You are asking about the natural history of a condition called osteochondral lesion of the talus (OTL). Other terms used to describe OLT include osteochondritis dissecans, transchondral fracture, talar dome fracture, and flake fracture.
In this condition, damage to the talus after an ankle sprain or other ankle injury causes a loose fragment. This piece of cartilage gets stuck between the top of the talus and the bottom of the tibia (shinbone) located just above the talus. The talus is a bone in the ankle wedged between the calcaneus (heel bone) below and the tibia above.
Although the problem is fairly uncommon, there have been studies to report long-term outcomes. The main finding has been that the frayed or torn cartilage does not heal well. Symptoms of pain, swelling, and locking up of the joint simply do not go away. Less than half the patients treated nonoperatively have success with nonoperative treatment.
On the other hand, surgery isn’t always successful. Three-fourths of the patients in one study had a good-to-excellent outcome. Twenty-five per cent (one in four) developed degenerative arthritis. Researchers are still trying to identify factors that might predict ahead of time who will have a good result with surgery.
So far, it does not look like the results of treatment are linked with age, gender, or the side affected (right or left ankle). Delays between injury and surgery did not seem to make any difference in the final results. Worker’s compensation patients did have poorer results compared with those who were not on worker’s comp.
The best advice of experts on this condition is to give the nonoperative plan of care a good try before having surgery. If your symptoms are not improved after four to six months of conservative care, then consult with your surgeon about what surgery can do for you, the risks, possible complications, and expected outcomes.