CUTANEOUS NERVES OX THE FRONT OF THE LEG. 177 



and third toes : it communicates with the internal saphenous and 

 the anterior tibial nerves. 



The outer branch ( 4 ) also divides into two nerves ; these lie over outer 

 the third and fourth interosseous spaces, and bifurcate at the web r 

 of the foot for the contiguous sides of the three toes corresponding 

 with those spaces : it communicates with the external saphenous 

 nerve on the outer border of the foot. 



The ANTERIOR TIBIAL NERVE (l) becomes CUtaneOUS in the first Anterior 



interosseous space, and is distributed to the opposed sides of the fjjjjj. where 

 great toe and the next. The musculo-cutaneous nerve communi- 

 cates with it, and sometimes assists in supplying the same toes. 



The EXTERNAL SAPHENOUS NERVE (fig. 71, 5 , p. 188) comes from External 



the back of the leg below the outer ankle, and is continued along sap e 

 the foot to the outside of the little toe ; all the outer margin of the 

 foot receives nerves from it, and the offsets towards the sole are 

 larger than those to the dorsum. Occasionally it supplies both 

 sides of the little toe and part of the next, joining with the outer 

 branch of the musculo-cutaneous. 



INTERNAL SAPHENOUS NERVE (fig. 66, 5 ). This nerve is con- internal 

 tinned along the vein of the same name to the middle of the instep, sap^uous. 

 where it ceases mostly in the integuments, but some branches pass 

 through the deep fascia to end in the tarsus. 



The DEEP FASCIA of the front of the leg is thickest near the Deep fascia 

 knee-joint, where it gives origin to muscles. On the inner side it is of the leg ; 

 tixed to the anterior border of the tibia ; but externally it is continued intermus- 

 round to the back of the leg. A strong intermuscular septum is cular se P ta ; 

 sent in from the deep surface to the anterior border of the fibula, 

 separating the anterior and external muscles : and another weaker 

 process passes backwards in the upper third of the leg between the 

 tibialis anticus and extensor longus digitorum. Above, the fascia 

 is connected to the heads of the leg-bones ; and below, it is 

 continued to the dorsum of the foot. 



Above and below the ankle-joint it is strengthened by some transverse 

 transverse fibres, and gives rise to the two parts of the anterior JJJj^ at the 

 annular ligament ; and below the end of the fibula it forms 

 another band, the external annular ligament. 



Dissection. The fascia is to be removed from the front of the Take away 

 leg and the dorsum of the foot, but the thickened bands of the the fascia> 

 annular ligament (fig. 67) above and below the end of the tibia 

 are to be left. In separating the fascia from the subjacent muscles, 

 let the edge of the scalpel be directed upwards. 



In like manner the fascia may be taken from the perouei muscles leave liga- 

 on the outer side of the fibula, but without destroying the band h^d us 

 (external annular ligament) below that bone. 



On the dorsum of the foot, the dorsal vessels (fig. 70, p. 183) clean 

 with their nerve are to be displayed, and the tendons of the short vessels. 

 and long extensors of the toes are to be traced to the ends of the 

 digits. In the leg, the muscles are to be cleaned and separated 

 from one another, and the anterior tibial nerve and vessels are to 

 be followed from the dorsum into their intermuscular space, and 



D.A. X 



