Ansa cervicalis

The ansa cervicalis (or ansa hypoglossi, an archaic synonym) is a component of the cervical plexus which gives muscular branches to the geniohyoid muscle of the suprahyoid group and most of the infrahyoid (strap) muscles (excluding the thyrohyoid muscle).

It lies within the carotid triangle, superficial to the carotid sheath.

Gross anatomy

  • superior root: derived from the anterior primary rami of C1
  • inferior root: derived from the anterior primary rami of C2 and C3

Note: the thyrohyoid muscle is innervated by the ventral ramus of C1 via the hypoglossal nerve rather than via the ansa cervicalis.


History and etymology

Ansa cervicalis is Latin for handle of the neck. It comes from the loop shape of the structure, which resembles a handle.