THERE is nothing like a new hip or knee to put the spring back in your step. Patients receiving joint implants often are able to resume many of the physical activities they love, even those as vigorous as tennis and hiking. No wonder, then, that joint replacement is growing in popularity.
In the United States in 2007, surgeons performed about 806,000 hip and knee implants (the joints most commonly replaced), double the number performed a decade earlier. Though these procedures have become routine, they are not fail-safe.
Implants must sometimes be replaced, said Dr. Henrik Malchau, an orthopedic surgeon at Massachusetts General Hospital in Boston. A study published in 2007 found that 7 percent of hips implanted in Medicare patients had to be replaced within seven and a half years.
The percentage may sound low, but the finding suggests that thousands of hip patients eventually require a second operation, said Dr. Malchau. Those patients must endure additional recoveries, often painful, and increased medical expenses.
The failure rate should be lower, many experts agree. Sweden, for instance, has a failure rate estimated to be a third of that in the United States.
Sweden also has a national joint replacement registry, a database of information from which surgeons can learn how and why certain procedures go awry. A registry also helps surgeons learn quickly whether a specific type of implant is particularly problematic. "Every country that has developed a registry has been able to reduce failure rates significantly," said Dr. Daniel Berry, chief of orthopedic surgery at the Mayo Clinic in Rochester, Minn.
A newly formed American Joint Replacement Registry will begin gathering data from hospitals in the next 12 to 18 months.
Meanwhile, if you are considering replacing a deteriorating knee or hip, here are some ways to raise the chances of success and avoid a second operation.
EXPERIENCE COUNTS Choose — or request a referral to — an experienced surgeon at a busy hospital. "The most important variable is the technical job done by the surgeon," said Dr. Donald C. Fithian, an orthopedic surgeon and the former director of Kaiser Permanente's joint replacement registry.
Ask for recommendations from friends who have had successful implants and from doctors you know and trust. When you meet with the surgeon, ask how many replacements he or she does each year.
VOLUME MATTERS A study published in The Journal of Bone and Joint Surgery in 2004 found that patients receiving knee replacements from doctors who performed more than 50 of the procedures a year had fewer complications than patients whose surgeons did 12 procedures or fewer a year.
The researchers documented a similar trend when it came to hospital volume. Patients at hospitals that performed more than 200 knee replacements a year fared better than patients at hospitals that performed 25 or fewer.
ADJUST EXPECTATIONS Not everyone with joint pain will benefit from a joint replacement.
An implant can help reduce pain and improve mobility if the joint surface is damaged by arthritis, for instance. But a new joint will not help pain caused by inflammation of the surrounding soft tissue, said Dr. Berry, who is also vice president of the board of the American Academy of Orthopaedic Surgeons.
Some people with mildly arthritic joints, for instance, can manage well with the judicious use of medication. "Surgery comes with complications and risks, and should not be approached lightly," Dr. Berry said.
Joint replacement is not a minor operation. If you have uncontrolled high blood pressure or another serious chronic condition, a joint operation may simply be too risky for you.
NARROW YOUR OPTIONS "There is no one best joint," Dr. Berry said. "A successful replacement depends on selecting the right implant for the patient."
A good surgeon will recommend an implant that makes sense for your age, activity level and the shape of your joint. Younger or very active people who place more physical demands on the implant, for instance, may benefit from newer hard-on-hard bearing surfaces, like those made of ceramic, said Dr. Joshua J. Jacobs, chair of orthopedic surgery at Rush University Medical Center in Chicago.
In general, be wary of the latest, most advanced new joint. There is little evidence to support the use of more expensive designs over basic ones, said Dr. Tony Rankin, a clinical professor of orthopedic surgery at Howard University. One recent study found that premium implants fared about as well as standard implants over a seven- to eight-year period.
Be skeptical, too, of advertising gimmicks. "I had a 78-year-old patient with a perfectly good knee replacement come in and ask if she should have gotten the 'gender knee,' which she had seen advertised on TV," Dr. Rankin recalled. "She was doing well, but was swayed by the idea of a knee made just for women."
GATHER THE DATA Once you have a recommendation or two from a surgeon, find out how well the joint has performed in others and if there are known complications. The newer metal-on-metal hip implants, for instance, are somewhat controversial and may cause tissue and bone damage in certain patients.
Ask if the hospital has a registry that tracks joint replacements. If so, ask to see the data on the implants you are considering.
It is also helpful to understand what the operation involves, including the materials that will be used and how the surgeon plans to fix the joint to the bone. You can learn more about your operation at the American Academy of Orthopaedic Surgeon's patient information Web site, orthoinfo.org.
If you want to delve deeper, look at a large national registry from another country, like Australia (which can be found at dmac.adelaide.edu.au/aoanjrr/publications.jsp). The annual report of Australia's registry lists knee and hip implants that had a "higher than anticipated revision rate."
A caveat: the information can be difficult to parse for a layperson. "A surgeon can provide perspective on information that, taken out of context, could be misleading," Dr. Rankin said. So discuss it with your surgeon.
PLAN YOUR RECOVERY To avoid complications during your final stage of recuperation, discuss with your doctor in advance the support you will need when you return home, Dr. Berry advised.
Recovery takes a different course for each patient, depending on the type of procedure and implant. In general, expect mild to moderate pain for the first few weeks. Some patients are able to return to work in one to two weeks, but full recovery can take six to 12 months, Dr. Jacobs said.
Make sure you have the help you need in the initial stages of recuperation. Since you may have difficulty getting around and won't be able to drive right away, you may want to have a friend or family member stay with you. You may even need to hire an aide or visiting nurse.
Follow your doctor's orders, and don't rush your recovery. You don't want your new joint to fail because you couldn't resist carrying loads of laundry up and down stairs, or felt compelled to rearrange the patio furniture.
If the new joint is given time to heal, you will find plenty of opportunities for all that in the future.