Total Ankle Replacement
By Barry Mulshine, M.D.
Board Certified Orthopedic Surgeon
Arthritis is a common cause of chronic, activity-related pain around the ankle joint. Although arthritis more often involves the hip or knee joints, when the ankle is affected, this can significantly interfere with everyday activities.
Arthritis may be broadly categorized into two types: inflammatory and degenerative. Inflammatory arthritis includes rheumatoid arthritis, gout, and psoriatic arthritis. Typically causing episodes of pain and swelling, these are often treated with medications, but surgical treatments are sometimes indicated. Degenerative arthritis, also called osteoarthritis, or wear-and-tear arthritis, gradually worsens over time. Traumatic arthritis presents much like degenerative arthritis, but can develop following a fracture or other injury involving the ankle joint.
Early on, ankle arthritis will cause symptoms such as pain and swelling associated with increased activities. Over time, the symptoms may persist with everyday activities and even at rest. Sometimes mechanical symptoms, such as popping, grinding, or “giving out” may develop. As the arthritis worsens, the ankle joint may lose its range of motion. In more severe cases deformity can occur, and the foot may begin to deviate to one side or the other.
Treatment of Ankle Arthritis
The initial treatments for arthritis of the ankle are similar to those used to treat arthritis in any joint. Acetaminophen, anti-inflammatories, ice, or activity-modifications may help to relieve some of the pain. If the symptoms persist consideration may be given to injections or bracing.
If pain from arthritis persists despite medications, an injection of cortisone into the ankle joint may be helpful. This can be done in the office with a topical anesthetic. The benefits can be quite variable. Some patients may experience significant pain relief that lasts for several months or more, while others may find only partial improvement for a few weeks. Generally, it is not advised to repeat injections more often than two or three times per year.
Viscosupplementation injections, such as Hyalgan, Synvisc, or Supartz, which are commonly done for knee arthritis, have not been shown to be as effective for the ankle, and are generally not covered by insurance.
Another non-surgical treatment option for ankle arthritis is the use of a brace. There are numerous types of ankle braces. On one end of the spectrum are flexible, lightweight braces. These are relatively inexpensive and easy to use with shoes, but may be less effective since they still allow some motion of the ankle. On the other end of the spectrum are custom-made AFOs (ankle-foot orthosis) that better immobilize the ankle, and are therefore more effective for pain relief. However, being more bulky and cumbersome, many patients do not tolerate this type of brace.
As the severity of the arthritis progresses with time, surgical treatments may become warranted. There are three main surgical options: removal of osteophytes (spurs), ankle arthrodesis (fusion), and total ankle replacement.
Sometimes arthritis will produce bone spurs around the ankle joint that can limit the motion of the joint. In cases where this causes a significant loss of motion, and pain only at the end-point of motion, removing these spurs may be worthwhile. Often this can be done arthroscopically through two small puncture holes. This will not cure the underlying arthritis, but will alleviate symptoms caused by the prominent spurs themselves. This procedure can be done on an outpatient basis, and would allow for immediate weightbearing.
Ankle Arthrodesis (Fusion)
An arthrodesis solves the problem of a painful joint by, in essence, eliminating the joint. The goal is to fuse the tibia and talus bones together in the same way a fracture heals together. This eliminates the pain from arthritis, but sacrifices motion of the joint. Patients are generally surprised how much “ankle-like” motion remains from the adjacent joints in the foot, and how well they can walk with a fused ankle. In many cases the surgery can be done arthroscopically through small puncture incisions. A prolonged period of non-weightbearing is required, but once the fusion has healed, the pain relief is permanent.
Total Ankle Replacement (TAR)
The goal of ankle replacement surgery is to resurface the joint with metal implants and use a plastic spacer to eliminate the painful grinding of the arthritic joint while preserving the motion. Early generation TAR implants tended to loosen prematurely, but the implant technology has been steadily improving over the past decade. Some designs have shown 80-85% survival at 10 years. Given the widespread success of knee and hip replacement surgery, patients with ankle arthritis typically find this option very appealing. Indeed, patient satisfaction scores are quite high after TAR. Unfortunately, many patients are not good candidates for this surgery. Patients with severe ankle deformities should not undergo TAR. Diabetics and smokers would have higher risks of wound healing problems, and young, active patients would tend to loosen or wear out the implants.
Arthrodesis vs. TAR
When considering surgical treatment for ankle arthritis, it is very important to match the right patient to the right procedure. Patients who already have a fusion of the opposite ankle, or have fusions of other joints in the foot would likely have better function with an ankle replacement. On the other hand, patients who are smokers, diabetic, very active, or significantly overweight would be better candidates for ankle arthrodesis.