Dr.Thomas E. Knox received recognition in the local newspaper's Health & Fitness pages on March 6, 2001, for being the first physician in Arkansas to use a new type of knee implant in knee replacement surgery. Two separate news articles were written by Sharon Miller of the staff of The Baxter Bulletin, Mountain Home, Arkansas. One is about the man who received the first of the new implants, and the other focuses on the implant itself and its development.

New Knee Implant Material Makes State Debut in MH

A quarry accident that smashed Roy Eddings' knees 40 years ago also dashed his chances for a pain-free life. But, he's hoping a new type of knee implant will end or at least reduce the pain he has endured since the accident.

The first oxidized zirconium implant to be used in the state was placed in Eddings' knee at Baxter Regional Medical Center Feb. 21 by Dr. Tom Knox. After he recovers from the right knee total arthroplasty, Eddings said he plans to have the other knee repaired.

Eddings, now 60, is from St. Joe, about 15 miles north of Marshall. He came to Mountain Home for his surgery because of his confidence in Knox, he said.

Although the new implant material was not introduced to the American Academy of Orthopaedic Surgeons until last week, Knox, through association with the company that developed it, was on an early release list for the product. He was one of only two surgeons in the state authorized to use this prosthesis.

Knox said the oxidized zirconium is supposed to provide longer wear with less abrasion than materials used in the past.

Eddings' reaction to being the first in the state to receive this type of implant? "I don't care if I'm the first one or the last one as long as it will give me some relief," he said.

He described how he has spent much of the past 40 years in pain. "You wouldn't think knees would hurt that bad," he said.

When he was about 20, he was working for a quarry in Fayetteville hauling rock from the quarry to the crusher. "I hit a bluff head-on with 24 tons on back," Eddings said.

His knees were crushed against the dashboard.

In spite of past surgeries to repair his knees, and laser surgery to clean them out, the pain has remained.

By the time he went in for surgery Feb. 21, he was hardly able to function. He would sleep in a recliner, the only place he could get comfortable. He was having to walk on crutches.

After his surgery, there was soreness from the procedure, but no more pain than he had before the surgery, Eddings said. Within a few days of the surgery, he said, there was less stiffness than before.

He will continue rehabilitation at BRMC but was to have gone home at the end of last week. Eddings said he is looking forward to being able to hunt and fish without the knee pain that has interfered with his enjoyment of the outdoor activities.

Knox was assisted in the operation by BRMC staff members Sherry Evans, RN, Michelle Bird, CST, Daniel Berry, ST, and Bill Moore, ST.

Doctor First to Use New Implant

A new type of knee implant made its Arkansas debut in Mountain Home Feb. 21. The replacement surgery was done by Dr. Tom Knox.

The oxidized zirconium implant was introduced at the American Academy of Orthopaedic Surgeons at its annual meeting in San Francisco Feb. 28 to March 4. Knox had been invited to help with the presentation, but his busy schedule prevented his making the trip.

Knox was on an early release list to have access to the new implants through an association with Smith and Nephew Orthopaedics, the company that developed the implant.

He said the material has been used successfully in hip replacements, but an entirely different design was required for knee implants.

While older types of implants would last eight to 10 years, Knox said, hopes are the oxidized zirconium will last 14 years or more. Another advantage, he said, is there is less abrasion with the new material.

"Oxidized zirconium addresses one of the most critical issues in clinical orthopaedics today, which is the generation of wear debris," said Leo Whiteside, M.D. of the Missouri Bone and Joint Center in St. Louis. "And the bottom line is the lower the amount of wear debris generated, the longer the implant will last."

According to information from Smith and Nephew, orthopaedic surgeons have traditionally delayed joint replacement surgery in patients younger than 65 because they did not expect the materials to withstand the wear placed on them for longer than 10 years or so.

It said that currently, most knee implants are made from a cobalt-chrome alloy that slides against a plastic (polyethylene) bearing. "The motion and friction caused by daily living can damage the implant's surface and cause metal and polyethylene wear debris, ultimately causing bone loss and the need for another implant," said a press release from the company.

"We've been evaluating the new knee in patients for the past two years, and we have been very pleased with the clinical outcomes of the oxidized zirconium technology," said Richard Laskin, M.D. of the Hospital for Special Surgery in New York. "The exciting part is that this is not an externally applied coating. The metal component is heated and infused with oxygen until the outer surface naturally turns into a ceramic."

Slade Goldstein, a 36 year-old former amateur athlete from Charlotte, N.C., received one of the first oxidized zirconium implants. His knees had degenerated after years of wrestling practice and competition. Goldstein said he is out playing golf and walking around now without the pain he had before surgery.

"We believe that this is going to be an industry-defining technology," said Smith and Nephew Orthopaedics President Larry Papasan. It's really a testament to what can happen when the industry listens to surgeons and seeks to find completely new and innovative solutions to their clinical issues."

More than 600,000 total knee replacements are performed each year worldwide. The annual total global knee market is estimated to be $2 billion. Anyone wanting more information about this new type of knee implant may visit www.oxidizedzirconium.com.