404 



ABDOMEN 



The following are the branches which proceed from the 

 lumbar plexus : 



' } derived frorn.stlurnba, nerve. 



N. genito-femoralis, ,, 1st and 2nd lumbar nerves. 



N. cutaneus femoris lateralis, ,, 2nd and 3rd lumbar nerves. 

 N. obturatorius, ,, 2nd, 3rd and 4th lumbar nerves. 



N. femoralis, ,, 2nd, 3rd and 4th lumbar nerves. 



Kami musculares to the quadratus lumborum and psoas major muscles ; 

 these branches arise somewhat irregularly. 



T.xn 



Quadratus 

 lumborum """ 

 Intertransverse ' 



muscles 



Quadratus _ 



lumborum 



Intertransverse 



muscles 



Quadratus L " 



lumborum 



Psoas major 



Quadratus 

 lumborum 



Psoas major 



Quadratus' 

 lumborum 



Branch to lurnbo-sacral trunk 

 Genito-fempral nerve 

 (O.T. genito-crurall 

 External spermatic nerve (O. 

 genital branch of genito-crur; 

 Lumbo-inguinal nerve (O.T. crural - 

 branch of genito-crural) 



Last thoracic nerve 



Lateral branch 

 '- Anterior branch 

 Ilio-hypogastric nerv< 



Lateral branch 

 Anterior branch 



"" Ilio-inguinal nerve 



i."" Lateral cutaneous nerve 

 of thigh (O.T. external 

 cutaneous) 



Branch to iliacus 



Femoral nerve (O.T. 

 anterior crural) 

 'Accessory obturator nerve 

 -Obturator nerve 



FIG. 187. Diagram of Lumbar Plexus. 



The manner in which the nerves spring from the plexus 

 may now be studied. The first lumbar trunk breaks up into 

 three branches, viz., the ilio-hypogastric, the ilio-inguinal, and 

 the upper root of the genito-femoral. The second^ third^ and 

 fourth lumbar trunks each divide into an anterior and a 

 posterior division. The three anterior divisions are smaller 

 than the posterior, and they unite to form the obturator nerve ; 

 the three large posterior divisions unite to form the femoral 

 nerve. But other branches come off from certain of the 



