Your ankle, together with your foot is one of the most complex and hard-working parts of your body. It consists of 28 bones and 33 small joints, all held together by a network of soft tissue made up of muscles, tendons, ligaments, nerves, and blood vessels. So, how do you know which part is your ankle and which part is your foot? Don’t they do pretty much the same thing?
The ankle joint is also called the tibiotalar joint and it is the junction between your lower leg and your foot. Basically, the area around that knob of bone that sticks out at the side of your ankle.
Three different bones make up your ankle joint. The tibia (shin bone) and fibula in your lower leg forms a hinge joint with the talus (ankle bone) just above your calcaneus (heel bone). The joint space is called the ankle mortise and the whole joint is covered by a layer of tissue, called the joint capsule.
Ligaments are tough layers of connective tissue that connects bones to each other. They provide stability to the ankle and foot. The ankle ligaments are called:
- Medial (deltoid) ligaments (found at the inside of your ankle): Tibiocalcaneal ligament, tibionavicular ligament, anterior and posterior tibiotalar ligaments.
- Lateral ligaments (found at the outside of your ankle): Calcaneofibular ligament, anterior and posterior talofibular ligaments. The anterior talofibular ligament is the weakest of the three lateral ligaments and thus the most frequently injured in ankle injuries.
Muscles and tendons:
The muscles around your ankle can be divided into three groups:
- Posterior muscles (At the back of the ankle): The gastrocnemius and soleus muscles are the strongest, primary muscles in this group. Smaller muscles in this group includes: Tibialis posterior, flexor hallucis longus, flexor digitorum longus and plantaris. Together, they give you the ability to point your toes (plantarflexion and toe flexion), or push off the ground to launch you into the air.
- Anterior muscle group (front of the ankle): This group consists of the tibialis anterior, extensor digitorum longus and extensor hallucis longus. The tibialis anterior muscle, is the primary muscle that gives you the ability to lift your foot and toes upward and inward (dorsiflexion and inversion). These muscles control your decent down when running down a hill.
- Lateral muscle group (outside of the ankle): The peroneus longus and peroneus brevis muscles function together to give you an outward movement of your ankle (eversion). These work overtime when balancing the foot a you tightrope walk over a pole.
It is important to understand that all these muscles actually come from higher up in your leg. They stretch from close to your knee all the way down to your ankle and foot. Some of them attach onto your toes. So, they produce both ankle and toe movement.
Each of these muscles end in a tendon, which is the part that anchors the muscle onto the bone. A tendon is made of stronger collagen fibres, so they are not as flexible as muscles. These tendons cross your ankle joint to help keep the alignment and stability during forceful landings.
Nerves and bloodvessels
There is a whole network of arteries, veins and and nerves in your ankle and foot. We tend to forget about them, but they can just as easily be part of what is causing your ankle joint pain.
Nerves stimulate the right muscles at the right time, allowing you to move your foot and gives you the ability to feel different sensations on your skin. Important nerves in and around your ankle are: the tibial nerve and the common peroneal nerve.
Blood and oxygen travels through your arteries and veins to ensure that your feet have good circulation.