Encyclopedia entry

Zygomatic Bone

Version 1

Abstract

The foramina of the zygomatic bone that transmit branches of the zygomatic nerve are often subject to variation in number and position. A bipartite zygomatic (os japonicum or os ainoicum) has frequently been observed. The incidence in Japanese is 7%, hence the name, and in other ethnic groups 2.5-6.5%. A zygomatic bone may also be tripartite, possessing extra sutures and accessory bones.

The foramina of the zygomatic bone that transmit branches of the zygomatic nerve are often subject to variation in number and position.

A bipartite zygomatic (os japonicum or os ainoicum) has frequently been observed. The incidence in Japanese is 7%, hence the name, and in other ethnic groups 2.5-6.5%.

A zygomatic bone may also be tripartite, possessing extra sutures and accessory bones.

An orbital tubercle, in the orbital surface of the zygomatic bone and inferior to the frontozygomatic suture, provides an attachment site for the lacertus of the lateral rectus muscle (about 90% of cases - 89.12% of 285 skulls) (Whitnall). It was more developed in males than in females; no racial differences.

The zygomatic bone may or may not, with equal frequency, participate in forming the inferior orbital fissure.

A processus marginalis is found arising from the posterior edge of the facies lateralis in about 50% of skulls, and may serve as the insertion to part of the temporal fascia.

The opening of the zygomaticotemporal and zygomaticofacial canals may be increased in number.

Numerous cases have been reported in which the zygomatic bone does not contribute to the formation of the inferior orbital fissure as a result of the articulation of the greater wing of the sphenoid with the maxilla, or by the intervention of a wormian bone. The maxilla may be directly joined to the zygomatic process of the temporal bone by a dorsal extension of the zygomatic process of the maxilla. The maxillary process may articulate with the lacrimal hamulus.

Bipartite Os Zygomaticum .

Figura della scheda «Zygomatic Bone», da Anatomy Atlases

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Supernumerary Bones of the Zygomatic Arch.

Figura della scheda «Zygomatic Bone», da Anatomy Atlases

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Bipartite Os Zygomaticum

Bipartite Os Zygomaticum

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Riferimenti dell’opera originale

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

  • Ayer, A.A. and S. Ramaswamy. (1956) The marginal tubercle of the zygomatic bone. J. Anat. Soc. India 5:28-30.
  • Bhargava, K.N. and T.C. Garg. (1960) Incidence of os japonicum (bipartite zygomatic) in Madhya Pradesh skulls. J. Anat. Soc. India 9:21-22.
  • Cutore, G. (1907) Sur un os malaire biparti. Arch. Ital. Biol. 48:477.
  • DiDio, L.J.A. (1942) Observações sobre o "tuberculo orbitario" de Whitnall no ossa zigomético do Homem (compesquisas no vivo). Ann. Fac. Med. Univ. São Paulo 18:43-69.
  • DiDio, L.J.A. (1962) The presence of the eminentia orbitalis in the os zygomaticum of Hindu skulls. Anat. Rec. 142:31-39.
  • Gruber, W. (1873) Über den an der Schläfenfläche des Jochbeines gelagerten Kiefer-Schläfenbogen - Arcus maxillo-temporalis intra-juglais - beim Menschen; nebst Nachträgen zum zweigetheilten Jochbeine - Os zygomaticum bipartitum - ohne oder mit Vorkommen des Kiefer-Schläfenbogens. Arch. Anat. Physiol. Wissen. Med. 1873:208-240.
  • Gruber, W. (1873) Über supernumeräre Knochen im Jochbogen. Arch. Anat. Physiol. Wissen. Med. 1873:337-347.
  • Gruber, W. (1875) Ein Nachtrag zum Vorkommen des zweigetheilten Jochbeins - Os zygomaticum bipartitum - beim Menschen. Arch. Anat. Physiol. Wissen Med. 1875:194-201.
  • Gruber, W. (1876) Ein Nachtrag zum Vorkommen des zweigetheilten Jochbeines - Os zygomaticum bipartitum -, bei Anwesenheit des Kiefer-Schläfenbogens - Arcus maxillo-temporalis intrajugalis. Arch. Anat. Physiol. Wissen. Med. 1876:230-235.
  • Gruber, W. (1877) Vierter Nachtrag zum Vorkommen des zweigetheilten Jochbeins - Os zygomaticum bepartitum - beim Menschen. Arch. Pathol. Anat. Physiol. Klin. Med. 69:381-383.
  • Gruber, W. (1879) Fümfter Nachtrag zum Vorkommen des Os zygomaticum bipartitum, und Zurückweisung des Prädicates "Os japonicum" für dasselbe. Arch. Pathol. Anat. Physiol. Klin. Med. 77:113-123.
  • Jeyasingh, P., Gupta, C.D., Arora, A.K. and S.K. Saxena. (1982) Study of os japonicum in Uttar Pradesh crania. Anat. Anz. 152:27-30.
  • Luschka, H. von. (1869) Der Processus marginalis des menschlichen Jochbeines. Arch. Anat. Physiol. Wissen. Med. 1869:326-330.
  • Marro, G. (1907) Contribution à la casuistique et la interprétation des anomalies de l'arcade zygomatique. Arch. Ital. Biol. 47:476-477.
  • Marro, G. (1907) Sur la division de l'os malaire. Arch. Ital. Biol. 47:477.
  • Matiegka, H. (1899) Über das "Os malare bipartitum." Anat. Anz. 16:546-557.
  • Nicola, B. (1903) Sur la suture zygomatico-frontalis. Arch. Ital. Biol. 40:313-314.
  • Nicola, B. (1905) Sur la suture zygomatico-frontalis. Arch. Ital. Biol. 43:315-316.
  • Nicola, B. (1907) Division verticale totale de l'os zygomaticum. Arch. Ital. Biol. 47:478.
  • Oertel, O. (1929-30) Zur Frage des Os interzygomaticum. Anat. Anz. 68:495-497.
  • Romiti, G. (1899) Une observation d'arc maxillo-temporal sous-jugal et sur la genèse de la bipartition de l'os malaire chez l'homme. Arch. Ital. Biol. 11:420-421.
  • Romiti, G. (1895) Sur l'inachèvement de l'arc zygomatique dan un crâne humain remarquable par d'autres variétés. Arch. Ital. Biol. 23:99.
  • Soenen, R. (1930) Zwei bisher nicht veröffentlichte Fälle von "Os malare bipartitum" aus der Anthropologischen Sammlung des Anatomischen Institutes in Bonn. Anat. Anz. 70:320-324.
  • Tsusaki, T. (1922) Über das Jochbein der einigeborenen Formosaner (Seiban). Folia Anat. Jpn. 1:217-241.
  • Whitnall, S.E. (1932) The Anatomy of the Human Orbit and Accessory Organs of Vision. Oxford, London and New York.

Anatomical classification

Systems:
Skeletal system

Content provenance

Translation

Italian translation of «Zygomatic Bone — 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/SkeletalSystem/Text/ZygomaticBone.shtml Original work distributed under the CC BY-NC-SA 4.0 licence (https://creativecommons.org/licenses/by-nc-sa/4.0/deed.it). Translation by Redazione AIVA. Changes from the original: Traduzione italiana del testo originale inglese, che resta consultabile nella versione inglese di questa pagina. Il contenuto è stato riorganizzato nel formato scheda del portale (sintesi, testo, riferimenti) senza modificarne le affermazioni. 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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