ANTERIOR TIBIAL. 44T 



Relations. In the upper tworthirds of its extent, it rests upon the interosseous 

 ligament, to which it is connected by delicate fibrous arches thrown across it. 

 In the lower third, upon the front of the tibia, and the anterior ligament of the 

 ankle-joint. In the upper third of its course, it lies between the Tibialis anticus 

 and Extensor longus digitorum; in the middle third, between the Tibialis anticus 

 and Extensor proprius pollicis. In the lower third, it is crossed by the tendon of 

 the Extensor proprius pollicis, and lies between it and the innermost tendon of the 

 Extensor longus digitorum. It is covered, in the upper two-thirds of its course, 

 by the muscles which lie on either side of it, and by the deep fascia ; in the lower 

 third, by the integument, annular ligament, and fascia. 



The anterior "tibia! artery is accompanied by two veins (vensa comites), which 

 lie one on either side of the artery ; the anterior tibial nerve lies at first to its outer 

 side, and about the middle of the leg is placed superficial to it ; at the lower part 

 of the artery, the nerve is on the outer side. 



PLAN OF THE KELATIONS OF THE ANTERIOR TIBIAL ARTERY. 



In front. 



Integument, superficial and deep fasciae. 

 Tibialis anticus. 

 Extensor longus digitorum. 

 Extensor proprius pollicis. 

 Anterior tibial nerve. 



Inner side. f N, Outer side. 



Tibialis anticus. / . \ Anterior tibial nerve. 



Extensor proprius pollicis. ( Viblai ' Extensor longus digitorum. 



Extensor proprius pollicis. 



Behind. 



Interosseous membrane. 

 Tibia. 

 Anterior ligament of ankle-joint. 



Peculiarities in Size. This vessel may be diminished in size, or it may be deficient to a greater 

 or less extent, or it may be entirely wanting, its place being supplied by perforating branches 

 from the posterior tibial, or by the anterior division of the peroneal artery. 



Course. This artery occasionally deviates in its course towards the fibular side of the leg, 

 regaining its usual position beneath the annular ligament at the front of the ankle. In two 

 instances, this vessel has approached the surface in the middle of the leg, from this point onwards 

 being covered merely by the integument and fascia. 



Surgical Anatomy. The anterior tibial artery may be tied in the upper or lower part of the 

 leg. In the upper part, the operation is attended with great difficulty, on account of the depth 

 of the vessel from the surface. An incision, about four inches in length, should be made through 

 the integument, midway between the spine of the tibia and the outer margin of the fibula, the 

 fascia and intermuscular septum between the Tibialis anticus and Extensor communis digitorum 

 being divided to the same extent. The foot must be flexed to relax these muscles, which 

 must be separated from each other by the finger. The artery is then exposed, deeply seated, 

 lying upon the interosseous membrane, the nerve lying externally, and one of the venae comites 

 on either side ; these must be separated from the artery before the aneurism needle is passed 

 round it. - 



To tie this vessel in the lower third of the leg above the ankle-joint, an incision about three 

 inches in length should be made through the integument between the tendons of the Tibialis 

 anticus and Extensor proprius pollicis muscles, the deep fascia being divided to the same extent; 

 the tendon on either side should be held aside, when the vessel will be seen lying upon the tibia, 

 with the nerve superficial to it, and one of the venae comites on either side. 



In order to secure this vessel over the instep, an incision should be made on the fibular side 

 of the tendon of the Extensor proprius pollicis, between it and the innermost tendon of the long 

 Extensor ; the deep fascia having been divided, the artery will be exposed, the nerve lying either 

 superficial to it, or to its outer side. 



