Osteoarthritis of the Ankle

By Linda Rath | March 19, 2024 

Ankle osteoarthritis (OA) isn’t common, although it’s not clear how many people have it. Estimates range from 1% to 12% of people with OA are affected in an ankle, but it may be more because there’s little research on this type of arthritis — 10 times less than on knee OA, according to Arthritis Foundation findings. 

Unlike OA in other joints, an arthritic ankle almost always develops after an ankle injury, especially a severe strain or fracture that happened years or even decades earlier. In about 90% of cases, ankle osteoarthritis causes are past traumas, compared to 2% to 10% of knee OA cases. An ankle injury can damage cartilage directly, make the joint less stable or change how it works (joint mechanics). 

Excess weight, which puts added pressure on the ankles and other weight-bearing joints — four pounds of pressure for each extra pound of weight — and repeated high-impact stress also play a part. Ankle cartilage is half the thickness of knee cartilage, leading to more force on the ankle joint. 

Patients who have ankle osteoarthritis are typically about 14 years younger when they’re diagnosed than people diagnosed with osteoarthritis in other joints, and they progress to end-stage disease more quicky. An arthritic ankle can cause problems in other joints, too, especially the hips and knees as they try to compensate for an unstable ankle.

If you have a history of ankle injuries — maybe when you played high school basketball or served in the military — your ankle pain could be OA. Arthritic ankle pain may not be felt in the joint itself, but in the middle or back of the foot. It can vary from a dull ache to sharp, stabbing discomfort. The pain may come and go or be low level and chronic, punctuated by flares. Other osteoarthritis ankle symptoms include:

• Swelling
• Stiffness and loss of flexibility
• A crunching or popping sound when flexing or pointing the toe

Magnetic resonance imaging (MRI) is considered the best way to diagnose ankle arthritis because it can detect damage to ligaments and cartilage — problems that don’t normally show up on X-rays. The drawbacks: MRI is expensive, not readily available in some places and may miss early signs of OA, especially in the heel joint.

There are no clinical guidelines for ankle osteoarthritis treatment. Most approaches are based on arthritis treatments for other joints and may not be particularly applicable to ankles. Still, certain conservative measures and lifestyle changes have been shown to help.

• Physical therapy. The goal of physical therapy is to improve range of motion and strengthen muscles that support the ankle, including calf muscles. Most insurance plans and Medicare cover at least some physical therapy costs. Depending on your insurance, you may be limited to a certain number of physical therapy sessions.
• Low-impact exercise. Regular exercise is essential for any type of arthritis, including ankle osteoarthritis. If you’ve always been a hard-charging athlete, consider lower-impact workouts like swimming, walking and biking.
• Weight loss. There’s little research about the effect of weight loss on ankle OA, although some experts say that dropping even 10 pounds can reduce pain considerably. A 2021 British study that simulated weight loss from 30 BMI (defined as obese) to 25 BMI (normal weight) reported a 32% decrease in ankle pain. Using BMI to define obesity is controversial, but the main takeaway is that modest weight loss reduced ankle pain by more than one-third.
• Supportive footwear and orthotics. The right shoes can go a long way toward relieving ankle pain. Look for high-top shoes and boots that help stabilize the ankle joint. Your doctor may also recommend orthotics — special shoe inserts that provide support, help control joint motion and improve ankle function. The most common orthotics combine a soft upper for cushioning and shock absorption and a rigid bottom for support. Custom inserts can be expensive and aren’t always covered by insurance. Some podiatrists may customize off-the-shelf inserts to address your needs.

Medications

• Nonsteroidal anti-inflammatory drugs (NSAIDs). Pain relievers like ibuprofen and naproxen are among the first drugs prescribed for arthritis pain, and they offer temporary relief for some people. NSAIDs also come with some potentially serious side effects, including GI bleeding and ulcers, an increased risk of heart attack and stroke, and liver and kidney damage. A topical NSAID gel applied to the skin may be just as effective with fewer side effects. Keep in mind that the benefits of pain relievers often diminish over time, and they treat only symptoms, not the underlying problem.

Injections

• Hyaluronic acid. Hyaluronic acid (HA) is a substance that occurs naturally in the body, acting as a lubricant in joints and helping prevent bones from grinding toother. Hyaluronic acid injections are often used to relieve osteoarthritis pain, especially in the knee joints, but whether it’s effective for ankle pain isn’t clear.  A 2023 systematic review of seven clinical trials found little evidence that HA is effective at relieving ankle OA pain. Other research has shown that HA is safe and can provide pain relief for up to six months or longer. Italian researchers looked at the use of a hyaluronic patch boosted with bone marrow aspirate to repair damaged ankle cartilage. They followed 101 patients for 10 years, finding a significant reduction in pain, although gains started to decrease after five years.
• Platelet rich plasma (PRP). Derived from a person’s own blood, PRP has been used to grow hair, treat wrinkles and heal damaged tendons, ligaments, muscles and joints. The benefits don’t come from PRP itself but from its ability to kickstart the body’s own healing process. Injections into arthritic knee joints have successfully relieved pain and improved function, but results of studies about ankle arthritis have been mixed. PRP is safe, and in a recent meta-analysis of 30 randomized controlled trials, PRP proved more effective for knee OA than placebo, corticosteroid injections and hyaluronic acid shots. The main drawback: Traditional Medicare and most private insurers don’t cover it, so you’ll have to pay the full cost out of pocket.   

Surgery
Most surgical procedures are considered a last resort for ankle osteoarthritis, and all have drawbacks. According to the Arthritis Foundation and American Orthopaedic Foot and Ankle Society:

• Arthrodesis, which fuses bones in the ankle, erases pain by preventing ankle movement but often leads to arthritis in surrounding joints.
• Ankle replacement surgery isn’t effective for many patients, and because it isn’t long-lasting, can mean one or more revision surgeries. These operations are more challenging to perform and usually less successful than the original procedure.
• Joint-sparing procedures should be tried before joint-destructive procedures like ankle replacement surgery, especially in younger, active patients.