The Herald Bulletin

June 18, 2013

Joint effort

Local surgeon helps make better ankle replacement

By Baylee Pulliam The Herald Bulletin
The Herald Bulletin

---- — ANDERSON — A few months ago, Gary Coon couldn’t walk.

The arthritis in his ankles was debilitating — keeping him from his favorite hobbies, such as fishing or golf.

But earlier this year, Coon regained his mobility. He’s a ‘bionic man,’ after having his right ankle replaced with a metal and plastic one co-designed by Dr. Steven Herbst, a Central Indiana Orthopedics surgeon, who also works with Community Hospital Anderson.

“It feels pretty good, so far,” Coon said.

The total-ankle replacement, produced by musculoskeletal health care company Zimmer in Warsaw, is the culmination of 11 years of planning, and a collaboration between doctors and engineers around the country. The product itself is simple and trim — a piece of cartalidge-simulating plastic, sandwiched between two pieces of fibrous metal.

“My kids say, ‘you spent that many years on that, and it doesn’t even light up or anything,’” Herbst said.

While the replacement doesn’t glow, play MP3s or have WiFi connectivity, it does seem to offer patients some pretty stellar results, he said. Since its launch six months ago, about 70 have been used around the country. In Indiana, Herbst has surgically implanted 10, all at Community Hospital Anderson, with no major complications and “very happy patients” so far.

According to Community President Beth Tharp, the new technology jibes well with the hospital’s philosophy of improving services and technology. “It’s exciting to have someone on our medical staff who is involved in the process of creating this new technology for patients,” she said.

Herbst’s product is different from previous options for osteo-, post-traumatic and inflammatory arthritis sufferers, who might need ankle surgery.

There was the gold standard — fusing bone in the upper foot to those in the leg, completely immobilizing the joint. Since most orthopedic prosthetic design breakthroughs were for the hip or knee, ankle implant options were scant, and “for a long time have only seen fair results.”

“Before, they didn’t really have another choice,” he said. “Things are less figured-out, in the foot and ankle world.”

Herbst offers his patients both options, but many have chosen the new replacement. One reason is that it typically lasts between 10 and 20 years — much higher than the eight- to 10-year average for most other replacements. Herbst’s implant uses a special kind of plastic that’s more durable, he said.

There are a few other differences, including improved bonding with the bone. Zimmer’s Trabecular metal is porous, making it more conducive to bone in-growth.

It’s also placed from the side, where others are placed from the front, which, among other things, makes scarring less noticeable. Herbst said the tibia bone in the calf is broken on the way in, and repaired on the way out.

“There’s less bone loss, from a volume standpoint,” he said, adding “it really looks like a normal ankle. It mimics natural foot geometry.”

There are some conditions that would preclude the use of an implant, he said. For example, they don’t jibe with some deformities, if the patient has a history of infection or certain diabetic conditions, which could lead to problems or the replacement loosening.

But things are going fine for most patients, such as Coon, who’s considering having his other ankle replaced, too.

“Might as well,” he said. “The other one feels pretty good.”

Like Baylee Pulliam on Facebook and follow her @BayleeNPulliam on Twitter or call 648-4250.