Ankle arthritis leads to pain and swelling in the ankle joint. Symptoms are often aggravated by standing and walking, and patients often walk with a limp. Ankle arthritis commonly results from a history of trauma to the ankle; either a severe ankle injury, such as a bad ankle fracture, or a series of recurrent injuries to the ankle. However, ankle arthritis may develop from other causes, such as uneven loading of the ankle joint due to an alignment deformity; inflammatory arthritis, such as rheumatoid arthritis; crystal arthritis, such as gout, or secondary to a serious joint infection. Patients with severe ankle arthritis will often have limited ankle motion and may have a grinding sound when they move their ankle joint. Ankle arthritis is commonly associated with loss of cartilage from the ankle joint, which will show up on a weight-bearing ankle x-ray (Figure 1). Non-operative treatment is designed to improve function and decrease pain, and is based on: limiting the amount of loading through the ankle joint (weight loss, activity modification, cane); controlling the symptoms (anti-inflammatory medication, pain medications); and decreasing ankle joint movement (ankle bracing, rocker-bottom shoewear). Operative treatment may be helpful if non-operative treatment is unsuccessful. Common operative treatments include cleaning out (debriding) the ankle joint if the ankle arthritis is not severe, or ankle fusion for patients with severe arthritis. Ankle replacement may be an option for older patients who are not excessively active or for patients with other major foot fusions.
Ankle pain, stiffness and swelling are characteristic symptoms of ankle arthritis. Pain is often aggravated by activities, such as standing and walking. “Start-up” pain, such as when a patient has pain and stiffness in the ankle after sleeping or sitting in one spot for a while, is also a common complaint. When this occurs, it often takes the patient a few minutes (or longer) to “warm-up” the ankle. The ankle will tend to swell more as the day progresses, particularly if there is increasing activity. Pain is often experienced throughout the ankle, although it may be more noticeable at the front of the ankle if large bones spurs have formed. Ankle arthritis occurs when there has been damage to the joint cartilage that normally covers the ends of the bones of the ankle joint. Loss of cartilage leading to ankle arthritis can occur from a variety of causes including:
- Major ankle trauma (such as an ankle fracture). This is the most common cause of significant ankle arthritis and, therefore, a history of an ankle or lower extremity fracture often increase the risk of developing ankle arthritis.
- Many small to moderate recurrent injuries to the ankle joint over time (such as ankle instability and recurrent ankle sprains)
- Abnormal ankle joint loading leading to a wearing of the cartilage in one area of the ankle (such as occurs in people with long standing marked flatfoot deformities or other conditions causing abnormal alignment of the ankle or lower extremity)
- Inflammatory arthritis such as rheumatoid arthritis. In this situation, an inflamed joint lining can eventually damage the joint cartilage.
- Crystal arthritis such as gout or pseudo-gout which leads to inflammation in the joint and may eventually lead to destruction to the joint cartilage.
- Infectious arthritis can cause ankle joint damage if bacteria in the joint lead to destruction of the joint cartilage.
On physical examination, the patient will often have ankle swelling relative to the opposite ankle. There is likely to be a restriction in ankle motion, which may be associated with cracking or popping. Patients may walk with a noticeable limp.
Ankle arthritis can be diagnosed on plain ankle x-rays (Figure 1). X-rays performed with the patient weight bearing will demonstrate:
- Loss of joint space. This correlates with the loss of joint cartilage.
- Bone spurs. Bone spurs are known as “osteophytes” and they often occur as the body’s natural response to arthritis.
- Increased bone density at the joint line. As a result of increasing loading forces due to the loss of cartilage, the bone often thickens at the level of the joint line, leading to “subchondral sclerosis.” This appears as increased whiteness in the bone on x-rays.
In subtle cases, or if there are other questions that need to be answered, it may be necessary for the treating doctor to order an MRI or a CT Scan of the ankle and hindfoot.
There are non-operative and operative treatments for ankle arthritis. The goals of treatment are to minimize pain and discomfort and to improve function. The type of treatment that is most appropriate will depend on the patient’s symptoms, the extent of the ankle arthritis, other treatments tried, and the patient’s preferences. Often, non-operative treatment can be successful in significantly decreasing symptoms. Many of the non-operative treatment approaches can also be helpful in conjunction with surgery.
- Limit the force going through the ankle joint;
- Limit the movement through the ankle joint and/or;
- Minimize the pain response.
Non-operative treatments may include:
- Anti-Inflammatory Medication (NSAIDs)
- Comfort shoes with a stiff sole and a rocker-bottom contour to disperse the force more evenly past the ankle
- Brace to limit ankle motion
- Cushioned shock absorbing orthotic. A soft, shock-absorbing orthotic may help to dissipate some of the force that would normally go through the ankle with each step.
- Cane used in the opposite hand to decrease the force that is loaded through the ankle joint with each step.
- Weight loss. For every 5lbs of weight loss there is 10-15 lbs less force going through the ankle joint with each step.
- Physiotherapy or Home exercise programs. Exercises designed to keep the joints of the hindfoot moving and the muscles that control the ankle strong can be helpful.
- Activity modification. Looking for creative ways to spend less time standing, take fewer steps, and avoid aggravating activities can make a big difference in symptoms.
- Ankle debridement (Cleaning out of the ankle joint by removing bone spurs). In patients with mild to moderate arthritis, especially those with pain at the front of their ankle and limitation in their ability to bring their foot towards their shin (Limited dorsiflexion), ankle debridement can be very helpful. This can be done arthroscopically, although if the bone spurs are large, it is sometimes easier to do it by opening up ankle joint.
- Ankle Fusion (Ankle Arthrodesis). For patients with painful end-stage arthritis, (no or very little cartilage remaining), an ankle fusion can often improve a patient’s symptoms significantly. The painful ankle joint articulation is removed by fusing the two main bones of the ankle joint (the tibia and talus) together so they form one bone. While an ankle fusion stops movement through the ankle joint, movement through the remaining joints in the foot provides a significant amount of the movement needed for walking normally.
- Ankle Replacement (Ankle Arthroplasty). Ankle replacements can produce significant pain relief, however, as the biomechanics of the ankle joint will predispose to failure of the prosthesis over time, ankle replacements are often reserved for older patients who are relatively less active. They may be appropriate for patients that have other fusions in their hindfoot as well.
- Realignment of Deformities. Occasionally, ankle arthritis will be caused by a deformity below the ankle joint (ex. severe flatfoot) or above the ankle joint (ex. old tibia fracture that has healed crookedly), which leads to a concentration of force in a localized area of the ankle joint (and subsequent wearing out of cartilage in this area). In some situations (ex. relatively young patients), these patients may be candidates for surgery (ex. a calcaneal osteotomy), which corrects their deformity and thereby redistributes the load to an area of the ankle joint where the cartilage is still preserved.
Potential Surgical Complications: Any surgical procedure may lead to a surgical complication. Procedures to address ankle arthritis are no exception!
Less Common, Experimental, or Unproven Procedures for Ankle Arthritis
- Distraction Arthroplasty (Arthrodiastasis). It has been suggested that distracting the ankle joint for a few months by placing a ringed external fixator (a device with pins going through the bones above and below the ankle joint) may help patients with significant ankle arthritis. It is unclear exactly how this may help patients, although there have been some reports of success with this treatment. Unfortunately, widespread success with this procedure has not yet been documented.
- Total Ankle Allograft. In a few centers, surgeons have replaced the entire arthritic ankle joint with a “healthy” ankle joint taken from a recently deceased human donor in a procedure akin to an organ transplant. There was great excitement in the foot and ankle community when this procedure was described a few years ago. Unfortunately, it does not appear as if the intermediate and long-term results of this type of procedure have produced the desired results.
- Interposition Arthroplasty. Placing a soft-tissue graft inside the ankle joint (also known as “Total Ankle Replacement with No Metal”) is designed to pad the joint, while still maintaining some ankle movement. This is known as an interpostional (in between) arthroplasty (joint replacement). In the past, this type of procedure has been performed in many joints of the body (hips, knees, wrists, etc.) and it has not met with any long-term success. There is no reason to expect the results in the ankle joint will be any different.