(3.02)
Now we’ll look at the blood vessels and nerves of the foot, starting with the veins. The superficial veins of the lateral aspect of the foot join together to form the short saphenous vein. The ones on the medial aspect of the foot join together to form the long saphenous vein.
In addition, at a deeper level, the arteries, which we’ll be looking at next, are closely accompanied by concomitant veins, like these. From here on we’ll remove all the concommitant veins to simplify the picture.
We last saw the anterior, and posterior tibial arteries entering the foot, beneath the extensor retinaculum and flexor retinaculum respectively. Here’s the anterior tibial artery at the ankle, passing beneath the extensor retinaculum. We’ll remove the retinaculum.
As it passes in front of the ankle, the anterior tibial artery crosses beneath extensor hallucis longus, emerging lateral to it. It gives off branches to the tarsal region, then continues on to the dorsum of the foot. Beyond this point it’s known as the dorsalis pedis artery.
The dorsalis pedis artery passes beneath the extensor hallucis brevis muscle, gives off this first dorsal metatarsal artery, and ends by diving through the first interosseous muscle to join up with the lateral plantar artery which we’ll see in a minute.
Now we’ll look at the posterior tibial artery, or rather, at its two terminal branches, the medial plantar, and lateral plantar arteries. Here’s where we saw them last, emerging from under the flexor retinaculum, the lower part of which has been removed in this dissection. Also removed, are the abductor hallucis muscle, here, and the plantar aponeurosis, here. This is the distal end of the posterior tibial artery. This is the the lateral plantar artery, this is the medial plantar artery.
The medial plantar artery is usually the smaller of the two. It crosses over the tendons of the two long toe flexors, and runs along the medial side of the foot. Its branches supply the adjoining muscles, and the underside of the big toe.
Now we’ll look at the lateral plantar artery. It passes deep to flexor digitorum brevis, which we’ll remove. After giving off this calcaneal branch, the lateral plantar artery passes downwards and then laterally, across flexor accessorius. When it reaches the base of the fifth metatarsal, which is here, it curves around and passes deep to flexor digitorum longus and the interosseous muscles, to join up with the dorsalis pedis artery.