Ankle arthritis is one type of arthritis that can be extremely painful for individuals. To fully understand this disease, it is helpful to understand the anatomy of the ankle and why osteoarthritis is more likely in this area.
The following details will help you understand the anatomy of your ankle:
- The fibula bones from the shin and the long tibia meet with the talus bone on the foot at the ankle.
- The talus bone is odd shaped, and it sits on the calcaneus (or the heel bone)
- Flexible, strong, slippery articular cartilage rests on the places where the bones meet. This provides cushioning, and it facilitates joint movement.
People that have osteoarthritis commonly develop arthritis in their ankles. Most of the time, their joints start to degenerate between the tibia, talus, and fibula. In some cases, degeneration may occur been the talus and calcaneus, but this is less likely.
The cartilage in the ankle varies from other weight bearing joints. It is much thinner than other joint areas. Healthy ankles have cartilage between 1 to 1.7 mm thick. A knee, on the other hand, will have cartilage ranging from 1 to 6 mm thick. Ankle cartilage is also very dense. It’s tougher than most cartilage and tends to perform well with weight-bearing activities. For this reason osteoarthritis in the ankles is less likely if there are no previous injuries.
How Pain Is Caused
Although osteoarthritis is less likely, it still occurs. If the cartilage in the ankle is extremely thin, damaged, or gone, then a few scenarios may occur:
- Sometimes new cartilage is created, but it is irregular. Good cartilage is smooth, and this new cartilage is usually bumpy, causing the tibia and talus to grind and rub against each other.
- The bones might produce osteophytes, or bone spurs. These also cause friction in the ankle joint.
- A person’s body might compensate for the loss of cartilage. This might result in the stretching of ligaments and tendons, causing additional ankle problems.
In osteoarthritis cases, damaged cartilage is not the primary source of pain. Instead, it is the friction that often creates the most discomfort.