CHAPTER XI. 



THE SPINAL COLUMN AND BACK. 



The Pyramids of the Spine. — The spine, when viewed from 

 the front, is seen to be made up of four pyramids : (1) Cervical ; 

 (2) upper dorsal ; (3) dorso-lumbar ; (4) sacro-coccygeal (Fig. 113). 



cervical pyramid 



upper dorsal 

 sternum 



dorso-lumbar 



sacral 



Flo. 113.— Diagram of the Pyramids of the Spine. 



The bases of the two upper pyramids meet at the disc 

 between the 7th cervical and 1st dorsal vertebrae ; the bases 



