Triangles of the neck - neurovasculature (Latin)

The anatomical relationships between several neurovascular structures of the neck can be appreciated from this lateral perspective. The aa. carotici ascend through the neck just deep to the v. jugularis interna. Travelling medial to the vena jugularis interna is the n. vagus (CN X). The n. accessorius (CN XI) descends posterolaterally, emerging from behind the margo posterior of the m. sternocleidomastoideus, where it receives sensory contributions from spinal nerves C3/4. Branches of the plexus cervicalis, ansa cervicalis and n. phrenicus are located deep to the m. sternocleidomastoideus. Passing beneath the tendo intermedius m. omohyoidei is the a. transversa colli which branches from the truncus thyrocervicalis to supply muscles of the neck and back. The a. suprascapularis also branches from the truncus thyrocervicalis within the fossa supraclavicularis and extends laterally to supply structures of the pectoral girdle (cingulum pectorale). Also located within this region is the pars supraclavicularis plexus brachialis, which passes between the mm. scaleni anterior et posterior (spatium interscalenum).