THE EXTERNAL PLANTAR NERVE. 



335 



muscles and the accessorius, and terminates in numerous branches for the following 

 muscles : all the interosseous (dorsal and plantar) except occasionally one or both 

 of those in the fourth space, the outer three lumbricales, the adductor transversus 

 and adductor obliquus hallucis. This part of the nerve also furnishes articular 

 filaments to the tarso-metatarsal, and frequently to the metatarso-phalangeal joints, 

 us well as minute perforating branches, which pass upwards through the posterior 

 ends of the intermetatarsal spaces to join the interosseous branches of the anterior 

 tibial nerve (Riidinger). 



Out of ten dissections by Brooks, the lumbricales were supplied as stated above in nine. 

 In the tenth case the first and second lumbricales received branches from both the internal and 



Fig. 218. CUTANEOUS NERVES OF OUTER SIDE OF THE 

 LEG AND FOOT. (From Sappey, after Hirschfeld 

 and Leveille. ) - 



1, external popliteal nerve ; 2, its lateral cutaneous 

 branch ; 3, pcroneal communicating branch which 

 unites with 4, the tibial communicating, in 5, the 

 external saphenous nerve ; 6, calcaneal branch of the 

 external saphenous ; 7, external dorsal digital branch 

 of the fifth toe ; 8, dorsal digital branch of the 

 fourth and fifth toes ; 9, 9, musculo-cutaneous nerve ; 

 10, 10, its two divisions ; 11, union with the external 

 saphenous ; 12, communication between its outer and 

 inner branches ; 13, anterior tibial nerve, shown by the 

 removal of a part of the muscles ; 14, its inner ter- 

 minal branch, emerging in the space between the first 

 and second toes, where it gives the collateral dorsal 

 digital branches to their adjacent sides ; 15, recurrent 

 articular nerve. 



external plantar nerves (Journ. Anat.. xxi, 575). 

 The branch of the external plantar nerve to the 

 second lumbricalis runs forwards beneath the 

 adductor transversus hallucis, and then turns 

 backwards over that muscle to reach its destina- 

 tion. Cruveilhier describes the branch to the 

 third lumbricalis as piercing- the adductor trans- 

 versus hallucis. The deep part of the external 

 plantar nerve rarely gives a branch to the outer 

 head of the flexor brevis hallucis (normal accord- 

 ing 1 to Henle and Schwalbe). 



SUMMARY OF THE INTERNAL POPLITEAL 

 NERVE. This nerve supplies all the muscles 

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

 the articulations of the kuee, ankle and foot, 

 the bones and vessels of the leg, and the in- 

 tegument of the plantar aspect of the toes, 

 the sole of the foot, and in part that of the 

 lower half of the back of the leg. 



External popliteal or peroueal nerve (n.peronceus communis]. 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) and below the head of the fibula, the nerve turns 

 round that bone and, passing between it and the peroneus longus muscle, divides 

 into the anterior tibial and the musculo-cutaneous nerves. 



BRANCHES. Some articular and cutaneous branches are derived from the external 

 popliteal nerve before its final division. 



(a) The articular branches are conducted to the outer side of the capsular liga- 

 ment of the knee-joint by the upper and lower articular arteries of that side. They 



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