The Gluteal Region. 313 



behind this, is the lateral cutaneous branch of the ilio- 

 hypogastric ; between the latter and the posterior superior 

 spine are lateral branches from the posterior divisions of 

 the three upper lumbar nerves. Between the posterior in- 

 ferior spine and the ischial spine are branches from the 

 posterior divisions of the three upper sacral nerves. Be- 

 tween the ischial spine and the tuberosity of the ischium 

 is the perforating cutaneous branch of the fourth sacral 

 nerve, and, lastly, external to the tuberosity, are branches 

 of the small sciatic curving upwards over the lower bor- 

 der of the gluteus maximus. The superior gluteal nerve 

 is situated immediately below the landmark for the gluteal 

 artery; the small sciatic and the inferior gluteal are 

 about half an inch external to the landmark for the pudic 

 artery, i.e., the spine of the ischium, while the great sciatic 

 lies about one inch external to the same landmark, and 

 may be represented by a line drawn downwards from this 

 point, or from a point, a little internal to the middle of the 

 space between the tuber ischii and the great trochanter, to 

 the middle of the lower part of the back of the thigh. 



