Encyclopedia entry

Sciatic Nerve

Version 1

Abstract

A number of variations in the course and distribution of the nerve have been reported. Bifurcation into its two major divisions (common peroneal and tibial) may occur anywhere between the sacral plexus and the lower part of the thigh. The two terminal branches of the sciatic may arise directly from the sacral plexus. The division of the nerve into its terminal branches has been reported to occur below the popliteal space. The nerve to the short head of the biceps femoris sometimes arises directly from the sacral plexus.

A number of variations in the course and distribution of the nerve have been reported. Bifurcation into its two major divisions (common peroneal and tibial) may occur anywhere between the sacral plexus and the lower part of the thigh. The two terminal branches of the sciatic may arise directly from the sacral plexus. The division of the nerve into its terminal branches has been reported to occur below the popliteal space.

The nerve to the short head of the biceps femoris sometimes arises directly from the sacral plexus.

In one study of 420 limbs, the sciatic nerve passed beneath the piriformis in 87.5%, through the piriformis in 12% (peroneal division), and above piriformis in 0.5%.In another study of 138 subjects, the sciatic passed beneath the piriformis in 118 cases (85.5%), the peroneal division passed through the piriformis in 17 (12.3%), and the entire sciatic passed through the piriformis in three (2.25%).

Figura della scheda «Sciatic Nerve», da Anatomy Atlases

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Figura della scheda «Sciatic Nerve», da Anatomy Atlases

Anatomy Atlases. Image hosted by the site it comes from. Open the original page.

Figura della scheda «Sciatic Nerve», da Anatomy Atlases

Anatomy Atlases. Image hosted by the site it comes from. Open the original page.

Riferimenti dell’opera originale

Elenco riportato come compare nella fonte, senza normalizzazione dei formati bibliografici.

  • Beaton, L.E. and B.J. Anson. (1938) The relation of the sciatic nerve and of its subdivisions to the piriformis muscle. Anat. Rec. 70:1-5
  • Calori, L. (1880) Sull'alta divisione del nervo grande ischiatico considerata come differenza nazionale e sulle varietà del muscolo piriforme. Mem. R. Accad. Sci. Istituto di Bologna S. 4. 2:623-633.
  • Cutore, G. (1902) La division du grand nerf sciatique chez l'homme. Arch Ital. Biol. 37:491.
  • Féré, Ch. (18790 Note sure un point de l'anatomie du nerf sciatique. Bulletins et Mem. de la Société Anatomique de Paris LIV(2):110-112.
  • Fredericq, H. (1908) Un cas de division complète du nerf grand sciatique accompagnée d'une duplicité complète du muscle pyramidal. Assoc. Anatomistes Comptes Rendus 10:168-170.
  • Hollinshead, W.H. and J.E. Markee. (1946) The multiple innervation of limb muscles in man. J.Bone Joint Surg. 28:721-731.
  • Kopsch, F. (1908) Rauber's Lehrbuch der Anatomie des Menschen. Georg Thieme, Leipzig.
  • Kosinski, C. (1926) La valeur anthropologique des variations dans l'innervation cutanée des membres inférieurs. Assoc. Anatomistes Comptes Rendus 21:291-295.
  • Latarjet, A. (1948) Testut's Traite d'Anatomie Humaine, 9th ed., G. Doin & Cie., Paris.
  • Ming-Tsu, P'an. (1941) The relation of the sciatic nerve to the piriformis muscle in the Chinese. Am. J. Phys. Anthropol. 28:375-380.
  • Misra, B.D. (1954) The relations of the sciatic nerve to the piriformis in Indian cadavers. J. Anat. Soc. India 3:44.
  • Nizankowski, C., Slociak, J. and J. Szybejko. (1972) Variations of the course of the sciatic nerve in man. Folia Morphol. (Warsaw) 31:451-456.
  • Parsons, F.G. and A. Keith. (1896-97) Sixth annual report of the Committee of Collective Investigation of the Anatomical Society of Great Britian and Ireland. J. Anat. Physiol. 31:31-44.
  • Paterson, A.M. (1894) The origin and distribution of the nerves to the lower limb. J. Anat. Physiol. 28:84-95, 169-193.
  • Schaefer, A.E., Symington, J. and T.H. Bryce., Eds. Quain's Anatomy, 11th ed. Longmans, Green, and Co., London.
  • Sunderland, S. and E.S.R. Hughes. (1946) Metrical and non-metrical features of muscular branches of the sciatic nerve and its medial and lateral popliteal divisions. J. Comp. Neurol. 85:205-222.
  • Trotter, M. (1932) The relation of the sciatic nerve to the piriformis muscle. Anat. Rec. 52:321-323.

Anatomical classification

Systems:
Nervous system

Content provenance

Adaptation

Adaptation of «Sciatic Nerve — 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/SciaticNerve.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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