Ankle replacement, also known as total ankle replacement or ankle arthroplasty, is an operation for treatment of arthritis of the ankle.
In the early stages, ankle arthritis can often be controlled with simple treatments such as painkillers, ankle braces and physiotherapy. When the condition progresses to the point where these treatments are no longer helpful then surgery is considered. In advanced arthritis of the ankle, there is often the option of either having fusion or replacement of the ankle joint.
In ankle replacement, the worn surfaces of the joint are removed. A metal component is used to resurface each of the bones. A plastic spacer is inserted between the metal surfaces to preserve and restore the movement of the joint. The aim of the surgery is to relieve pain from the worn joint while preserving movement.
For more advanced arthritis of the ankle, the options are either ankle fusion or ankle replacement. There is often no right answer as to which option to choose and there are advantages and disadvantages to both. For some people there can be reasons why an ankle replacement cannot be performed but for most people both options are available. Ankle replacement is not recommended in people with certain advanced deformities, soft bone, previous infections, or poor blood supply to the foot.
Ankle fusion can often be carried out by keyhole surgery (arthroscopic ankle fusion). The advantage of an ankle fusion is that once the bones heal together the pain relief is excellent and long lasting. The disadvantage is that the recovery can be more lengthy and there is an increased load on the adjacent joints which can in turn wear out later on although this process usually takes several decades. People having an ankle fusion are often pleasantly surprised by how much movement they retain in the rest of the foot and the impact on gait is usually far less than might be expected. There are even professional footballers who have continued to play after an ankle fusion!
Ankle replacement has the advantage of preserving movement in the joint, relieving the strain on other joints and creating a more natural gait. The recovery is also quicker with usually only two weeks being required in cast. There are some drawbacks. Like any artificial joint it can wear out – ankle replacements are good but 20% can be expected to fail before ten years. Some people (around 10%) will have some ongoing unexplained pain which is not always easy to treat. Some people will require additional minor surgery in future years, for example to tidy up the joint or to fill cysts that can form.
The decision about whether to have a fusion or replacement will depend on many factors including your own preferences as well as your age, activity level, overall health, and also the specific condition of your ankle joint. Our specialist surgeons can take all these factors into account and discuss which might be the better treatment option for you.
The operation is performed under a general or spinal anaesthetic. An incision is made at the front of the ankle. The old worn joint surfaces are removed and the new metal and plastic components are inserted. X-rays are taken during the procedure to confirm the best positioning of the implants. The wound is closed with stitches or staples and the leg is placed in cast.
For some people with other problems in the foot, additional procedures are performed at the same time, for example to fuse other worn joints, realign bones to correct deformity or to repair ligaments or tendons.
Usually you would be in a cast for the first two weeks and you would normally be allowed to bear weight straight away in the cast. You will be likely to require sticks or crutches to steady yourself in the early stages of recovery. There will be some swelling and you will need to keep your foot elevated on a footstool in the early recovery period.
After two weeks you would have an appointment in clinic to remove the cast, check the wound and remove the skin clips. You would then start physiotherapy for help regaining the movement in the ankle and general recovery and rehabilitation.
By six to eight weeks you will usually have returned to most day to day activities but for anything requiring prolonged periods of time on your feet it will take longer. You can usually drive after about six weeks – you need to be sufficiently comfortable and strong to control the foot pedals. It can take 3-6 months for all the swelling to settle down.
The aim would be to provide you with an ankle replacement that lasts a lifetime. However this is not always the case and in some people the ankle replacement will fail at some point and require revision. Overall about 80% of patients will find their ankle replacement is still serving them well at ten years after surgery.
For some people minor “tidying up” operations can be required in future years, such as to fill any cysts (holes) that may form in the bone or to clean excess bone out from the sides of the joint.
If an ankle replacement fails completely it may be necessary to fuse the ankle joint or redo the replacement.
All surgery carries risks, and ankle replacement surgery is no exception. The risks will be discussed with your treating surgeon and in particular whether you are at higher than normal risk. These include: