The nerves of the cervical plexus and brachial plexus can be affected.
2.
One branch descends to join the cervical cutaneous nerve from the cervical plexus.
3.
The SCG also contributes to the cervical plexus.
4.
The carotid tubercle is also used as a landmark for anaesthesia of the brachial plexus and cervical plexus.
5.
The cervical plexus is formed from a unification of the anterior divisions of the upper four cervical nerves.
6.
Nerves formed from the cervical plexus innervate the back of the head, as well as some neck muscles.
7.
The anterior distribution includes the cervical plexus ( C1-C4 ) and brachial plexus ( C5-T1 ).
8.
Thus, the phrenic nerve receives innervation from parts of both the cervical plexus and the brachial plexus of nerves.
9.
The branches of the cervical plexus emerge from the posterior triangle at the nerve point, a point which lies midway on the posterior border of the sternocleidomastoid.
10.
Two sets of muscles are associated with the outer ear : the lesser and greater occipital nerves of the cervical plexus all supply sensation to parts of the outer ear and the surrounding skin.