Fusion of a joint (also known as arthrodesis) is intended to relieve pain and maintain or improve function for patients with ankle arthritis (for more information about ankle arthritis click here [link to arthritis page]. In fusion surgery the bones either side of the joint are fused into one bone. This eliminates the joint motion and reduces pain coming from the arthritic worn out joint. Surgery is recommended when the arthritis is severe and the simple non-operative treatments no longer work.
For many people fusion surgery of the ankle can now be carried out by keyhole (arthroscopic) surgery. For most other fusion surgery in the foot the operation is carried out by open surgery. Find out more about arthroscopic ankle fusion surgery. Your surgeon will be able to advise whether the arthroscopic technique is suitable for you.
For most people only one joint will need to be fused. However in some people more than one joint can be affected. Sometimes it will be necessary to fuse more than one joint at the same time. In practical terms what you would go through at surgery would be similar whether it is one or more than one joint involved.
You would have a general or spinal anaesthetic. Cuts are made to allow access to the joint and tools are used to remove any remaining cartilage from the joint surfaces. This creates contact between the bone surfaces allowing them to heal together. In some situations it is recommended to use bone graft or other artificial bone substitutes to promote bone healing. Bone graft might be taken from your foot, from just below the knee or from near the hip. In rare cases donor bone is needed from a “bone bank”.
The bones of the ankle joint are then held in place using metalwork which might be screws, metal plates or staples. These are inserted either through the same incision or through separate 1cm incisions. The surgeon takes x-rays during the operation to confirm the alignment and the position of the metal fixation implants.
You will usually be able to get home the next day although sometimes you might need longer. You would go home with your ankle either in cast or a moonboot. There will be some swelling and you will need to keep your foot elevated on a footstool in the early recovery period.
Usually you would be unable to bear weight for the first six weeks. You would walk either on crutches or using a knee walker. A knee walker is like a scooter which allows you to walk loading both legs keeping your hands free. They can be purchased or hired on a weekly basis. Some people can have a specially adapted cast known as a “Bohler walker” which allows you to walk on the cast while keeping the weight of the operated foot.
You would be seen in clinic at the two week mark to check the wounds and again at various intervals, usually at 6, weeks, 12 weeks and 6 months for x-rays to check on the progress of the bone healing.
After 12 weeks you would come out of the boot and start to mobilise freely. It can take another three months for the strength to fully return. Your walking distance will steadily increase over that time. You can return to driving when you can safely use the pedals in the car (although if the surgery is on the left ankle and your car is an automatic you can usually drive while you are still in the boot). You would gradually return to all your normal activities over that time.
Once the bones have healed an ankle fusion is strong enough to withstand all normal activities. You can normally return to more physically demanding jobs or to sports such as cycling and skiing. Some people will be able to return to running.
Most people will not walk with a limp after fusion of only one joint. If more than one joint has to be fused then gait can be affected. The fused joint will no longer move. For some people with problems in other joints of the foot this will be more restrictive. For most people in whom the problems are confined to the one joint, the remaining joints will continue to move normally meaning the whole foot remains very mobile.
All surgery carries risks, and fusion 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: