Ankle Arthrodesis (Ankle Fusion)

What is an ankle arthrodesis?

The goal of ankle arthrodesis (also commonly known as ankle fusion) is to relieve pain and maintain or improve function for a patient with ankle arthritis. Ankle arthritis is degeneration of the cartilage that covers the ends of the bones that form the ankle joint. These bones are the tibia, the fibula, and the talus. Pain typically is made worse with movement of the arthritic ankle. The goal of ankle arthrodesis is to take the ankle bones and fuse them into one bone. This eliminates motion and reduces pain from the arthritic joint.

How long will I have to stay in hospital?

You will come into hospital on the day of your operation and usually stay in for one night

What happens before the operation?

Prior to admission you will need to have a pre‐  operative assessment. This is an assessment of your health to make sure you are fully prepared for your admission, treatment and discharge. The pre‐operative assessment nurses are there to help you with any worries or concerns that you have, and can give you advice on any preparation needed for your surgery.

Before the date of your admission, please read very closely the instructions given to you.   If you are undergoing a general anaesthetic you will be given specific instructions about when to stop eating and drinking, please follow these carefully as otherwise this may pose an anaesthetic risk and we may have to cancel your surgery.  

What happens after surgery?

During the immediate post‐operative period it is important to keep the fused ankle elevated to minimize swelling. Ideally this means keeping the ankle above your bottom by lying down or sitting in a reclined position.

The tibia and talus require at least six to eight weeks before they are fused sufficiently to begin weightbearing. It may take as long as 10 to 12 weeks. During this time patients typically do not put weight on their operative leg. Most patients find navigating their daily lives without putting weight on one leg difficult.

Patients typically use crutches or wheelchairs to get about. It is helpful to have someone on hand to help with basic tasks and activities at home, especially during the first two weeks. Non‐absorbable stitches are typically removed 10 to 14 days after surgery. During the first few weeks after surgery, swelling and pain will increase when the foot is not elevated. Mild amounts of swelling and pain when the foot is below the heart for long periods of time may persist for months, but will gradually improve over time.

After sufficient time has passed, patients slowly begin placing weight on their ankle using a walking boot at about 6 weeks. X‐rays will be obtained to confirm that the ankle is fusing well at 6 and 12 weeks after your operation. After 12 weeks, the ankle fusion is typically stong enough to allow walking out of the plastic boot and a gradual return to more vigorous activity.

What are the complications of an ankle arthrodesis?

A specific risk associated with ankle arthrodesis is nonunion. This is failure of the ankle bones to fuse together. The ankle bones successfully fuse in more than 90 percent of operations, so the risk is relatively low. If nonunion does occur, a second operation may be needed.

Loss of motion in the ankle after a fusion causes the other joints in the foot to bear more stress than they did prior to the surgery. This can lead to an increased rate of arthritis in those other joints. This typically takes several years to develop and may or may not be symptomatic.

There is a small risk of a clot forming in the leg veins (Deep Venous Thrombosis or DVT) after surgery and plaster cast. This is the same type of clot that passengers on long aeroplane flights may develop. A DVT may cause the leg to swell and occasionally the clot may break loose and lodge in the lung (Pulmonary embolism or PE). Overall the risk of a DVT or PE is small and we will take active measures to minimise this risk to you.

A DVT is more likely if you are overweight or smoke. You can reduce the risk of developing a DVT by getting up and walking about as soon as possible after your operation.

A DVT may only be obvious after you have gone home. If you notice any swelling of the calf or more rarely the thigh, or you experience pain or tenderness in the calf, or notice that your leg is shiny or discoloured you should seek medical advice quickly. You should also contact a doctor immediately if you develop shortness of breath or pain on breathing following surgery.