THE THIGH 231 



N. Ilio-inguinalis. The ilio-inguinal nerve escapes from 

 the subcutaneous inguinal ring (O.T. ext. abdominal) in 

 company with the spermatic funiculus. Most of its branches 

 go either to the scrotum or to the labium majus, but some 

 are distributed to the skin of the adjacent part of the thigh. 



N. Lumboinguinalis (O.T. Crural branch of Genito-crural). 

 The lumbo-inguinal nerve pierces the fascia lata a little 

 way distal to the inguinal ligament, and to the lateral side 

 of the falciform margin of the fossa ovalis. It supplies a 

 limited area of skin on the proximal part of the anterior 

 aspect of the thigh. With a little care a communication 

 between this nerve and the intermediate cutaneous nerve of 

 the thigh may be made out (Fig. 106). 



N. Femoris Lateralis (O.T. External Cutaneous). The 

 lateral cutaneous nerve of the thigh is distributed on the lateral 

 area of the thigh. It pierces the fascia lata in two parts. Of 

 these, one the posterior division appears about two inches 

 distal to the anterior superior spine of the ilium, and proceeds 

 posteriorly and distally; some twigs of it may be followed to the 

 lower part of the gluteal region. The anterior division comes 

 to the surface about two inches more distally. It is the larger 

 of the two, and has a wide area of distribution. It may ex- 

 tend to the knee. Previous to its division the lateral cutaneous 

 nerve of the thigh lies in a prominent ridge of the fascia lata 

 which descends vertically from the anterior superior spine of 

 the ilium. This must be slit up to expose the nerve. 



The intermediate and medial cutaneous nerves belong to the "anterior 

 cutaneous branches of the femoral nerve," but for convenience and for the 

 purposes of more precise description, they are defined by special names. 



The intermediate cutaneous nerve of the thigh (O.T. 



middle cutaneous nerve), a branch of the femoral nerve, pierces 

 the fascia lata in the middle line of the thigh about three or 

 four inches distal to the inguinal ligament. It appears usually 

 as two branches which perforate the fascia at two points 

 a short distance from each other. Both branches extend 

 distally to the knee, which they reach on its medial aspect. 



The medial cutaneous nerve of the thigh (O.T. internal 

 cutaneous nerve\ a branch of the femoral nerve, like the 

 lateral cutaneous nerve of the thigh and the inter- 

 mediate cutaneous nerve, divides into two portions an 

 anterior and a posterior which perforate the deep fascia 

 on the medial aspect of the thigh, and at some distance 

 1156 



