THE ANTEEIOK CRURAL NERVE. 



605 



Tlie .'iaj'foriit.i muscle receives three or four t-wigs, which arise in common with 

 the cutaneous nerves, and reach mostly the upper part of the muscle. 



The rectus muscle receives a distinct branch on its under sui'f ace. 



The nei-ve for the vastus cxfernus, of considerable size, descends with the 

 branches of the external circumflex artery towards the lower part of the muscle. 

 It gives off a long slender articular filament, which reaches the knee and pene- 

 trates the fibrous capsule of the joint. 



Fig. 3G0. 



Fig. 369. — Deep Nerves of the Anterior akd 

 Inner part op the Thigh (from Sappey after 

 Hirschfeld and Leveille) ^ 



1, anterior crural nerve ; 2, branches given to 

 the iliacus muscle ; 3, branch to the lower paii, of 

 tlie psoas ; 4, lai-ge musculo-cutaneous branches, 

 divided to show the deeper nerves ; 5 and 6, mus- 

 cular filaments from the small musculo-cutaneous ; 

 7, origin of the cutaneous branches ; 8, communi- 

 cating filament of the internal cutaneous nerves ; 

 9, branches to the rectus ; 10, branches to the 

 vastus externus ; 11, branches to the vastus inter- 

 nus ; 12, internal saphenous nei-ve ; 13, its patellar 

 branch; 14, its continuation down the leg ; 15, 

 obturator nerve ; 16, branch from the obturator 

 nerve to the adductor longus ; 17, branch to the 

 adductor brevis ; 18, branch to the gracilis ; from 

 this a filament is prolonged downwards, to unite 

 with the plexus formed by the union of branches 

 from the internal cutaneous and internal saphenous 

 nen^es ; 19, deep branch of the obturator nen'e to 

 the adductor magnus ; 20, lumbo-sacral trunk; 21, 

 its union with the first sacral nei"ve ; 22, 22, lum- 

 bar and sacral pai-t of the sympathetic nerve ; 23, 

 external cutaneous nerve from the lumbar plexus. 



Another large nerve divides into two sets of 

 branches, which enter the ra,<<tus hitcruus and 

 the crurcus about the middle of those miiscles. 

 The nerve of the vastus intemus, before pene- 

 trating the muscular fasciculi, gives a small 

 branch to the knee-joint. This articular nexxe 

 passes along the internal intermtiscular sep- 

 tum with a branch of the anastomotic artery, 

 as far as the inner side of the joint, where 

 it perforates the capsular ligament, and is 

 directed outwards on the synovial membrane 

 beneath the ligamentum patella;. 



B. Middle cutaneous nerve. — The middle 

 cutaneous nerve either pierces the fascia lata 

 divided into two branches about four inches 

 below Poupart's ligament, or as one trunk 



which soon separates into two branches. These branches descend side by side 

 on the fore part of the thigh to the inner side and front of the patella. After 

 or before the nen-e has become subcutaneous, it communicates with the crural 

 branch of the genito-crural nerve, and also with the internal cutaneous. 



This nerve sometimes arises from the anterior crural, high up within the 

 abdomen. 



C. Internal cutaneous nerve. — The internal cutaneous nerve gives branches 

 to the skin on the inner side of the thigh, and the upper part of the leg; but the 

 extent to which it reaches varies with the presence or absence of the " occasional 

 cutaneous " branch of the obturator nerve. 



Lying beneath the fascia lata, this nerve descends obliquely over the upper 



