Encyclopedia entry
Ansa Cervicalis
Abstract
The ansa cervicalis may arise from the first, second and third or only from the second and third cervical nerves. The ramus descendens hypoglossi may be replaced by the vagus (CN X). When no ansa is present, the innervation of the infrahyoid muscles is by branches arising directly from C2 and C3. The nerve to the thyrohyoid may arise as a branch of the ramus descendens hypoglossi. The phrenic nerve may also receive a contribution from the descendens hypoglossi. Variable connections with the cervical sympathetic trunk have been reported.
The ansa cervicalis may arise from the first, second and third or only from the second and third cervical nerves.
The ramus descendens hypoglossi may be replaced by the vagus (CN X). When no ansa is present, the innervation of the infrahyoid muscles is by branches arising directly from C2 and C3. The nerve to the thyrohyoid may arise as a branch of the ramus descendens hypoglossi.
The phrenic nerve may also receive a contribution from the descendens hypoglossi.
Variable connections with the cervical sympathetic trunk have been reported.
Riferimenti dell’opera originale
Elenco riportato come compare nella fonte, senza normalizzazione dei formati bibliografici.
- Langsam, C.L.M (1941) Omohyoideus in American Whites and Negroes. Am. J. Phys. Anthropol. 28:249-259.
- Lippmann, R. von (1910) Abnormer Ursprung des Ramus descendens N. hypoglossi aus dem N. vagus. Anat. Anz. 37:1-4.
- Rodrigues, A. (1930) Le descendens cervicalis chez l'homme et chez le mammifères (quelques notes sur son évolution phylogénique). Assoc. Anatomistes Comptes Rendus 25:267-282.
- Schaefer, E.A., Symington, J. and T.H. Bryce., Eds. (1915) Quain's Anatomy, 11th ed., Longmans, Green, and Co., London.
- Turner, W. (1893) A phrenic nerve receiving a root of origin from the descendens hypoglossi. J. Anat. Physiol. 27:427.
- Winckler, G. (1955) A propros des relations que relations que existent entre le plexus cervical et le nerf grand hypoglosse. Assoc. Anatomistes Comptes Rendus 42:1415-1419.
- Wischnewsky, A.S. (1930) Die Aufbautypen des Ramus descendens nervi hypoglossi. Z. Anat. Entwicklundsgeschichte 92:551-564.
Anatomical classification
- Systems:
- Nervous system
Content provenance
Adaptation
Adaptation of «Ansa Cervicalis — Illustrated Encyclopedia of Human Anatomic Variation: Opus I: Muscular System» by Ronald A. Bergman, Adel K. Afifi, Ryosuke Miyauchi. Source: https://www.anatomyatlases.org/AnatomicVariants/NervousSystem/Text/AnsaCervicalis.shtml Original work distributed under the CC BY-NC-SA 4.0 licence (https://creativecommons.org/licenses/by-nc-sa/4.0/deed.it). Adaptation by Redazione AIVA. Changes from the original: Testo originale inglese riprodotto integralmente e riorganizzato nel formato scheda del portale (sintesi, testo, riferimenti), senza modificarne le affermazioni. La traduzione italiana non è ancora stata eseguita, e la pagina lo dichiara. Le figure non sono state copiate: sono collegate alla pagina d’origine. This publication is not approved or endorsed by the authors of the original work.
Licence
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