The peculiarities of this artery relate to its origin, its course, its size, and the condition of its branches.
In cases of premature division of the popliteal artery, the place of origin of the anterior tibial is necessarily higher up than usual, being sometimes found as high as the bend of the knee-joint. In some of these cases (the posterior tibial artery being small or wanting), the anterior tibial is conjoined with the peroneal artery. When the anterior tibial arose higher than usual, the additional upper part of the vessel has been seen resting on the popliteus muscle, and it has likewise been found between that muscle and the bone.
The anterior tibial, having its usual place of origin, has been found to deviate outwards towards the margin of the fibula in its course along the front of the leg, and then to return to its ordinary position beneath the annular ligament in front of the ankle-joint. This artery has also been noticed by Pelletan* and by Velpeau** to approach the surface at the middle of the leg, and to continue downwards from that point, covered only by the fascia and integument.
The last-named observer states that he found the artery reach the fore part of the leg by passing round the outer side of the fibula.}
This vessel more frequently undergoes a diminution than an increase of size.
It may be defective in various degrees. Thus, the dorsal branch of the foot may fail to give off digital branches to the great and second toes, which may then be derived from the internal plantar (a branch of the posterior tibial). In a further degree of diminution the anterior tibial ends in front of the ankle, or at the lower part of the leg : its place being then taken by the anterior division of the peroneal artery, which supplies the dorsal artery of the foot ; the two vessels (anterior tibial and anterior peroneal) being either connected together, or separate.
Two cases are mentioned by Allan Burns, in which the anterior tibial artery was altogether wanting, its place in the leg being supplied by perforating branches from the posterior tibial artery, and on the dorsum of the foot by the anterior division of the peroneal artery.
The dorsal artery of the foot is occasionally larger than usual ; in that case compensating for a defective plantar branch from the posterior tibial artery.
This artery has been repeatedly found to be curved outwards, between its commencement at the lower border-of the annular ligament and its termination at the first interosseous space.
From Quain's anatomy.