These pages offer advice only. They are no substitute for a proper consultation.
The Ankle Joint
Although often described as a hinge, the ankle is better thought of as a pivot point. The calf muscles pull on the calcaneum through the Achilles Tendon, and the foot is therefore pushed downwards. The Ankle joint relies on maintaining close contact between the talus and tibia/fibula. However, its surface area is far smaller than that of the knee or hip, and any injury to the surfaces can lead the overloading and failure of the cartilage (osteoarthritis).
Sometimes small chunks can be knocked off, leading to osteochondral lesions and loose bodies. Alternatively the lining tissue (synovium) can become inflamed. Any of these conditions can cause pain and gives the ankle a feeling of unsteadiness, weakness, or instability.
The ligaments on the outside of the ankle (lateral ligaments) are especially prone to tearing or spraining. If these do not heal then the joint loses its vital check straps and becomes unstable. This leads to repeated giving way and, with time, further injury to the ankle joint itself.