THE SACRAL PLEXUS 



171 



On the left side, the plexus is situated posterior to the rectum, 

 and this constitutes an important relationship, for the rectum 

 (p. 283) is capable of enormous distension, so that it may com- 



FIG. 72. The Lumbar, Sacral and Pudendal Plexuses. The abdominal 

 and pelvic portions of the sympathetic trunks are also shown. 

 (TURNER'S Anatomy.} 

 7. Sciatic nerve. 8. L. V joining part of L. IV to form the lumbo-sacral cord. 



press not only the left but also the right sacral plexus. As a 

 result, the patient may have all the symptoms of sciatica, and 

 it is of great benefit to make the thorough evacuation of the 



