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os hyoideum
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Hyoid bone Anterior surface Enlarged
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Anterolateral view of head and neck
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Hyoid+Bone
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A02835232409
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The ("Lingual Bone") is a
Bone in the
Human Neck , not articulated to any other bone; it is supported by the
Muscle s of the neck and in turn supports the root of the
Tongue . Its name is derived from the Greek word ''hyoeides'' meaning "shaped like the letter upsilon" (''υ''). The hyoid bone is shaped like a horseshoe, and is suspended from the tips of the
Styloid Process es of the temporal bones by the stylohyoid ligaments.
It consists of five segments: a body, two greater cornua, and two lesser cornua.
The body (''corpus oss. hyoidei'') or central part is of a quadrilateral form. Its
Anterior surface is convex and directed forward and upward.
It is crossed in its upper half by a well-marked transverse ridge with a slight downward convexity, and in many cases a vertical median ridge divides it into two lateral halves.
The portion of the vertical ridge above the transverse line is present in a majority of specimens, but the lower portion is evident only in rare cases.
The anterior surface gives insertion to the
Geniohyoid Muscle in the greater part of its extent both above and below the transverse ridge; a portion of the origin of the
Hyoglossus notches the lateral margin of the geniohyoid attachment.
Below the transverse ridge the
Mylohyoid ,
Sternohyoid , and
Omohyoid are inserted.
The
Posterior surface is smooth, concave, directed backward and downward, and separated from the
Epiglottis by the
Hyothyroid Membrane and a quantity of loose areolar tissue; a
Bursa intervenes between it and the hyothyroid membrane.
The superior border is rounded, and gives attachment to the hyothyroid membrane and some
Aponeurotic fibers of the
Genioglossus .
The inferior border affords insertion medially to the sternohyoid and laterally to the omohyoid and occasionally a portion of the
Thyrohyoid . It also gives attachment to the Levator glandulae thyreoideae, when this muscle is present.
In early life the lateral borders are connected to the greater cornua by synchondroses; after middle life usually by bony union.
The greater cornua (''cornua majora'') project backward from the lateral borders of the body; they are flattened from above downward and diminish in size from before backward; each ends in a
Tubercle to which is fixed the
Lateral Hyothyroid Ligament .
The upper surface is rough close to its lateral border, for muscular attachments: the largest of these are the origins of the
Hyoglossus and
Constrictor Pharyngis Medius which extend along the whole length of the cornu; the
Digastric Muscle and
Stylohyoid Muscle have small insertions in front of these near the junction of the body with the cornu.
To the medial border the
Hyothyroid Membrane is attached, while the anterior half of the lateral border gives insertion to the
Thyrohyoid .
The lesser cornua (''cornua minora'') are two small, conical eminences, attached by their bases to the angles of junction between the body and greater cornua.
They are connected to the body of the bone by fibrous
Tissue , and occasionally to the greater cornua by distinct diarthrodial
Joint s, which usually persist throughout life, but occasionally become
Ankylosed .
The lesser cornua are situated in the line of the transverse ridge on the body and appear to be
Morphological continuations of it.
The apex of each cornu gives attachment to the
Stylohyoid Ligament ; the Chondroglossus rises from the medial side of the base.
The hyoid is life, in the body shortly afterward, and in the lesser cornua during the first or second year after birth.
Due to its position, the hyoid bone is not usually easy to fracture in most situations. In cases of suspicious death, however, a fractured hyoid is a strong sign of
Strangulation .
