Corpus: Deep cervical ansa: Unterschied zwischen den Versionen

The deep cervical ansa is a nerve loop formed by a superior radix from the C1 and C2 segments and an inferior radix from the C2 and C3 segments of the cervical plexus.

The cervical profunda innervates the entire infrahyal musculature via its nerve branches:

• thyrohyoid muscle
• sternohyoid muscle
• sternothyroid muscle
• omohyoid muscle

Some fibres of the superior radix reach the thyrohyoid muscle via the hypoglossal nerve as the thyrohyoid ramus. In addition, the superior radix is the only suprahyoid muscle that supplies the geniohyoid muscle.

The cervicalis profunda lies below the sternocleidomastoid muscle and crosses the internal jugular vein and the anterior scalene muscle in its course.

In the trigonum caroticum, the fibres of the radix superior run a short distance with the hypoglossal nerve as the "ramus descendens nervi hypoglossi", but without exchanging fibres with it ("ansa hypoglossi").

The fibres of the inferior radix run medially along the side of the phrenic nerve as the descending cervical nerve. The superior and inferior radix bundle together below the intermediate tendons of the omohyoid muscle to form the cervical sinus.

The superficial cervical superficialis lies on the sternocleidomastoid muscle and below the platysma.