Ansa cervicalis

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Nerve: Ansa cervicalis
Ansa cervicalis. Superior root labeled as "descending hypoglossal", Inferior root labeled as "descending cervical".
Gray's	subject #210 928
Innervates	sternohyoid muscle, sternothyroid muscle, omohyoid muscle
Dorlands/Elsevier	a_44/12138601

The ansa cervicalis (or ansa hypoglossi in older literature) is a loop of nerves that are part of the cervical plexus.

Branches from the ansa cervicalis innervate the sternohyoid muscle, sternothyroid muscle, and the inferior belly of the omohyoid muscle.

Contents 1 Roots 2 See also 3 Additional Images 4 References 5 External links

[edit] Roots

Two roots make up the ansa cervicalis.

• The superior root of the ansa cervicalis is formed by a branch of spinal nerve C1. These nerve fibers travel in the hypoglossal nerve before leaving to form the superior root. The superior root goes around the occipital artery and then descends in the carotid sheath. It sends a branch off to the superior belly of the omohyoid muscle and is then joined by the inferior root.

• The inferior root is formed by fibers from spinal nerves C2 and C3.

[edit] See also

• ansa

[edit] Additional Images

Plan of the cervical plexus.

The right brachial plexus with its short branches, viewed from in front.

Cervical plexus

[edit] References

• "Ansa cervicalis." Stedman's Medical Dictionary, 27th ed. (2000). ISBN 0-683-40007-X
• Gray's Anatomy: The Anatomical Basis of Clinical Practice. (2005). ISBN 0-443-07168-3

[edit] External links

• SUNY Figs 25:03-08
• Photo and description at tufts.edu
• Mnemonic at medicalmnemonics.com 1042

v • d • e Nerves of head and neck: the cervical plexus
superficial: (lesser occipital - greater auricular - transverse cervical - supraclavicular) - deep: (ansa cervicalis - phrenic)