ankleimplantArthritis patients are quite familiar with creaky knees and with surgery to replace them when they become too debilitated to function. A 2013 report from Brigham and Women’s Hospital in Boston estimated that more than half the adults in the U.S. diagnosed with knee osteoarthritis will undergo a total knee replacement, and that 4 million Americans over age 50 have had knee replacement surgery. The Centers for Disease Control and Prevention reports that more than 700,000 knee replacement surgeries were performed in 2010; there’s speculation that number could rise into the millions by 2030. Chances are, if you’re in the AARP demographic, you’ve had knee replacement surgery or know someone who has.

Ankle replacement is another story. According to an article in the New York Times, only 4,400 Americans underwent ankle replacement surgery in 2010. While the number has been growing, ankle replacement is not performed anywhere near as frequently as knee replacement.

It’s less common, because it’s more complicated and, possibly, because the results haven’t been as remarkable. That presents a challenge to physicians and medical researchers.

Recently the Hospital for Special Surgery (HSS) in New York City released information about a new ankle implant that seems to be an improvement over existing ankle replacement prostheses. Dr. Jonathan Deland, co-chief of the Foot and Ankle Service at HSS, consulted on the development of the new implant, which is said to more closely replicate the ankle’s natural motion and its shape and curvatures. Even the implant surgery itself is easier on the joint. The incision on the side of the ankle, as opposed to the front, “will generally cause less disruption to the soft tissues surrounding the ankle joint,” Dr. Deland says, “and it allows for the replication of curved bone surfaces like those in a normal ankle.”

Treatment for ankle arthritis starts with a change in footwear, opting for closed shoes that lace up above the ankle and have cushioned soles. If that doesn’t ease the pain, a brace might be recommended. Fusion surgery or arthrodesis, which fuses two raw bone surfaces together, is a common “next step” for treatment of ankle arthritis. It relieves pain but ultimately restricts ankle motion.

Think about the way your ankle moves—or should move. It flexes, it rotates, it bears your weight, it goes through  broad range of motion every time you take a step. There are so many motions to be accommodated and replicated to restore full use of the ankle; of course the development of an ideal ankle prosthesis will take time. And even then, ankle replacement surgery is not recommended for everyone. Dr. Deland says that candidates for ankle replacement are people who have undergone “conservative” treatments—such as rest and bracing—and still not found relief. They should be age 50 or older, they must have good bone quality and foot alignment, and they must not have underlying health problems that would impede healing.

Is ankle replacement in your future? If you suspect you might be a likely candidate it’s worth watching developments in treatments and devices. Steps forward are being made every day.