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part 



CHAPTER XXIY. 



THE SPINE, 



THE vertebral column combines in a remarkable 

 way many very different and complicated functions. 

 It acts as the central pillar of the body, and as the 

 column that supports the weight of the head. It 

 connects the upper and lower segments of the trunk. 

 It gives attachments to the ribs. It has the property 

 of mitigating the effects of shocks that are transmitted 

 from various parts of the body. It permits, to a 

 wonderful degree, of a number of most complicated 

 movements ; and, lastly, forms a solid tube for the 

 reception of the spinal cord. 



It owes much of its elasticity, and of its power 

 of breaking up divers forces communicated to it, to 

 its curves, which are most fully developed in adult 

 life. At the time of birth these curvatures do not exist, 

 and the infant's spine is straight. As the child begins 

 to sit and stand and walk, and throw, indeed, increas- 

 ing responsibility upon the column in the matter of 

 supporting weight, the curves begin to form. The 

 only marked curve seen in the back of the young child 

 is a general curving of the column backwards a 

 cyphosis. When the infant is first encouraged to sit 

 erect, this is the outline assumed by the spine, and in 

 some weakly children, and especially in those afflicted 

 with rickets, this curvature is often very pronounced. 

 GG 



