74 ANATOMY OF THE HEAD' AND NECK. 



cles; it will then be seen lying in the canal of the trans 

 verse processes of all the cervical vertebrae, except th< 

 seventh; after emerging from the atlas, it winds round ii 

 articular process, and, piercing the posterior occipit< 

 atloid ligament as well as the dura mater, enters the fora- 

 men magnum. Its small offsets to the spinal membranes 

 can now be seen at their origin. 



LIGAMENTS OF THE FIRST TWO VERTEBRA. 



The cervical vertebrae are connected with each other by 

 ligaments similar to those of the rest of the vertebrae, 

 which are described in Part Second, Dissection X. The 

 two upper vertebrae are, however, connected by special 

 ligaments with each other, and with the occipital bone. 



The removal of all the muscles, and other extraneous tissues about 

 the base of the skull and the upper part of the vertebral column, will 

 be necessary to expose these articulations. 



The OCCIPITO-ATLOID ARTICULATION is maintained by 

 two ligaments. The anterior occipito-atloid ligament con- 

 sists of a rounded cord attached above to the basilar pro- 

 cess of the occipital bone, and below to the anterior 

 tubercle of the atlas ; beneath this is a broad membrane, 

 extending from the anterior margin of the foramen mag- 

 num to the anterior arch of the atlas ; this latter is some- 

 times described separately as the deep anterior ligament. 

 The posterior occipito-atloid ligament extends from the pos- 

 terior margin of the foramen magnum to the posterior arch 

 of the atlas ; it is perforated by the vertebral arteries and 

 by the sub-occipital nerve. Lateral ligaments, consisting of 

 stout fibrous bands, extend from the bases of the transverse 

 processes of the atlas to the jugular processes of the occi- 

 pital bone ; capsular ligaments surround the articulation of 

 the condyles of the occipital bone with the articulating sur- 

 faces of the atlas, and the articulation of the atlas and axis 

 is similarly provided. 



The ATLO-AXOIDEAN ARTICULATION is maintained exter- 

 nally by a thin membrane, which unites the bodies of the 

 atlas and axis anteriorly, and their arches posteriorly. 



To see the ligaments inside the spinal canal, the posterior arches of 

 the atlas and axis must be cut away, as well as the occipital bone so 

 far as it forms the posterior half of the foramen magnum ; the dura 

 mater is to be removed. 



