Talar Dome Osteochondral Lesion

The ankle bone is called the talus, which is topped by the talar dome linking to the tibia (shin bone). This dome is coated with a layer of strong cartilage to facilitate effective ankle movement. When the cartilage and the talus below become injured, this causes an osteochondral lesion – meaning a lesion affecting both bone and cartilage. This is often provoked by an existing injury.

Symptoms

The injury is regularly asymptomatic for a long period unless the lesion is severe. After a number of months (or sometimes longer), possible symptoms include persistent pain in the ankle which is worsened during activity and weight bearing, inflammation of the area which may also occur concurrently with activity, pronounced weakness in the ankle, and a click or feeling of rigidity while walking. The ankle can also seem to lock into position and suffer from restricted movement.

Causes

The osteochondral lesion is typically caused due to ankle trauma, whether directly – following quickly after an incident – or with another injury arising initially and subsequently causing the lesion. Such injuries include ankle sprains and tendonitis; if the cartilage does not fully recover from these (or other) ankle conditions then part of the cartilage can become unstuck and sit unnaturally within the ankle. For a detailed look at the causes of ankle sprains please see our relevant articles.

Medical Treatment

You will need to see a doctor to have the injury diagnosed. Treatment will vary depending on the injury's severity. The incidence of floating fragments of cartilage (or bone) can indicate a major lesion and might require surgery, but for more minor injuries there are several non-operative measures. The doctor may fit you with a cast in order to immobilise the ankle; during this period it is essential to rest from any strenuous activity so as not to exacerbate the condition. After this, physical therapy will help to maintain movement in the joint and gradually build up strength. Anti-inflammatory pain medication, such as ibuprofen, can be useful for reducing pain and swelling.

If the injury is deemed 'unstable' and involves broken fragments of cartilage or bone, the course of action will depend on the doctor's assessment of the lesion. An ankle brace can often help to minimise the risk of repeating the injury. The doctor may recommend one of many surgical procedures to remove loose fragments from the ankle; this will result in clearing the way for recovery.

Post-Injury

Due to the manner in which the lesion can damage the ankle cartilage, problems can often continue after the injury has healed. In some cases the pain and swelling can remain, or limited foot motion can persist. Arthritis may develop in severe instances. If any of these conditions arise then a doctor will talk you through the treatment options, which might involve a productive program of physical therapy, a course of medication, or surgery.