Knee and hip replacements are more likely to fail in smokers than nonsmokers

Knee and hip replacements are more likely to fail in smokers than nonsmokers, according to two new studies.

One study of 621 patients, including 131 smokers, who underwent total knee replacement found that the rate of knee-replacement failure was 10 times higher among smokers than nonsmokers -- 10 percent vs. 1 percent. Smokers also had a higher rate of medical complications than nonsmokers -- 21 percent vs. 12 percent. Complications included blood clots, anemia, heart problems and acute kidney failure.

The second study included hundreds of patients who underwent reconstruction of the acetabulum (the cup-shaped cavity at the base of the hip bone) with ultraporous metal, which is said to result in fewer failures than standard metal. The failure rate in smokers was 9.1 percent, compared to 3.4 percent in nonsmokers.

The studies were presented recently at the annual meeting of the American Academy of Orthopaedic Surgeons in San Francisco, which also included a forum on smoking and joint replacement.

At the forum, experts offered suggestions about how to get patients to quit smoking. One way is to refuse to perform surgery on patients who smoke, said Dr. Glenn Rechtine, an orthopedic surgeon and associate chief of staff and adjunct professor at the University of South Florida in Tampa. He said this rule has convinced 40 percent of his patients to stop smoking.

A three-step process has been effective for Dr. Richard Hurt, professor of medicine and director of the Nicotine Dependence Center at the Mayo Clinic in Rochester, Minn.

"First, ask about tobacco use," Hurt said in an academy news release. "Have your receptionist ask, your nurse ask, your physician's assistant ask, and you ask -- even if you already know the answer. Asking shows the patient that smoking is a serious problem that must be addressed. Then, advise the patient to stop smoking. Don't just say, 'you know, you ought to consider stopping someday.' Tell the patient, 'you need to stop smoking.'

Finally, because smokers are going to push back, it's important to offer help." Data and conclusions presented at medical meetings should be considered preliminary until published in a peer-reviewed medical journal.