When to Consider Total Ankle Replacement for Patients With End-Stage Ankle Arthritis

By Sara Lyn Miniaci-Coxhead, MD, MEd

Total ankle replacement (TAR) was introduced in the 1970s, but initial design flaws led to significant failures. As a result, ankle arthrodesis continued to be the gold standard in treating ankle arthritis.

In the 1990s and early 2000s, the current generation of TAR implants was approved by the U.S. Food and Drug Administration and brought to market. These implant designs produced much better outcomes and survivorship rates, and mainstream use of TAR increased. Between 1998 and 2010, use of TAR increased sixfold while ankle arthrodesis remained constant.

Indications and contraindications

With TAR now a viable option for patients, surgeons must be aware of both the indications and contraindications for the procedure. As with total hip and knee replacement, patients with end-stage arthritis are candidates for the surgery, assuming they have not had success with conservative treatments such as activity modification, bracing, anti-inflammatories, injections and shoe-wear modifications.

Conventionally, the ideal patient for TAR has been thought to be older than age 50 and a low-demand individual with minimal radiographic deformity of the ankle. However, with newer implants and techniques, severe deformity is no longer a contraindication.

Absolute contraindications to TAR are:

• Active infection
• Charcot arthropathy
• Severe peripheral vascular disease
• Inadequate soft tissue coverage

Relative contraindications are:

• Peripheral neuropathy
• Osteoporosis
• Severe malalignment
• Avascular necrosis of the talus

In evaluating a patient for TAR, a medical history is recorded, and a standard physical is completed, paying close attention to alignment and neurovascular exam. Weight-bearing foot and ankle films are standard to assess the alignment of the ankle joint as well as the status of the surrounding joints. Often, advanced imaging in the form of a CT scan is obtained to better evaluate the bony architecture.

A detailed discussion with the patient should include the risks and benefits of both TAR and ankle arthrodesis.

Procedure and recovery

The majority of ankle arthroplasties are performed with an anterior ankle approach, although there is one implant on the market that requires a lateral transfibular approach. The surgery typically takes two to three hours and can be performed as an outpatient procedure, although many patients spend one night in the hospital.

Patients are typically non-weight-bearing for three to six weeks after surgery. It takes approximately one year for full recovery.

Outcomes

Current data show that patients who undergo TAR have improved patient-reported outcomes and decreased pain after surgery and achieve a 30- to 40-degree arc of motion, on average. Similar to data on total knee replacement, patients with more severe radiographic arthritis and worse function preoperatively have greater improvement after TAR compared to patients with less severe arthritis and better baseline function.

When comparing TAR to ankle arthrodesis, data are mixed. Most studies report that patients undergoing TAR have slightly better patient-reported outcomes and a better gait but a higher risk of reoperation compared to patients having ankle arthrodesis. However, there are studies that have shown no difference between the two surgical options.

In my practice, I typically perform TAR unless there is a contraindication or the patient prefers ankle arthrodesis. For patients with a significant deformity of the ankle or foot, I often perform two-stage surgery. The first stage is deformity correction followed three to four months later by TAR.

In conclusion, TAR is a viable and successful option for patients with end-stage ankle arthritis. Though there are contraindications, most patients are candidates.Surgeons should discuss the risks and benefits of both TAR and ankle arthrodesis with patients who are candidates for TAR.

Dr. Miniaci-Coxhead is an orthopaedic surgeon in the Foot & Ankle Center at Cleveland Clinic, with a joint appointment in Cleveland Clinic Sports Medicine Center.