Ankle Replacement
Total ankle replacement (arthroplasty) is one of the two surgical options used to treat severe form of arthritis in the ankle joint. It involves removing the worn out joint surfaces and replacing them with metal prostheses separated by a polyethylene component.
What are the benefits of ankle replacement?
The main objective of surgery is to alleviate pain and improve function and quality of life. As opposed to an ankle fusion, the replacement is aimed to maintain the range of motion that helps to regain the normal walking pattern.
The Procedure
Total ankle replacement is a major procedure. Not every patient or every ankle is suitable for undergoing a replacement surgery. The procedure is performed either under a general or a spinal anaesthetic and often requires a regional nerve block to achieve optimum pain relief after surgery. The metal components are fixed with the bones without the use of bone cement, hence the ankle is placed in a temporary plaster cast. Usual hospital stay is approximately 2-3 days and requires a thorough assessment by the physiotherapist. You are allowed to mobilise with the use of crutches (or a walking frame) with toe-touch weight bearing.
Recovery
After going home, elevation of the ankle and pain killer medications are recommended in the first few days. You are likely to be given heparin injections (depending on surgeon’s preference) for 6 weeks to minimise the risk of blood clots. Wound is on the front of the ankle and sutures are removed in 2 weeks time. Wound dressings are not disturbed until you are seen in clinic at 2 weeks stage.
At that stage, the ankle is placed in a walker boot and weight bearing is increased gradually. At 6 weeks you will be reviewed in the clinic for x-rays and will start to mobilise out of the boot. From weeks 6-12, you can wean off the crutches and start to use you normal shoe wear and will be referred for physiotherapy.
The normal shoes may not fit well as the swelling can take several weeks to improve. A good level of recovery may take 3-6 months and in some cases even longer. You will be followed up on regular basis at 3, 6 and 12 months and then on yearly basis for routine reviews and xrays.
What complications can occur after surgery?
Potential risks and complications after ankle replacement surgery include infection, wound problems, bleeding, blood clots in the leg or lungs (deep vein thrombosis, pulmonary embolism), fracture during or after surgery, ongoing pain, stiffness, damage to nerves and vessels, numbness around the scar, chronic regional pain syndrome, loosening of the implants, long-term failure, further surgery, and anaesthetic risks. These potential problems occur in a small percentage of cases but the risk increases with the presence of certain medical conditions and the use of certain long-term medications.
How long is the new ankle going to last for?
The current research suggests that a satisfactory result of an ankle replacement would result in maintaining a good function of the joint in 80-90% cases at 10 years after surgery. However, the survival of the artificial joint depends on various factors. It is important to know that the ankle replacement is not as well-established as the hip or the knee replacements and is still going through its evolution with newly designed implants during the recent years. Hence the expected results may not be as satisfactory as hip or knee joint replacements.
