Encyclopedia entry
Long (posterior) Thoracic Nerve (External Respiratory Nerve of Bell)
Abstract
The following variations occur in the origin of this nerve. A contribution has been reported from the fourth cervical and from the fifth cervical nerve, which may not join the main trunk of the nerve but pass directly to the upper digitations of m. serratus anterior. The root from the seventh cervical nerve may be missing. An additional root from the eighth cervical nerve has been reported. Infrequently, the long thoracic nerve does not pass through scalenus medius and the nerve trunk is formed over the first rib. Hence, the upper part may pass throught the axilla unattached to the fascia.
The following variations occur in the origin of this nerve. A contribution has been reported from the fourth cervical and from the fifth cervical nerve, which may not join the main trunk of the nerve but pass directly to the upper digitations of m. serratus anterior.
The root from the seventh cervical nerve may be missing. An additional root from the eighth cervical nerve has been reported. Infrequently, the long thoracic nerve does not pass through scalenus medius and the nerve trunk is formed over the first rib. Hence, the upper part may pass throught the axilla unattached to the fascia.
The nerve is usually formed of the fifth, sixth, and seventh cervical nerves; the first two pierce m. scalenus medius while the seventh passes in front of that muscle.

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Riferimenti dell’opera originale
Elenco riportato come compare nella fonte, senza normalizzazione dei formati bibliografici.
- Furukawa, T. (1989) External respiratory nerve of Bell (long thoracic nerve). Neurology 39:147-148.
- Hayek, H. von (1951-52) Variationsstätistische Untersuchungen über die erste Verlaufsstrecke des Nerven thoracicus longus. Anat. Anz. 98:105-115.
- Hochstetter, A von. (1986) über eine chirurgisch bedeutsame Varietät im Verlaufe des N. thoracicus longus. N. thoracicus longus, a variation of surgical interest. Anat. Anz., Jena 162:125-127.
- Schaefer, E.A., Symington, J. and T.H. Bryce, Eds., (1915) Quain's Anatomy, 11th ed., Longmans, Green, and Co., London.
Anatomical classification
- Systems:
- Nervous system
Content provenance
Adaptation
Adaptation of «Long (posterior) Thoracic Nerve (External Respiratory Nerve of Bell) — 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/LongThoracicNerve.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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