atlanto-occipital membrane

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an·te·ri·or at·lan·to·oc·cip·i·tal mem·brane

the fibrous layer that extends from the anterior arch of the atlas to the anterior margin of the foramen magnum of the occipital bone.

atlanto-occipital membrane

A single midline ligamentous structure that extends from the arch of the atlas to the borders of the foramen magnum.
See also: membrane


pertaining to the atlas and occiput, e.g. atlanto-occipital joint.

atlanto-occipital fusion
a congenital defect observed in calves; causes tetraplegia at birth or by two months of age.
atlanto-occipital malformation
includes hypoplasia of the odontoid process, atlanto-occipital fusion.
atlanto-occipital malformation of Arab horses
includes occipitalization of the atlas and atlantalization of the axis. It causes incoordination with a characterisitic extension of the head at birth or soon afterwards.
atlanto-occipital membrane
there are two, the dorsal and ventral, each of which connects the cranial edge of the atlas to the margin of the foramen magnum.
References in periodicals archive ?
Breathnach (2) considered that PP resulted from ossification of the atlanto-occipital membrane and the oblique ligament.
After the vertebral arteries emerge from the cervical foramina, they run along the grooves in the superior aspects of the posterior arch of the atlas and then through the posterior atlanto-occipital membrane before entering the dura (Figure).
Last (3) observed that the free border of the posterior atlanto-occipital membrane, arching over the artery and nerve is sometimes ossified and converted the groove for the vertebral artery; into a foramen.