THE FRONT OF THE THIGH 



399 



For the purpose of differential 



when the patient lies down, 

 diagnosis, the patient is 

 examined in the recumbent 

 posture, and a finger is 

 placed on the proximal part 

 of the fossa ovalis so as to 

 control the femoral vein 

 and also a femoral hernia, 

 if one is present. The 

 patient is then allowed to 

 resume the erect attitude. 

 The swelling, if venous in 

 nature, gradually reappears 

 from below as the veins fill 

 up. 



The superficial epigastric 

 and external pudendal arteries 

 have been described on p. 

 253. The superficial cir- 

 cumflex iliac pierces the deep 

 fascia lateral to the fossa 

 ovalis and passes laterally 

 (p. 409). All three are de- 

 rived from the femoral 

 artery. 



The Cutaneous Nerves which 

 supply the skin of the front of 

 the thigh arise from the lumbar 

 plexus. 



1. The lateral cutaneous (L. nerve 

 2, 3) enters the thigh behind 



the lateral extremity of the in- 

 guinal ligament, and runs behind 

 the deep fascia for two inches 

 before breaking up into anterior 

 and posterior divisions, which 

 pierce the deep fascia to supply D eal nerve 



the skin of the buttock and of (O.T. ant. tibial)" 

 the lateral aspect of the thigh as 

 far as the knee. 



2. The lumbo-inguinal nerve 

 (crural branch of the genito- crural) 

 (L. i, 2) supplies an area of skin 

 distal to the intermediate part of 



the inguinal ligament. It varies greatly in size, and sometimes extends to 

 the region of the knee. In renal colic, pain is sometimes referred to the 

 areas supplied by the lumbo- and ilio-inguinal nerves (p. 354). 



Lateral cutaneous 

 nerve of the thigh 



Ilio-inguinal nerve 

 Lumbo-inguinal - ^ 



nerve 



Branch from 

 medial cutaneous" 

 nerve of the thigh 

 Intermediate cuta- 

 neous nerve 

 of the thigh 

 Medial cutaneous- 

 nerve of the thigh 



Great saphenous 

 vein" 



Anterior part of 

 medial cutaneous- 

 nerve of the thigh 



Infrapatellar branch 

 of saphenous nerve" 



Great saphenous 

 vein" 



Saphenous nerve. 

 Superficial peroneal 



FIG. 118. The Superficial Nerves and 

 Veins on the Anterior Aspect of the 

 Lower Limb. 



