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lie adjacent to the limb. Thus anteriorly we find that at least one, 

 usually two, spinal nerves give origin to branches which supply in 

 part the abdominal wall, in part the skin of the leg; and so too, 

 posteriorly we find one or two nerves supplying in part the thigh, in 

 part the ano-pudic region. In origin and in distribution these nerves 

 are more or less intimately associated with the true nerves of the 

 limb and may properly be called "border" nerves, a term applied by 

 RuGE to those nerves that supply the region where the thigh adjoins 

 the abdomen. 



We shall consider here briefly the relations of these border nerves 

 to the plexus, reserving for future consideration a treatment of their 

 variations in peripheral distribution. 



These border nerves may be divided into three groups, an anterior 

 set, a posterior set and a dorsal set. We shall consider these in the 

 order named. 



1. The Anterior Border Nerves. 



Between the most distal abdominal nerves, the supply of which 

 is confined to the abdomen and the most proximal nerve of the limb, 

 there intervene in man several nerves, mainly cutaneous, for the supply 

 of the anterior ventro-lateral border region of the abdomen and thigh. 

 These are the hypogastric, iliac, inguinal, genital and crural nerves. 

 In considering these nerves, however, it is convenient to take note at 

 the same time of the last true abdominal nerve and of the lateral 

 cutaneous nerve of the thigh, which, though it is to be considered as 

 belonging to the femoral nerve, often arises independently and in any 

 case is the most anterior of the branches of the femoral nerve and 

 of the true nerves of the thigh. 



The last true abdominal nerve may be defined as the most 

 distal nerve which supplies the rectus abdominis muscle. The 

 hypogastric nerve supplies the transverse and obhque musculature 

 of the abdomen and the skin in the hypogastric region. The iliac 

 nerve, often a lateral branch of the hypogastric, supplies the hip 

 region above the great trochanter. The inguinal nerve, like the 

 hypogastric, pierces the transversalis muscle above the iliac crest. It 

 then courses forward between the transversalis muscle and the 

 internal oblique and between the oblique muscles, or their 

 fascia, to the external abdominal ring. Here part of the fibres pass 

 down with the cord to the deeper structures of the scrotum and part 

 pass out through the external ring to supply the region where abdomen, 

 thigh and scrotum adjoin. The genital and crural nerves take a 



