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Dr. Knox Now Performing Uni-Knee Replacements

Some arthritis patients in the Twin Lakes area may not need to undergo total knee replacement surgery in the future. Dr. Thomas E. Knox is now also performing replacement of just the diseased part of the knee joint. This surgery is called unicondylar arthroplasty, or replacing one side of the knee.

Dr. Knox estimates about 20 to 25 percent of the patients who require knee surgery could be helped with this procedure. Patients whose knee damage from osteoarthritis is confined to one side of the knee could benefit, no matter what the age of the patient, young or old. "The number of persons undergoing unicondylar surgery is already growing because it is best for the patient with a true unicompartmental knee problem," the surgeon stated. The American Academy of Orthopaedic Surgeons estimates that about one-quarter of a million persons have knee replacement surgery annually, and about 5,000 have the uni-knee surgery.

The patient benefits because unicondylar arthroplasty is a minimally invasive solution with a two to three-inch incision instead of the eight to 12-inch incision that is common for total knee replacements. The hospital stay may be shorter, and recovery time may also be less, often two to five weeks in contrast to a maximum of six months for total knee replacement surgery. Dr. Knox said unicondylar arthroplasty "preserves bone rather than sacrifices bone."

One of the procedure’s most important advantages, Dr. Knox said, is 20 to 30 percent more range of motion after uni-knee surgery compared to total knee replacement. Of course, as in all joint surgeries, a successful recovery depends upon a number of factors, including the patient’s activity level, weight, bone quality and commitment to rehabilitation, Dr. Knox said.

Growing support of unicondylar surgery results from improvements in the design of the prosthesis used, Dr. Knox said, improvements in surgical instrumentation now available, and long-term success of the procedure comparable to total knee replacements. The implant replaces only the worn surface of the bone, preserving the remaining bone and ligaments. Even if the joint’s degeneration continues in the arthritic knee, the implant will not hasten the process, Dr. Knox said.

A number of companies manufacture high-quality unicompartmental prostheses and offer training for their implantation, Dr. Knox said. He uses Biomet prostheses, which have a proven 10-year, 90 percent success rate, recently published studies show, he said.

Dr. Knox urges individuals suffering from knee pain to seek an early diagnosis. "Pain should be investigated by your physician, then the patient can weigh the treatment options available."

About 21 million people in the United States suffer from osteoarthritis, a result of excessive wear on joints or an injury during youth. It damages the cartilage that lines the joint and results in pain, swelling, creaking, and stiffness in the affected joint.

Dr. Knox practices at Regional Orthopaedic Health Care, #3 Medical Plaza in Mountain Home, telephone (870) 424-3400 or 1-800-621-3218 in Arkansas and Missouri. Regional Orthopaedic Health Care provides bone and joint disease evaluation, treatment and surgery, arthroscopic joint surgery, open and endoscopic carpel tunnel release, sports medicine, laser surgery, hand and shoulder therapy, in-office nerve conduction studies, evaluation of hand and wrist injuries, isokinetic exercise equipment and industrial orthopaedics