532 ARTERIES. 



passed beneath it. The artery may now be felt pulsating beneath the deep fascia, about an inch 

 from the margin of the tibia. The fascia having been divided, and the limb placed in such a 

 position as to relax the muscles of the calf as much as possible, the veins should be separated 

 from the artery, and the aneurism needle passed round the vessel from without inwards, so as to 

 avoid wounding the posterior tibial nerve. 



The branches of the posterior tibial artery are, the 



Peroneal. Nutrient. 



Anterior peroueal. Communicating. 



Muscular. Internal calcanean. 



The Peroneal Artery lies, deeply seated, along the back part of the fibular 

 side of the leg. It arises from the posterior tibial, about an inch below the 

 lower border of the Popliteus muscle, passes obliquely outwards to the fibula, 

 and then descends along the inner border of that bone to the lower third of the 

 leg, where it gives off the anterior peroneal. It then passes across the articula- 

 tion between the tibia and fibula, to the outer side of the os calcis, supplying 

 the neighboring muscles and back of the ankle, and anastomosing with the 

 external malleolar, tarsal, and external plantar arteries. 



Relations. This vessel rests at first upon the Tibialis Posticus, and, in the 

 greater part of its course, in the fibres of the Flexor Longus Pollicis, in a groove 

 between the interosseous ligament and the bone. It is. covered in the upper part 

 of its course by the Soleus and deep fascia; below, by the Flexor Longus Pollicis. 



PLAN OF THE RELATIONS OF THE PETJONEAL ARTERY. 



In front. 



Tibialis Posticus. 

 Flexor Lomms Pollicis. 



Outer side. 

 Fibula. 



Behind. 



Soleus. 



Deep fascia. 



Flexor Longus Pollicis. 



Peculiarities in Origin. The peroneal artery may arise three inches below the Poplitens, or 

 from the posterior tibial high up, or even from the popliteal. 



It.* Size is more frequently increased than diminished ; and then it either reinforces the poste- 

 rior tibial by its junction with it, or altogether takes the place of the posterior tibial in the lower 

 part of the leg and foot, the latter vessel only existing as a short muscular branch. In those 

 rare cases where the peroneal artery is smaller than usual, a branch from the posterior tibial 

 supplies its place, and a branch from the anterior tibial compensates for the diminished anterior 

 peroneal artery. In one case, the peroneal artery has been found entirely wanting. 



The anterior peroneal is sometimes enlarged, and takes the place of the dorsal artery of the 

 foot. 



The peroneal artery, in its course, gives off branches to the Soleus, Tibialis 

 Posticus, Flexor Longus Pollicis, arid Peronei muscles, and a nutrient branch 

 to the fibula. 



The Anterior Peroneal, the only named branch of the peroneal artery, pierces 

 the interosseous membrane, about two inches above the outer malleolus, to 

 reach the fore part of the leg, and, passing down beneath the Peroneus Tertius 

 to the outer ankle, ramifies on the front and outer side of the tarsus, anastomos- 

 ing with the external malleolar and tarsal arteries. 



The nutrient artery of the tibia arises from the posterior tibial near its origin, 

 and after supplying a few muscular branches, enters the nutrient canal of that 

 bone, which it traverses obliquely from above downwards. This is the largest 

 nutrient artery of bone in the body. 



