im 



THE ARTIcrLATfOyS 



In the ilorsal vedon it is a round slendtT ronl which is put on the stretoli in 

 flexion and n-hwni in extension of the hack. 



The ligamentum nuchse, or the posterior cervical ligament ( liii. 204), is the 

 continuation in the neck of the supraspinous li.uanient, from which, however, it 

 differs considerably. It is a slender vertical septum of an elongated triangular 

 form, extending from the seventh cervical vertebra to the external protuberance 

 and the crest of the occipital bone. Its anterior border is firmly attached to the 

 tijis of the s|)ines of all the cervical vertelirae, including the posterior tul)ercle of tbc 

 atlas, as well as to the occiput. Its posterior border gives origin to the trapezii, 

 with the tendinous til ires c)f which muscles it blends. Its lateral, triangular sur- 



Fio. 204. — Side View ok Ligamextum Nuch.e. 



Ligamentum nuchae 

 First interspinalis muscle 



faces afford numerous ]ioints of attachment for the ]iosterior muscles of the head 

 and neck. 



In man it is rudimentary, and consists of elastic and white fil)rous tissues. As 

 seen in the horse, elephant, ox, and other mammiferous quadrupeds, it is a great 

 and im])ortant elastic ligament, wdiich even reaches along the dorsal part of the 

 spinal column. In these animals it serves to support the head and neck, which 

 otherwise from their own weight would hang down. Its rudimentary state in man 

 is the direct consequence of his erect position. 



The interspinous ligaments (fig. 205) are thin membranous structures Avliicli 

 extend l)et\vccn the spines, and are connected with the ligamenta su])tlava in front. 

 and the sui>ras])inous ligament l)ehind. The fibres pass oblicjuely from the root of 

 one spine to the ti]) of the next; they thus decussate. They are best marked in the 

 lum])ar region, and are replaced by the well-developed interspinales muscles in the 

 cervical retrion. 



