378 Anatomy Applied to Medicine and Surgery. 



on the ti'bialis posticus muscle at the same level and about 

 midway between the bones. The posterior tibial nerve 

 lies close to the inner side of the artery. Holden draws 

 attention to the fact, that, in amputations one inch below 

 the head of the fibula, only one main artery is divided. In 

 amputations two inches below it, two main arteries are 

 divided the anterior and the posterior tibial, while in am- 

 putations three inches below the head, three main arteries 

 the two tibials and the peroneal are divided. Amputa- 

 tion through the middle of the leg may be performed by 

 means of a large posterior flap. The length and breadth of 

 the posterior flap are equal to one-third the circumference, 

 at the level of the saw line, i.e., to the diameter of the leg 

 at this level, whereas, the anterior flap is one-third the 

 length of the posterior. The incisions are commenced 

 about one inch below the point where the bones are to be 

 sawn so as to allow for retraction. The inner limb of the 

 U-shaped posterior flap is just behind the inner border of 

 the tibia, while the outer limb of this flap is posterior to 

 the peronei muscles. 



In the stump, after this amputation, the anterior tibial 

 artery lies on the interosseous membrane between the tib- 

 ialis anticus and the extensor proprius hallucis with the 

 nerve in front of it, the posterior tibial is found 

 lying between the superficial and the deep planes of mus- 

 cles with the nerve to its outer side, while the peroneal 

 vessels will be close to the fibula lying on the flexor lon- 

 gus hallucis. Amputation through the lower third 

 of the leg may be performed by means of the large pos- 

 terior flap. This large posterior flap, after retraction, 

 which causes it to lose about one-third of its length, 

 should be equal to, in length, the half of the circumference 



