<00 



THE ANATOMY OF TIIK 1IOR8E 



lalonil bonier of the arcli of tho :itlas, and are attaclicJ to the s.ides of th) 

 condyles of the oceiput, or rather between the condyles and the styloM 

 processes. 



Th: f(»n/ 'ittferior llijameiit arises from the tubercle on the inferior surface 

 of the atlas, and is attached to the basilar process of the occiput. 



The short iiifir'wr lujamcnt arises from tlie tubercle on the inferior surface 

 of the atlas, is attached to the foramen magnum of the occiput, and is con- 

 necte<l with the theca vertebralis. 



A thin fibrous ligament (the occipito-atlo'ul) surrounds the entire articular 

 tion ; it is attached anteriorly to the condyles of the 

 occiput, and posteriorly to the articulatory surface of 

 the atlas. This membrane is thin and clastic in- 

 feriorlv ; superiorly it is formed of two bundles of 

 librt's which cross one another like the letter X. 

 Internally it is lined by synovial membrane. 



Tin: AXIS, OR VKHTEBRA DEXTATA, is united to the 

 atlas, and partially also to the occiput, as follows : — 



1. Articular surfaces are formed on the odontoid 

 process of the axis, and also on the sides of its body 

 close to the root of that part. These correspond 

 with similar faces on the inside of the ring of the 

 atlas, and also on its posterior side. 



2. The lifjaments connecting the rings of the ticn 

 verti'f>r(r together, or the superior and inferior atJo 

 axoid ligaments. The former represent the inter- 

 spinous ligaments of the other vertebrse — being yellow, 

 el.istic, and formed of two laN'ers, which are con- 

 tinuous with the capsular ligaments — the latter is a 

 large thin band, which is stretched from the inferior 

 face of the axis to the inferior spine of the atlas, 

 lying concealed by the longus colli muscle. Besides 

 these two ligaments, there is also a capsular liga- 

 ment, which commences from the sides of the 

 superior atlo-axoid ligament, and after uniting with 

 the Ixtrders of the odontoid ligament is confounded 

 with the fibres (tf the inferior atlo-axoid. In fact, 

 it is a mesh of white fibrous tissue connecting the 

 three together. 



3. The odontoid ligaments, which are covered by 

 the superior atlo-axoid ligament. On cutting through 

 these the following sets of fibres will be made apparent : — First, a transverse 

 Iwind arises from the root of the odontoid process, and dividing into two like 

 the letter V, is attached on each side to the ridge on the inferior part of the 

 ring of the at-l.-is, a few thin fibres passing on to be attached to the basilar 

 (iroces-s and cond_vles of the occiput, .iecondh/, a strong band arises from 

 the point of the odontoid process, and is attached to the middle of the ridge 

 on tlic inferior part of the atlas. Thirdly, a few fibres pass across from the 

 inside of the ring of the atlas on one side to the corresponding part of tho 

 Dther. These serve to strengthen the capsule, but the y hav.i not the sub- 

 itanct) of the corresponding liiramenl in th ; hunir-,n fim lo. 



Fio. 30. — SfPERiOR View of 

 THE Joists formep be- 

 tween THE Fiu.st Two 



VeKTEBR.C of THE XECK 

 AXD BETWEEN* THE ATLAS 

 ANT) OCCIPCT. 



.\. Superior fibres of the occi- 



pito-atloid ligament, 

 r.. Atlas. 

 C Vert«bm dontita, showing 



the sui'orior atlo-nxoid 



lipaniPiit. 

 T1. Thinl n-rvii-al vertobra, 

 I'. 1'. Transverse prcoessea 



of dentata. 

 1. 1. Odontoid ligament. 



