308 The Nerves and Muscles of the Leg 
group. A truly accurate determination could be made only by section- 
ing each of the various roots and each of the various nerves of distri- 
bution in various plexuses and then following the paths of degeneration. 
3. Variation in the Association of the Terminal Branches Arising from 
the Femoral Nerve. 
Soon after the femoral nerve passes under the inguinal hgament it 
gives rise to the various branches which serve to innervate the skin and 
muscles of the front of the thigh and the arteries and joints. There 
UN. cut. ant. 1 
_-N. cul. ant.2 
<. _N.cul. med. 
N. Vast.lat 
&intermed. 
/ 
N. vast. med. 
Fic. 4. Diagram to illustrate the approximate regions of the femoral nerve 
trunk occupied by the fibers which pass out into its muscular and cutaneous 
branches. The stippled area indicates the position of the main bulk of the 
fibers of the third lumbar nerve. 
is great variation in the association of the nerves going to these various 
structures. Now one set of nerves may be bound in a common trunk for 
a part of their course, now another. The association of the various nerves 
into common trunks is limited, however, to the association of contiguous 
regions shown in the diagram, Fig. 4. Two or more of these regions 
may continue for a time to be associated after the femoral trunk has 
split into branches. Thus the nerves of the rectus femoris muscle are 
often bound for a part of their course with those of the vastus lateralis 
or with those of the vastus lateralis and intermedius before the final 
division takes place. But the nerve to the rectus femoris muscle is never 
found bound up in a common trunk with the nerve to the vastus medialis 
or the saphenous nerve unless the nerves to the vastus lateralis and 
