212 Disease of Spine 



no messages can proceed from the brain to the muscles which are sup- 

 plied by nerves coming off below the injured spot ; sensation also is 



lost (seep. 216). And 

 the trophic influence 

 for the skin being lost, 

 bed-sores are very apt 

 to appear. The pa- 

 tient, therefore, with 

 a broken back, is 

 placed upon a water- 

 bed, so that the weight 

 of his body may be 

 distributed evenly, 

 and not fall upon the 

 prominent parts only. 

 The bladder and the 

 lower bowel do not 

 work properly, be- 

 cause the reflex centre 

 (p. 218) is cut off from 

 cerebral control, and 

 retention of urine and 



Fracture of spine ; cord lacerated. (A. SHAW.) . . . ,. 



cystitis probably occur, 



possibly the man has priapism (p. 216), and the reflexes, as explained 

 on page 219, are most likely exaggerated. The least touch upon the sole 

 may cause violent contractions in the quadriceps extensor ; but if the 

 displacement disorganise the lumbar enlargement these reflexes are 

 then lost, for the chain is broken. They may be lost too for a while 



when the grey matter 

 has exhausted its 

 energy by frequent 

 discharges. 



The spinal veins 

 consist of a ladder- 

 like network about 

 the neural arches of 

 the vertebrae ; of 

 anterior longitudinal 

 veins, which lie be- 

 hind the bodies and 

 receive the venae 

 basis vertebrae ; of 

 posterior longitudi- 

 nal veins, which are 

 also outside the dura mater, and which extend along the back of the cord; 

 and, lastly, of the veins of the cord itself, which pierce the dura mater, 



