Ankle replacement is an operation to replace a worn out ankle joint.

When is an Ankle Replacement recommended?

• Ankle replacements are done to treat arthritis which causes pain in the ankle that cannot be controlled by simple measures such as painkillers, shoe inserts, physiotherapy or a walking stick.
• When a person has osteoarthritis of the ankle which is a wearing out of the joint lining often as a result of a previous injury (it can also happen spontaneously for no apparent reason).
• When a person has rheumatoid arthritis which is a generalised inflammation of many joints in the body which can cause ankle pain. 

When is an Ankle Replacement not recommended?

There are certain circumstances when it would not be advised because of a high failure rate. It would not be suitable if:

• You are young (usually under 55) or very physically active.
• You have a severe foot deformity.
• Your ankle is very unstable.
• You have had infection in the ankle or the bones around it.
• The bone under the ankle (the talus) has collapsed.

In these situations, a fusion would be advised instead.

How is an Ankle Replacement performed?

Ankle replacement is performed through an incision approximately 15 cm (6 inches) long over the front of the ankle. The worn out joint surfaces are cut away and replaced with 2 pieces of metal with a piece of hard plastic between them that allows the joint to move freely. The operation takes between 60 and 90 minutes. Sometimes other operations are required at the same time, such as Achilles tendon (heel cord) lengthening to allow full movement of the ankle joint and this will mean three extra very small cuts at the back of the ankle.

How long do you spend in hospital?

Most people who are reasonably fit can come into hospital on the day of surgery, having had a medical check up 2-6 weeks before. After surgery, your foot may swell and, if this happens, you will have to rest with your foot raised to help the swelling to go down. This may take anything from 2 days to a week. Once the swelling goes down and the wounds are clean you will be put in plaster or a brace. You can get up with the aid of crutches and go home. The physiotherapist will teach you how to walk with crutches. We will get you up as soon as possible! Most people are in hospital for 2-3 days.

Will I have to go to sleep (general anaesthetic)?

The operation is usually done under general anaesthetic (asleep). Alternatively, an injection can be put into your back to make your legs numb while you remain awake (spinal anaesthetic). These do not always work and, in that case, you may have to go to sleep if the operation is to be done. Your anaesthetist will advise you about the best choice of anaesthetic for you. In addition, local anaesthetic may be injected into your leg while you are asleep to reduce the pain after the operation even if you go to sleep for the surgery. You will also be given painkilling tablets as required. Once the swelling goes down and the cuts on your foot are healing, it will be put in plaster and you can get up with crutches and go home. The physiotherapist will show you how to walk with crutches. We will get you up as soon as possible! Most people are in hospital for 2-3 days.

Will I have a plaster on afterwards?

You will need to wear a plaster or brace from your knee to your toes until the cuts in the bones around the ankle have healed. This will be approximately 6 weeks.

What will happen after I go home?

By the time you go home you will have mastered walking on crutches, keeping the weight off your foot. You should go around like this for 2 weeks. For the first 2-4 weeks it is very important to keep your leg elevated as much as possible to help reduce swelling and allow the wounds to heal. Walk only for essential purposes. Do not stand immobile for more than a few minutes and elevate the leg whenever sitting. Approximately 2 weeks after your operation you will be seen in the clinic by a nurse. Your plaster will be removed and the cuts and swelling on your foot checked. If all is well, you will be put back in plaster or a brace. You should continue walking with your crutches, but, at this stage, you can begin putting more weight through your foot. About 6 weeks after your operation you will come back to the clinic and the plaster or brace will be removed and an x-ray performed. If all is satisfactory you will now be able to walk on your ankle without plaster or crutches. You will be referred for physiotherapy to help mobilise the ankle.

How soon can I....

Walk on the foot

You should walk keeping the weight off your foot for 2 weeks after surgery. Your surgeon or nurse will advise you when you can start taking some weight on the foot. When you start putting weight on your foot we will give you a special shoe that you can wear over your plaster.

Go back to work

If your foot is comfortable and you can keep your foot up and work with your foot in a special shoe, you can go back to work within 3-4 weeks of surgery. In a manual job with a lot of dirt or dust around and a lot of pressure on your foot, you may need to take anything up to 6 months off work. How long you are away from work will depend on where your job fits between these 2 extremes.

Drive

Most people prefer not to drive until the plaster is off, they can wear a shoe and are able to fully weight bear. Drive short distances before long ones. If you cannot safely make an emergency stop your insurance will not cover you in the event of an accident. If only your left foot is operated on and you have an automatic car, you can drive within a few weeks of the operation, when your foot is comfortable enough and you can bear weight through it.

Play sport

After your plaster is removed you can start increasing exercise. Gentle walking, cycling or swimming are all good exercises both for your heart and the ankle replacement. Vigorous or impact type exercise such as running, football or squash should not be done at any stage after an ankle replacement. If you wish to do this type of exercise then you should not have an ankle replacement.

Risks

COVID-19 infection increases the risk of complications and we recommend you read the separate leaflet about this. If you are in one of the vulnerable groups you should think very carefully about proceeding with surgery unless it is absolutely necessary.

Chronic regional pain syndrome (CRPS)

Complex regional pain syndrome (CRPS) is a broad term describing excess and prolonged pain and inflammation that follows an injury to an arm or leg. CRPS has acute (recent, short-term) and chronic (lasting greater than six months) forms.

Infection

The most serious thing that can go wrong is infection in the ankle. This only happens in less than 1 in 100 people, but, if it does, it is serious. Further surgery to drain and remove the infected replacement will be necessary. You may then need more surgery to fuse the ankle (stiffen it completely). After an infection it is very unlikely another replacement would be offered

Reliability

Ankle replacements are not yet as reliable as hip or knee replacements. We know that approximately 85-90 out of 100 ankle replacements will still be in place 10 years after surgery. If the ankle does wear out, become loose or “fail”, then it will be removed and probably changed to a fusion. Second time ankle replacements are very rare unless there is a specific problem that can be fixed. This is because there is a limited amount of bone in the ankle joint unlike hip and knee. Often there is little bone left to fit the ankle replacement.

Some ankle replacements will loosen early (within 12 years) and require surgery sooner rather than later.

Nerve damage

The incision used for ankle replacement is close to several nerves in the foot, which can be stretched or occasionally permanently damaged leading to some numbness on the foot. Occasionally, there is pain associated with this damage that does not settle with time.

Pain

It is common to experience some on-going less severe pain after ankle replacement. This is because arthritis often affects several joints in the foot and the ankle replacement is only designed to replace one of them. Usually the pain is much improved but further surgery may be required to treat the other joints.

Movement

After ankle replacement it is unusual to regain any more movement than was present beforehand as this is determined by ligaments and tendons which are not replaced. In severe cases of arthritis with little ankle movement your surgeon may recommend a fusion instead.

Deep Vein Thrombosis

Ankle replacement is a major operation and there is a risk of DVT (deep vein thrombosis) and/or PE (pulmonary embolism) due to blood clots. We do everything to minimise these risks but they occur in a very small percentage of patients and can be serious.