|
In anatomy, the second cervical vertebra (C2) of the spine is named the axis (from Latin ''axis'', "axle") or epistropheus. It forms the pivot upon which the first cervical vertebra (the atlas), which carries the head, rotates. The most distinctive characteristic of this bone is the strong odontoid process known as the dens which rises perpendicularly from the upper surface of the body. That peculiar feature gives to the vertebra a rarely used third name: vertebra dentata. In some judicial hangings the odontoid process may break and hit the medulla oblongata, causing death. ==Structure== The body is deeper in front than behind, and prolonged downward anteriorly so as to overlap the upper and front part of the third vertebra. It presents in front a median longitudinal ridge, separating two lateral depressions for the attachment of the ''Longus colli'' muscles. Its under surface is concave from before backward and convex from side to side. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Axis (anatomy)」の詳細全文を読む スポンサード リンク
|