When conservative treatments for arthritis fail to satisfactorily relieve pain in an affected ankle, it may be time to consider joint surgery. It's important to learn about the various types of joint surgery and understand your options. Ankle fusion, also known as ankle arthrodesis, is one surgical option.
Ankle Fusion Explained
Three bones make up the ankle joint -- the lower end of the tibia (shinbone), the fibula (small bone of the lower leg), and the talus (bone that fits into the socket formed by the tibia and fibula). The talus rests on the heelbone. Articular cartilage lines the inside of the ankle joint. Normally, the cartilage is about a quarter of an inch thick. If injury occurs, or if the cartilage is damaged by arthritis, pain can be quite severe.
An ankle fusion is a surgical procedure that removes the surfaces of the ankle joint for the purpose of promoting a fusion between the tibia and the talus. "Fusion" refers to bones growing together. Fusion is not only performed on the ankle, but also on other joints in the body that are severely painful.
There are a couple of methods for the ankle fusion procedure, but the goal of each is the same -- to fuse the ankle joint.
The Open Method
- an incision is made to open the skin and access the joint
- the joint is opened
- a surgical saw is used to remove articular cartilage surfaces
- once the articular cartilage is removed, the body will heal by fusing the joint
- the cuts must be precise so that the bones are at the proper angle when they are brought together to fuse
- screws and sometimes plates are used to hold bones together until they fuse
- usually screws or pins are under the skin and not removed
- in some cases, an external fixator (pins on outside of skin) can be used
The Arthroscopic Method
This method employs an arthroscope. Through a small incision, the arthroscope (which contains a tiny TV camera) is inserted into the ankle joint. Using other instruments, cartilage is removed through the tiny incision while the arthroscope is used to observe the progress of the procedure. After the surfaces are prepared, screws are placed to hold bones together until they heal. This method is not much different than the open method other than smaller incisions are used.
Who Is a Candidate for Ankle Fusion?
Patients who have severe ankle damage from arthritis or past injury may be candidates for ankle fusion. Candidates usually have ankle pain that is unrelenting even after being treated with medications or other treatment options. When pain is so severe that it interferes with walking and usual daily activities, it's time to discuss the option of ankle fusion with an orthopedic surgeon.
The Benefits and Risks of Ankle Fusion
The goal of ankle fusion is to relieve pain and restore function to the affected ankle. Though some may be concerned that there is motion lost with a fusion, many patients tend to forget that they have already lost range of motion in the severely damaged ankle.
A fusion should last a lifetime compared to an ankle replacement, which may wear out at some point.
Consider your goals when deciding if ankle fusion is the best option for you.
- pain relief
- the fused joint is stable again
- patients will be able to bear weight on the fused joint without pain
- ability to walk and perform usual activities is restored
- ankle replacement may still be a better option for certain patients (very active individuals)
- there is loss of flexibility and motion with a fused joint
- slight possibility of wound healing complications
There are potential complications, as with any surgery. There may be risks associated with anesthesia, as well as risk of nerve or blood vessel injury, post-op infection, nonunion (bones don't fuse), and malunion (bones heal in the wrong position). If nonunion or malunion occurs, another surgery may be required.
Recovering from Ankle Fusion
The operated leg is wrapped in a padded plaster cast after surgery. After 2 weeks, a shorter cast replaces the padded plaster cast. The patient cannot bear weight on the ankle for 8 to 12 weeks, at which time there should be x-ray evidence of fusing.
Keeping your leg elevated is important to prevent or reduce leg swelling. Crutches are usually necessary while the patient refrains from putting weight on the ankle. X-rays, taken often, will show if the fusion is becoming stronger and solid. At that point, the patient is allowed to put more weight on the ankle as she walks. Some patients may want special shoe inserts to help them walk more normally, while many simply wear flat shoes and do just fine.
A Patient's Guide to Ankle Fusion. eOrthopod. Medical Multimedia Group, LLC. July 22, 2002.