior supraclavicular nerves cross...