

THE VERTEBRAL COLUMN AS A WHOLE 



115 





Posterior Surface. The posterior surface 

 of the vertebral column presents in the 

 median line the spinous processes. In the 

 cervical region (with the exception of the 

 second and seventh vertebrae) these are 

 short and horizontal, with bifid extremities. 

 In the upper part of the thoracic region 

 they are directed obliquely downward; in 

 the middle they are almost vertical, and in 

 the lower part they are nearly horizontal. 

 In the lumbar region they are nearly hori- 

 zontal. The spinous processes are separated 

 by considerable intervals in the lumbar 

 region, by narrower intervals in the neck, 

 and are closely approximated in the middle 

 of the thoracic region. Occasionally one of 

 these processes deviates a little from the 

 median line a fact to be remembered in 

 practice, as irregularities of this sort are 

 attendant also on fractures or displacements 

 of the vertebral column. On either side of 

 the spinous processes is the vertebral groove 

 formed by the laminae in the cervical and 

 lumbar regions, where it is shallow, and by 

 the lamina? and transverse processes in the 

 thoracic region, where it is deep and broad; 

 these grooves lodge the deep muscles of the 

 back. Lateral to the vertebral grooves are 

 the articular processes, and still more later- 

 ally the transverse processes. In the tho- 

 racic region, the transverse processes stand 

 backward, on a plane considerably behind 

 that of the same processes in the cervical 

 and lumbar regions. In the cervical region, 

 the transverse processes are placed in front 

 of the articular processes, lateral to the 

 pedicles and between the intervertebral 

 foramina. In the thoracic region they are 

 posterior to the pedicles, intervertebral 

 foramina, and articular processes. In the 

 lumbar region they are in front of the 

 articular processes, but behind the inter- 

 vertebral foramina. 



Lateral Surfaces. The lateral surfaces are 

 separated from the posterior surface by the 

 articular processes in the cervical and lum- 

 bar regions, and by the transverse processes 

 in the thoracic region. They present, in 

 front, the sides of the bodies of the verte- 

 brae, marked in the thoracic region by the 

 facets for articulation with the heads of 

 the ribs. More posteriorly are the inter- 

 vertebral foramina, formed by the juxta- 

 position of the vertebral notches, oval in 



1st cervical 

 or Atlas 



2nd cervical ~ 

 or Axis 



1st thoracic^ 



2-\ 



7- 



s-\ 



1st lumbar - 



Fia. 111. Lateral view of the vertebral column. 



