Severe arthritis of the ankle joint is the result of progressive wearing down of the articular cartilage cushion that lines the joint, ultimately creating bone-on-bone grinding. End-stage arthritis results in pain, combined with loss of function and mobility – severely limiting normal activity. When this end stage is reached and non-operative options (such as medication, injections, and bracing) have been exhausted, patients are presented with two methods of surgical treatment.
Traditionally, when patients develop end-stage arthritis, they have undergone a fusion procedure, creating raw bone surfaces which are held together with metal plates and/or screws until the bone surfaces unite or fuse. The goal of fusion is to place the ankle in a correct fixed position; pain is relieved at the expense of loss of motion at the ankle joint. The ankle is generally cast for approximately eight to twelve weeks (until the fusion is solid).
Because an ankle fusion results in loss of motion, the joints surrounding the ankle flex and extend to compensate. While this allows most fusion patients to walk with a minimal limp or without a limp, the primary concern is that these adjacent joints run the risk of becoming arthritic themselves.
Total Ankle Replacement
Total ankle replacement is a relatively new procedure, the modern, accepted design having only come into widespread use in the late 1990’s. This procedure relies on replacement of the arthritic surfaces with a man-made implant that is composed of two or three components that glide against each other using low-friction materials. The primary benefit is pain relief with retained ankle motion.
Total ankle replacement requires a shorter immobilization period and has been shown to provide a functional range of motion in the ankle, allowing patients to actively engage in daily tasks (and low-impact sports). More importantly, total ankle replacement results in a smaller amount of stress upon the surrounding joints, reducing the risk of arthritis in those areas as well.
There are some difficulties in creating an effective implant for total ankle replacement, and they can be largely attributed to the complex motion at the ankle joint. The center or rotation of the ankle joint does not remain constant through the course of motion. The “trick” is to allow for rotational forces while moving through a range of flexion and extension.
The bottom line is that although nobody wants to live with severe ankle arthritis there are several surgical options available to improve quality of life in people that have reached the point where non-surgical methods of treatment are no longer effective. Ankle fusion has been the traditional “gold standard” treatment option for end-stage ankle arthritis. Yet, in the last two decades, total ankle replacement has become an effective alternative for many patients. It is important to consult a foot and ankle specialist who understands the factors that influence the condition of the ankle and is able to recommend the best option for relief of arthritic ankle pain.