116 ARTHROLOGY, OR ANATOMY OF ARTICULATIONS 



denser fibers than the anterior ligament, which are similarly 

 divided into sets, and attached in a similar manner. 



The inter vertebral substances are disks of fibrocartilage placed 

 between the bodies of the vertebrae from the axis to the sacrum. 

 They vary in size and thickness in the different regions, being- 

 thicker behind than in front in the lumbar and cervical regions, 

 and uniformly thick in the dorsal region. They form about 



Fia. 20 



ANTERIOR COMMON 

 LIGAMENT. 



POSTEHIOR 

 COMMON 

 LIGAMENT. 



Vertical section of two vertebrae and their ligaments, from the lumbar region. 



one-fourth of the spinal column or one-third of the lumbar 

 region, one-fourth of the cervical and one-fifth > of the dorsal. 

 They are connected with the anterior and posterior common 

 ligaments, and in the dorsal region with the heads of ribs. 

 They are composed at the circumference of lamina 1 , ,', to 

 -V inch (J to | mm.) broad, of fibrous and fibroelastic tissue 

 and fibrocartilage arranged concentrically one within the other, 



