ARTICULATIONS OF VERTEBRAL COLUMN 



225 



4. Ribs with the vertebral column. 



5. The articulations at the front of the thorax. 



(a) Costal cartilages with the sternum. 

 (6) Costal cartilages with the ribs. 



(c) Sternal. 



(d) Certain costal cartilages with each other. 



1. THE ARTICULATIONS OF THE VERTEBRAL COLUMN 



There are two distinct sets of articulations in the vertebral column: — 



(a) Those between the bodies and intervertebral discs which form synchon- 

 droses and which are amphiarthrodial as regards movement. 

 (6) Those between the articular processes which form arthrodial joints. 



The ligaments which unite the various parts may also be divided into two 

 sets, viz. — immediate, or those that bind together parts which are in contact; 

 and intermediate, or those that bind together parts which are not in contact. 



Immediate. 



(a) Those between the bodies and discs. 

 (6) Those between the articular processes. 



Intermediate. 



(c) Those between the laminae. 



(d) Those between the spinous processes. 



(e) Those between the transverse processes. 



Fig. 264. — Horizontal Section through an Intervertebral Fibro-cartilage and 



THE Corresponding Rebs. 



Fibrous ring of intervertebral 



fibro-cartilage 



( 



Anterior radiate or 

 stellate ligament 



Capitular synovial 

 sac 



Pulpy nucleus of intervertebral 

 fibro-cartilage 



Costo-transverse synovial sac 



Tuberctilar ligament 



(a) The Articulations of the Bodies of the Vertebra 



Class. — False Synchondrosis. 

 The ligaments which unite the bodies of the vertebrae are : — 



Intervertebral fibro-cartilages. 

 Short lateral ligaments. 



Anterior longitudinal. 

 Posterior longitudinal. 



The intervertebral fibro-cartilages (figs. 260 and 264) are tough, but elastic 

 and compressible discs of composite structure, which serve as the chief bond of 

 union between the vertebrse. They are twenty-three in number, and are inter- 

 posed between the bodies of all the vertebrse from the epistropheus to the sacrum 

 (figs. 260 and 271). Similar discs are found between the segments of the sacrum 

 and coccyx in the younger stages of life, but they undergo ossification at their 

 surfaces and often throughout their whole extent. 



