Hyoid bone

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Bone: Hyoid bone
Hyoid bone. Anterior surface. Enlarged.
Anterolateral view of head and neck.
Latin os hyoideum
Gray's subject #45 177
Precursor 2nd and 3rd branchial arch[1]
MeSH Hyoid+Bone

The hyoid bone (Lingual Bone) (lat. Os hyoideum) is a bone in the neck, and is the only bone in the human skeleton not articulated to any other bone. It is supported by the muscles of the neck and in turn supports the root of the tongue.

The hyoid bone is shaped like a horseshoe, and is suspended from the tips of the styloid processes of the temporal bones by the stylohyoid ligaments.

Contents

[edit] Segments

It consists of five segments:

[edit] Ossification

The hyoid is ossified from six centers: two for the body, and one for each cornu. Ossification commences in the greater cornua toward the end of fetal life, in the body shortly afterward, and in the lesser cornua during the first or second year after birth.

[edit] Muscle attachments

The following muscles attach to the hyoid:[2]

[edit] Function

Though the hyoid bone is present in many mammals, its descent in living creatures is unique to Homo sapiens, allowing for the production of a wide range of sounds that other animals cannot produce.[3] It allows a wider range of tongue, pharyngeal and laryngeal movements by bracing these structures alongside each other in order to produce variation. As such, it was also present in virtually identical form in Neanderthal man. That suggests, along with other anthropological clues of communication, that the Neanderthal were capable of employing some form of spoken language.

[edit] Fracture

Due to its position, the hyoid bone is not usually easy to fracture in most situations. In cases of suspicious death, a fractured hyoid is a strong sign of strangulation.

[edit] Etymology

Its name is derived from the Greek word hyoeides meaning "shaped like the letter upsilon" (υ).

[edit] Additional images

Larynx

Head and neck of a human embryo eighteen weeks old, with Meckel’s cartilage and hyoid bar exposed.

Muscles of the pharynx and cheek.

Muscles of the neck. Lateral view.

The internal carotid and vertebral arteries. Right side.

The ligaments of the larynx. Antero-lateral view.

Sagittal section of the larynx and upper part of the trachea.

Coronal section of larynx and upper part of trachea.

The entrance to the larynx, viewed from behind.

Sagittal section of nose mouth, pharynx, and larynx.

Extrinsic muscles of the tongue. Left side.

The thyroid gland and its relations.

Front view of neck.

[edit] See also

[edit] References

  1. ^ hednk-023 — Embryology at UNC
  2. ^ Mnemonic at medicalmnemonics.com 352
  3. ^ http://www.pnas.org/cgi/content/full/100/12/6930 Descent of the larynx in chimpanzee infants

[edit] External links

This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained herein may be outdated. Please edit the article if this is the case, and feel free to remove this notice when it is no longer relevant.