The Spine. 491 



and on the inner sides of the hands, forearms and arms. 

 In a lesion at the level of the seventh cervical, the anaes- 

 thesia affects, in addition, the radial sides of the hands, 

 forearms and arms. At the fifth and sixth cervical, the 

 anaesthesia extends to tine back of >tbe slhioulder and arms 

 in addition to the above. If at the second, third and fourth 

 cervical, the entire surface of the neck and upper part of 

 the shoulder will be affected. 



Fractures and Dislocations. Dislocation of the 

 atlas or axis is, as a rule, rapidly fatal, owing to compres- 

 sion of the cord between the posterior arch of the atlas and 

 the odontoid process of the axis. The dislocation may 

 be produced by a twisting of the neck, whereby the check 

 ligament, first, and then the transverse and other liga- 

 ments are ruptured and the atlas displaced forwards on 

 the axis. In children, traction o<f the head, combined with 

 rotation, is dangerous, since, in young people, the odon- 

 toid process is incompletely developed, and, hence, might 

 slip beneath the transverse ligament and permit disloca- 

 tion. When the cord is crushed at the first or second 

 cervical vertebra, death is usually instantaneous ; when at 

 the third, fourth or fifth, death soon occurs from injury 

 to the phrenic, but when below the fifth, breathing may 

 still be carried on by the action of this nerve. 



Operations. Spinal Drainage. For drainage pur- 

 poses, in cases of increased intra-cranial pressure, the 

 spinal membranes may be punctured, as done by Quincke 

 (1893), who inserted the needle between the third and 

 fourth lumbar vertebrae, and, therefore, below the spinal 

 cord. The depth of the puncture necessary to reach the 

 membrane in infants is about four-fifths of an inch, 

 whereas, in adults, it is about two inches. Spinal cocaini- 

 zation was proposed and employed by Corning, of New 

 York, but was popularized by Tuffer at the Thirteenth In- 



