Arthrodesis is the fusion of a joint. Bone graft is used most often around the joint to hold it together and keep it from moving. As the bone fills in around the bone chips used in the graft, a fusion occurs.
A takedown is used to convert a fused joint into a moveable joint again. A special joint implant is used to restore ankle motion. The most successful of these devices is the Agility total ankle made in the United States.
A takedown operation is fairly new in the United States. There are problems with arthrodesis or takedown. Doctors are working to find ways to improve both operations as they each have their place for different patients.