The ankle joint anatomy
is not as simple as some might think. It consists of different bones and muscles that surround them. The blood supply and innervation is not too complex. The ankle has a very important function in the body. It supports the body when running and standing. It performs different movements like flexion, extension, plantarflexion and dorsiflexion. The following are the structures that make up the ankle joint:
- Nerves and blood vessels
The bones of the ankle joint are an integral part of the ankle joint anatomy. The bones that make up the ankle joint include: the talus, tibia and fibula. The main bone that forms the ankle is the talus which is why it is called the ankle bone. The talus is connected superiorly to the distal ends of the tibia and fibula. the ankle joint is covered by the articular cartilage which makes it possible for the joint to move freely without friction on the surfaces of the bones that make up the ankle.
There are 6 main muscles that are part of the ankle joint. These muscles include: peroneus longus, peroneus brevis, gastrocnemius, soleus, anterior tibialis and posterior tibialis. The peroneal muscles (longus and brevis) are located on the outer edge of the feet and ankles. Their function is to flex the foot and move it laterally. The gastrocnemius and soleus attach to the calcaneus (which is below the talus) through the Achilles tendon. When there is contraction of these muscles, there is flexion of the ankle. The gastrocnemius muscle and soleus are called the calf muscles. The anterior tibial muscle is the muscle which causes the extension of the foot (movement of the foot upward). The posterior tibial muscle is support of the arch and also it enables the movement of the foot medially.
Ligaments are also very important in the functioning of the ankle joint as well as every other part of the body. Their function in the body is to attach bones to bones. This makes it possible for the bones to be together without falling apart. As small as the ankle joint might seem, there are more than just a few ligaments around the joint. These ligaments include the anterior talofibular ligament, posterior talofibular ligament, calcaneofibular ligament, the deltoid ligament, anterior inferior tibiofibular ligament
, posterior inferior tibiofibular ligament, transvers ligament and the interosseous ligament (only the lower portion is part of the ankle joint).
The tendons are quite similar to ligaments; the difference being that tendons attach muscles to bones. The most important and famous tendon of the ankle is the Achilles tendon. It connects the gastrocnemius and soleus to the calcaneus or heelbone. It is very important for athletes. Most times, athletes have injuries of the Achilles tendon. This prevents them from running and jumping. The other tendons are the anterior and posterior tibial tendons; also there are the peroneal tendons which are located posterior to the lateral malleolus. The functions of the tendons in motility of the foot are basically the same functions as those of the muscles they connect to the bones.
Innervation and blood supply
The ankle is innervated by the tibial nerve. The vessels that supply blood to the ankle joint are the dorsalis pedis (dorsal foot artery) and posterior tibial artery.
Generally the innervation and blood supply in the ankle joint anatomy is from the nerves and vessels going to the foot.