Ankle arthroplasty can relieve pain and maintain motion in an arthritic ankle joint. The procedure is an alternative to ankle fusion which also can relieve pain but eliminates motion in the joint. New surgical techniques and advancements in orthopaedic technology are redefining ankle arthroplasty, including the development of an innovative total ankle prosthesis which has helped to boost the resurgence of these replacement surgeries over the past decade.
John Kirchner, MD, of Southlake Orthopaedics in Hoover has been doing total ankle replacements for about 11 years. The number of procedures has increased to about four or five each month, and he has about 300 active implants. Kirchner says the number one reason for ankle replacement surgery is arthritis resulting from a traumatic injury that leads to a loss of cartilage.
"When a person moves at a slight jog or a fast walk, the ankle joint has six times the amount of body weight force going through it. That's a lot of stress in a small surface area," he says. "Most people and a lot of physicians are still are not aware that ankle arthroplasty is an option for arthritic ankles. An increasing amount of literature has documented proof that it is an excellent alternative to ankle fusion in the correct patient."
Kirchner's surgical team uses the Salto Talaris® total ankle prosthesis. Modeled after the human anatomy, it provides surgeons the ability to reproduce the natural flexion and extension axis of the ankle. Maintaining the natural motion of the ankle may reduce the stress on the medial deltoid ligament complex while allowing the replaced ankle to mimic the same motion as the opposite healthy ankle. "That will allow for a more natural gait for the patient post operatively," he says.
Another reason for success with this ankle arthroplasty procedure is the difference in how the bone is contoured during surgery. "Instead of doing a large block cut, we contour the bone with multiple small cuts, similar to setting a diamond. That allows the implant to resurface the rounded talar dome," Kirchner says. "While all implants have polyethylene bushings, the talar component of the Salto Talaris is cobalt chrome, and the tibial base is titanium. With those three components, the implant requires much less joint resection than older model implants. The Salto Talaris requires less joint bony resection which leaves more of the patient's own bone available in case a revision is necessary."
Close up of the prosthesis
The standard recommendations for ankle arthroplasty surgical candidates suggest someone age 50 or older with a normal body mass index. The candidate must not be diabetic and cannot have an open injury with infection. "The surgery is good for people for whom we can preserve a mobile segment so they aren't putting stress on their knees, lower back or remaining ankle joints," Kirchner says. "A successful replacement gives the patient better movement and a better lifestyle."
Nannie Fox of Luverne, Alabama, is looking forward to better mobility following her recent ankle arthroplasty surgery at Southlake Orthopaedics. Kirchner performed the surgery at the end of June, and Fox is biding her time while her ankle heals enough to begin physical therapy.
Fox's ankle problems began when she was a majorette in college. "I stepped in a hole while I was marching and broke my ankle. Years later, I fell at church and broke my leg and the same ankle. I've had trouble ever since," she says. "It never healed correctly which has caused pain in my hip and knee on that side. I've had two knee replacements, and the right knee was sore."
A surgeon in Montgomery suggested an ankle fusion, but she kept searching for other options. She found information about ankle arthroplasty and thought that procedure could offer a better outcome in most cases with the same amount of recovery time and physical therapy. "I cancelled my fusion surgery and found Dr. Kirchner online. I made an appointment, and here I am. He and his staff were great, and I have been pleased with my care."
Fox will be in a wheelchair for another four weeks, but she is optimistic about her outcome. "I hope I can be normal again," she says, "and I will do the necessary physical therapy to get there."