Fremont doctor begins performing computer-assisted knee replacements

Keeping up with technology can help doctors stay at the top of their game.

That’s why Dr. Christopher Ihle studied to perform computer-assisted total knee replacements.

The orthopaedic surgeon from Heartland Orthopaedic has now performed about 15 of the computer-guided operations at Fremont Area Medical Center since starting the surgeries about three months ago.

“I became interested in the idea of computer-assisted about a year and a half ago,” Ihle said. “I kept an eye on it when it came out of the investigational stage.”

Before about a month’s worth of study and a three-day hands-on training course in Cincinnati with Johnson & Johnson-DePuy, he attended informational meetings about the new surgical procedure.

“At the initial stage, I was just trying to figure out if it was worthwhile — so many things in medicine are flash in the pan,” Ihle said. “One of the primary goals at Heartland Orthopaedic is to keep learning better ways to take care of patients. I think computer-guided surgery will help us make knee replacements last longer.”

He said the goal of the computer-assisted surgery is to help surgeons operate with smaller incisions and greater precision. It also helps surgeons to align the patient’s leg bones and knee implants with greater accuracy.

The computer uses cameras to take pictures of the knee and leg areas and software creates visual mapping for the surgeon to use. By taking the patient’s anatomy and translating it to the computer screen, the surgeon has an unobstructed view of the knee joint.

“We actually rebuild the patient’s knee in the computer,” Ihle said. “(The surgeon) and the computer make cuts on the computer before you cut the bone. It helps to balance out the cuts to maximize the motion of the joint.”

The objective of the system is to combine the accuracy of computer technology with the surgeon’s skill.

“With the computer, we can use less-invasive, more tissue-sparing techniques,” Ihle said. “The computer assists us with any angular problems.”

He said angular problems such as being bow-legged, knock-kneed or having suffered a previous fracture can all limit the life of a replacement knee joint.

In traditional knee replacement surgery, the surgeon makes an incision and inserts rods into the two leg bones to solve any angular problems.

“That gives us a very accurate knee,” Ihle said. “With conventional instruments, I’d say I’m within 2 to 3 degrees on all cuts. For me, my gut feeling is the more precise you can get, the better off.”

With the computer assisting him, the surgeon said he gets even more accurate knee replacements without having to implant metal rods into bones.

“With the computer, you don’t have to worry about the angle — you align the cutting device with the on-screen image,” Ihle said. “I’m still doing all the cuts, the computer is a guidance system.”

Image generation time before the operation adds about 20 minutes to the traditional 60- to 80-minute surgery.

“There are reports out now where (computer-assisted surgery) cuts down on post-op bleeding,” Ihle said. “With the more precise cuts we expect the knee replacements are going to last longer than the 15 to 20 years they do now.”

He said about 95 percent of replacement knees last at least 15 years. With the new computer-assisted surgery he hopes that same percentage will last at least 20 years.

Most patients who have total knee replacements are at least 55 years old or older.

“We keep trying to push for replacements that last longer and longer because patients are living longer and they’re active longer,” Ihle said.

Currently the computer-assisted surgery is only for a patient’s initial knee replacement and not subsequent replacements.

Unless requested, traditional surgery is performed more often — by about 3:1 — than computer-assisted and is not used on the majority of knees, Ihle said. While he has performed 15 computer-assisted total knee replacements in the past three months, Ihle has performed more than 1,000 traditional total knee replacements in the 15 years he has been in Fremont.

“I look at the knee involved and determine if the accuracy from conventional instruments is not going to be enough,” he said. “Some insurance companies are covering (the added cost of the computer and disposable parts) and some aren’t, but if I feel they need a computer-assisted surgery, I’ll go ahead and do it that way regardless of insurance.”

He said the added cost is about $1,000 per operation and FAMC is looking into purchasing one of the computers, which cost approximately $170,000. For now, Ihle has a computer shipped from Johnson & Johnson-DePuy in Cincinnati when he schedules operations.

“We’re real lucky that FAMC wants to stay on top of the latest technology,” Ihle said. “This is a very up-to-date hospital that really cares about the community.”