THE POSTERIOR RAMI 125 



lower part of the sacra-spinalis (erector spinae) and cutaneous 

 branches to the buttock. The fourth and fifth sacral nerves 



[Photo by Alinari. 



FIG. 60. The Areas of Skin supplied by the Posterior Kami (primary 

 divisions) of the Spinal Nerves. 



NOTE. The posterior rami of C. i, 7 and 8, and L. 4 and 5, do not supply any 

 branches to the skin. 



unite with the coccygeal, and the small trunk formed in this 

 way supplies a limited area of skin over the coccyx. 



Referred pain from visceral disturbances is usually experi- 

 enced in the areas of distribution of the anterior rami, but it 



