Don’t Be So Fast to Knock Knee Surgery

When a recent study found that a popular knee operation was only as good as a placebo for arthritis, some sufferers misconstrued the results, assuming that no surgery would help them.

Doctors are now trying to reassure people this isn’t the case.

The research, published two weeks ago in the New England Journal of Medicine, found that arthroscopic knee surgery, in which a surgeon inserts small instruments into the knee to explore the damage and make repairs, provided only mild relief at most for arthritis sufferers. Patients undergoing the surgery, the study said, had the same degree of pain relief as those who had a simulated procedure, in which tiny incisions were made and nothing more was done. Two years later, about 35% of study subjects thought they had improved; 65% either felt worse or stayed the same.

“Patients that have arthritis read this as saying any knee surgery for arthritis doesn’t work,” said Dr. Larry Dorr, director of the Arthritis Institute at Centinela Hospital in Los Angeles.

Arthroscopy remains a good operation for those who have suffered knee trauma and acute injury, such as an athlete with torn cartilage or a weekend athlete who tears a meniscus or ligament, he said.

For those with painful, stiff, arthritic knees who can’t get relief any other way, there are procedures to help.

“Total knee replacement is a highly successful operation and it’s shown to be one of the most effective treatments in terms of returning people to productivity.” Although knee replacements are painful and rehabilitation can take up to a year, he said, “as with most things in life, God gives you something when he takes something away. They last better” than less invasive operations.

Many doctors began offering the simpler arthroscopy, Dorr said, because patients were reluctant to endure the pain, cost and prolonged recuperation of knee replacement. But, he said, “there was no one overlooking it and saying, ‘This isn’t working and we should stop.’ ”

With arthritis, the procedure typically involves debridement, the sanding down of rough or damaged cartilage lining the knee, and lavage, which flushes cartilage fragments from lubricating joint fluid.

Up until the recent study, there hadn’t been scientific comparisons of arthritis patients who underwent the surgery with those who got a dummy procedure. Two years after the procedures, about 35% of all the subjects thought they had improved; 65% felt worse or stayed the same. However, the improvements were generally in perceived pain, not in any objective measure of whether they could function better, said Dr. Nelda P. Wray, the study’s senior scientist.

Of the 650,000 annual arthroscopies, orthopedic surgeons report doing 35% to 50% of them for the wear-and-tear of arthritis, Wray said. With 250,000 to 300,000 such procedures performed for arthritis each year at a cost of $5,000 each, more than $1 billion is being spent only to get a placebo effect, said Wray, a researcher and internist at the Houston VA Medical Center and Baylor College of Medicine in Houston.

“We probably should be taking all the time and resources and money that we use to do this and be applying them in better, more effective ways,” said Dr. Bruce Moseley, the Baylor orthopedic surgeon who performed the real and simulated surgeries for the study.

He and other orthopedic surgeons said patients have several options:

Nonsurgical management: Patients adapt their movements to what their knees will allow, while maintaining a healthy weight to alleviate extra stress on the joint. They can use pain relievers, such as acetominophen, or anti-inflammatories such as ibuprofen, the prescription COX-2 inhibitors like Celebrex and Vioxx, and cortisone injections.

Heat before activity and ice afterward can reduce pain and swelling. Physical therapy and massage can help. Exercise can strengthen the muscles around the joint, particularly the quadriceps at the front of the thigh and the hamstrings at the back of the thigh. The stronger the muscles, the more they can absorb the load placed on the joint.

Osteotomy: Popular before the advent of arthroscopies, it’s performed in a hospital on younger patients who want to reduce pain while preserving their knee joints. Because most people with arthritic knees become somewhat bow-legged or knock-kneed, doctors cut into either the leg bone, called the tibia, or thigh bone, called the femur, to realign the leg and knee and redistribute the load on the joint. Patients may return to work in three months; complete recuperation can take up to a year. About 4,000 are performed annually.

Knee replacement: The more common of two types is total knee replacement, in which surgeons replace worn or missing cartilage in all three knee compartments with a new lining consisting of metal on one side and plastic on the other. Recuperation can take six to 12 months.

Doctors performed 299,000 total knee replacements in 2000, according to the American Academy of Orthopedic Surgeons. A 1998 study in the British edition of the Journal of Bone and Joint Surgery found that after 10 years, 90% of these procedures are successful. When only a single knee compartment is affected, doctors may perform a unicompartmental knee replacement. Recuperation can take three to six months. About 30,000 are done annually.

Knee fusion: Also called arthrodesis, this rarely performed operation is sometimes recommended when a knee replacement may fail. It fuses the femur bone to the tibial bone, resulting in a completely stiff knee.

Discosupplementation: A relatively new therapy, involving injections of lubricant to replace knee fluid that has become less slippery because of arthritis. Although the injected hyaluronic acid eventually breaks down, some patients report years of relief, Moseley said.

Unispacer: The most recently developed knee procedure, it involves making a single incision and sliding a metal disk between the bones of the leg. Although FDA-approved, the procedure has been performed 900 times to date by the 350 orthopedic surgeons who have undergone training by the manufacturer. Said Dorr: “It may be the next easy solution for arthritis in the knee, like arthroscopy was, but there’s no good data yet that say it’s going to work.”

Looking ahead, Moseley said several treatments for a pre-arthritic condition called chondromalacia may turn out to be appropriate for osteoarthritis of the knee.

These include transplanting cartilage from one area of the knee to another, or in more complicated cases, harvesting a small amount of cartilage, sending it to a lab where it can be grown, and then re-implanting it into the knee.