Total Ankle Replacement Infections

Ankle arthritis affects approximately 1% of the population. Traditionally, surgery to fuse the ankle joint, called ankle arthrodesis (AA), has been the go-to treatment for relieving pain and correcting deformities caused by ankle arthritis. However, AA can sometimes lead to arthritis in neighboring joints, resulting in more discomfort and limited movement. Additionally, successful fusion doesn’t always occur in about 10% of cases. Total ankle replacement (TAR) is becoming increasingly popular as an alternative to AA, especially when arthritis affects other foot joints as well. TAR aims to maintain ankle mobility better, potentially improving overall function and safeguarding surrounding joints from arthritis.

However, the choice between AA and TAR isn’t straightforward, and each has its risks and benefits. Some studies suggest that TAR may have more complications compared to AA.

One significant complication of TAR is periprosthetic joint infection (PJI), which often requires further surgical intervention, such as implant replacement, ankle fusion, or even amputation.

The risk of developing PJI after TAR varies widely, ranging from less than 1% to over 20%. Treating ankle infections is particularly challenging due to the ankle’s delicate soft tissues, making infections harder to manage. The primary goals in treating PJI are to eliminate the infection and restore pain-free function to the leg. Surgical options for TAR-related PJI include cleaning the infection and retaining the implant (DAIR), replacing the implant in one or two stages, or resorting to amputation. Following TAR replacement, additional surgeries, such as a repeat TAR or ankle fusion, may be necessary.

Unfortunately, there’s limited information available on ankle implant infections compared to hip or knee replacements. Because ankle infections are rare, there are only a few small studies, and they often lack comprehensive information about causes, bacterial types involved, treatment approaches, and post-treatment outcomes.

Total ankle replacement is becoming increasingly common for treating ankle osteoarthritis (OA), but along with its rising popularity comes an increase in complications.

For this study around 3.8% of ankle implants were found to have periprosthetic joint infections (PJIs), a rate similar to what other studies have reported. Among studies with at least 50 implants, infection rates after ankle replacement ranged from 2% to 8.5%.

PJIs occurring after ankle replacement surgery are less frequent in the early stages compared to later stages. Our review identified 53 early PJIs compared to 156 chronic cases.

Various treatments are available for infected ankle replacements, including cleaning the infection (DAIR), replacing the plastic components, or removing the entire implant.

Cleaning the infection through irrigation and debridement is often performed shortly after surgery, especially if only the plastic component needs replacement. However, there’s limited data on its effectiveness for ankle replacements compared to other joints. Some studies have indicated that cleaning the infection alone may not be very successful, with all cases treated this way experiencing reinfection. Other treatments, such as replacing the entire implant, might offer better results, but further research is necessary to confirm.

Recent findings suggest that cleaning the infection and replacing the plastic components of the ankle implant may be slightly more effective than just cleaning the infection alone. This is because these steps can lead to more thorough removal of infected tissue. In cases where patients had infections resulting from bacteria spreading through the bloodstream, both cleaning the infection and replacing the plastic components helped retain the implants in position.

However, the success of this procedure can vary. Some studies have shown a success rate of around 46% when the infection was treated quickly with cleaning and replacing the plastic parts. But if patients had symptoms for a longer time or if the bacteria were resistant to antibiotics, the success rate decreased.

When the infection couldn’t be cleared with cleaning and replacing the plastic parts, the implants often had to be removed in two stages. This means taking out the implant, treating the infection, and then putting in a new implant later. However, this approach might not work as well for ankle implants as it does for hip and knee implants because the ankle has less blood flow and more problems with wound healing.

Sometimes, instead of putting in a new implant, the ankle might be fused together with screws or nails. This is often done when the patient’s overall health is not good, or if there are problems with the blood vessels or soft tissues around the ankle. However, ankle fusion can lead to other issues like differences in leg length or problems in nearby joints.

Overall, if ankle replacement fails and needs to be fixed, the success rate of ankle fusion is around 89%. But some studies have shown that patients might have more pain and less function after ankle fusion compared to when they first had the procedure.

Revision surgery to fix problems with ankle replacement implants has been successful in some cases. Doctors often use special replacement parts designed specifically for revision surgery. While some studies have shown that revision surgery after a failed ankle replacement can have similar results to the first surgery, other studies have found that patients often have ongoing pain even after revision surgery, and in some cases, amputation may be necessary. However, not many studies have looked closely at how well patients can move and function after revision ankle replacement surgery.

In a few cases, doctors have used a temporary cement spacer to treat infections in ankle replacements. Although this can sometimes work well, it’s usually only considered when patients don’t have any symptoms after the spacer is put in, or if they’re not healthy enough for more surgery, or if the tissues around the ankle are damaged. However, there’s a risk that the spacer could become infected over time, just like the original implant did.

In very difficult cases, amputation below the knee may be recommended. This is usually a last resort when other treatments haven’t worked, and it’s done to remove the infected tissue and stop the infection from spreading further.

In summary, while ankle infections after replacement surgery are rare, they can be very serious. Doctors usually try to treat them by cleaning out the infection and giving antibiotics for several weeks. If possible, a two-stage surgery to remove and replace the implant may be done. However, more research is needed to better understand how to treat these infections and improve outcomes for patients.

A seasoned orthopedic surgeon and foot and ankle specialist, Dr. Mohammad Athar welcomes patients at the offices of Complete Orthopedics in Queens / Long Island. Fellowship trained in both hip and knee reconstruction, Dr. Athar has extensive expertise in both total hip replacements and total knee replacements for arthritis of the hip and knee, respectively. As an orthopedic surgeon, he also performs surgery to treat meniscal tears, cartilage injuries, and fractures. He is certified for robotics assisted hip and knee replacements, and well versed in cutting-edge cartilage replacement techniques.
In addition, Dr. Athar is a fellowship-trained foot and ankle specialist, which has allowed him to accrue a vast experience in foot and ankle surgery, including ankle replacement, new cartilage replacement techniques, and minimally invasive foot surgery. In this role, he performs surgery to treat ankle arthritis, foot deformity, bunions, diabetic foot complications, toe deformity, and fractures of the lower extremities. Dr. Athar is adept at non-surgical treatment of musculoskeletal conditions in the upper and lower extremities such as braces, medication, orthotics, or injections to treat the above-mentioned conditions.