The Hyoid Bone
The Hyoid bone is named from its resemblance to the Greek upsilon; it is also called the lingual bone, because it supports the tongue and gives attachment to its numerous muscles. It is a bony arch, shaped like a horseshoe, and consisting of five segments, a body, two greater cornua, and two lesser cornua. It is suspended from the tip of the styloid processes of the temporal bone by ligmentous bonds, the style hyoid ligaments.
The body (basi hyal) forms the central part of the bone, and is of a quadric-lateral form; its anterior surface, convex, directed forward and upward, and is crossed at right angles by a horizontal ridge, so that this surface is divided into four spaces or depressions. At the point of meeting of these two lines is a prominent elevation, the tuberele. The portion above the horizontal ridge is directed upward, and is sometimes described as the superior border. The anterior surface gives attachment to the Genio-hyoid in the greater part of its extent; above, to the Genio-hyo-glossus; below, to the Mylo-hyoid, Styly-hyoid, and sponeurosis of the Digastric (suprahyoid spontaneurosis); and between these to part of the Hyo-glossus. The posterior surface is smooth, concave, directed backward and downward, and separated from the epiglottis by the thyro-hyoid membrane and by a quantity of loose areolar tissue. The superior border is rounded, and gives attachment to the thyroid membrane, part of the Genio-hyo-glossi and Chondro-glossi muscles. The inferior border gives attachment, in front, to the Sterno-hyoid; behind, to the Omo hyoid and to part of the Thyro-hyoid at its junetion with the great cornu. It also gives attachment to the Lavatore glandule thyroidere when this muscle is present. The lateral surfaces after middle life are joined to the greater cornua. In early life they are connected to the cornua by eartilaginous surfaces, and held together by ligaments, and occasionally a synovial membrane is found between them.
The body (basi hyal) forms the central part of the bone, and is of a quadric-lateral form; its anterior surface, convex, directed forward and upward, and is crossed at right angles by a horizontal ridge, so that this surface is divided into four spaces or depressions. At the point of meeting of these two lines is a prominent elevation, the tuberele. The portion above the horizontal ridge is directed upward, and is sometimes described as the superior border. The anterior surface gives attachment to the Genio-hyoid in the greater part of its extent; above, to the Genio-hyo-glossus; below, to the Mylo-hyoid, Styly-hyoid, and sponeurosis of the Digastric (suprahyoid spontaneurosis); and between these to part of the Hyo-glossus. The posterior surface is smooth, concave, directed backward and downward, and separated from the epiglottis by the thyro-hyoid membrane and by a quantity of loose areolar tissue. The superior border is rounded, and gives attachment to the thyroid membrane, part of the Genio-hyo-glossi and Chondro-glossi muscles. The inferior border gives attachment, in front, to the Sterno-hyoid; behind, to the Omo hyoid and to part of the Thyro-hyoid at its junetion with the great cornu. It also gives attachment to the Lavatore glandule thyroidere when this muscle is present. The lateral surfaces after middle life are joined to the greater cornua. In early life they are connected to the cornua by eartilaginous surfaces, and held together by ligaments, and occasionally a synovial membrane is found between them.
Comments