PLANTAR NERVES. PEROKEAL NERVE. 679 



to that of the second branch into two offsets for the sides of the second and third 

 toes. 



The fourth digital branch distributed to the adjacent sides of the third and fourth 

 toes, receives a communicating branch from the external plantar nerve. 



Along the sides of the toes, cutaneous and articular filaments are given from these 

 digital nerves ; and, opposite the ungual phalanx, each sends a dorsal branch to the 

 pulp beneath the nail, and then runs onto the ball of the toe, where it is distributed 

 like the nerves of the fingers. 



EXTERNAL PLANTAR NERVE. 



The external plantar nerve completes the supply of digital nerves to the 

 toes, furnishing branches to the little toe and half the fourth : it also gives a 

 deep branch of considerable size, which is distributed to several of the short 

 muscles in the sole of the foot. There is thus a great resemblance 

 between the distribution of this nerve in the foot and that of the ulnar 

 nerve in the hand. 



The external plantar nerve runs obliquely forwards towards the outer side 

 of the foot, along with the external plantar artery, between the flexor brevis 

 digitorum and the flexor accessorius, as far as the interval between the 

 former muscle and the abductor of the little toe. Here it divides into a 

 superficial and a deep branch, having previously furnished offsets to the 

 flexor accessorius and the abductor minimi diyiti. 



a. The superficial portion separates into two digital branches, which have the same 

 general arrangement as the digital branches of the internal plantar nerve. They are 

 distributed thus. 



Digital branches. One of the digital branches continues undivided, and runs 

 along the outer side of the little toe : it is smaller than the other, and pierces 

 the plantar fascia further back. The short flexor muscle of the little toe, and occa- 

 sionally one or two interosseous muscles of the fourth metatarsal space receive 

 branches from this nerve. 



The larger digital branch communicates with an offset from the internal plantar 

 nerve, and bifurcates near the cleft between the fourth and fifth toes to supply one 

 side of each. 



&. The deep or muscular branch of the external plantar nerve dips into the sole of 

 the foot with the external plantar artery, under cover of the tendons of the flexor 

 muscles and the adductor pollicis, and terminates in numerous branches for the fol- 

 lowing muscles : all the interossei (dorsal and plantar) except occasionally one or 

 both of those in the fourth space, the two outer lumbricales, the adductor pollicis, 

 and the transversalis pedis. 



Summary of the internal popliteal nerve. This nerve supplies all the 

 muscles of the back of the leg and sole of the foot, and the integument of 

 the plantar aspect of the toes, the sole of the foot, and in part that of the leg. 



EXTERNAL POPLITEAL OR PERONEAL NERVE. 



This nerve descends obliquely along the outer side of the popliteal space, 

 lying close to the biceps muscle. Continuing downwards over the outer 

 part of the gastrocnemius muscle (between it and the biceps) below the head 

 of the fibula, the nerve turns round that bone, passing between it and the 

 peroneus longus muscle, and then divides into the anterior tibial and the 

 musculo- cutaneous nerves. 



Lateral branches. Some articular and cutaneous branches are derived 

 from the external popliteal nerve before its final division. 



ARTICULAR NERVES. The articular branches are conducted to the outer 

 side of the capsular ligament of the knee-joint by the upper and lower 



