ARTICULATIONS OF THE VERTEBRA. 459 



occiput, are three, the middle straight and two moderator 

 ligaments. The middle straight ligament^ called occipito- 

 axoid or apparatus ligamentosus colli, consists of a broad, 

 thick hand of fibres which extend from the cuneiform pro- 

 cess, forming the foramen magnum, to the summit of the 

 odontoid process, and pass on behind this process to be at- 

 tached to the superior central FIG. 136. 

 portion of the transverse liga- 

 ment of the atlas and still 

 lower down into the body of the 

 second vertebra and into the 

 bodies of the third* and fourth, 

 where they are Continuous with 

 the posterior common ligament. 



The moderator or oblique ligaments, (Fig. 136,) called also 

 the lateral alar or check ligaments, extend from each side of 

 the odontoid process obliquely, upward and outward, to be 

 attached above to the inner edge of each condyle. 



Tnese ligaments are short, thick, and strong, and limit 

 the extent of rotation. They have in front the anterior 

 occipito-atlantal ligaments and some cellular tissue, and 

 behind the middle straight ligament. 



3. Articulation of the atlas with the axis or dentata. The 

 ligaments of this articulation are five, (Fig. 136.) The 

 transverse, anterior and posterior atlanto-axoid, and two 

 capsular. 



The transverse is situated behind the odontoid process, 

 crossing the area of the atlas from the inner edge of the 

 oblique process on the one side, to the same point on the 

 opposite. It is a strong, thick, ligamentousband, concave, 

 and smooth anteriorly, having a synovial membrane, and 

 connected at this point with the odontoid process, forming 

 a joint. At its centre, behind the process, some of its fibres 

 ascend to join the middle straight ligament, and others 



FIG. 136 represents the ligaments which unite the atlas and dentata with the 

 occiput. 1 Posterior vertebral ligament, its upper portion. 2 Transverse 

 ligament. 3 4 Appendices of transverse ligament. 5 Moderator or check 

 ligament. 6 7 Capsular ligaments. 



X. 



