Michael Suter feared a long recovery when his doctor told him he needed to have both knees replaced.
The 56-year-old Sandy Spring resident knew the surgery was inevitable. He had endured significant knee pain for years, a condition brought on by arthritis.
Then he recalled that one his wife’s friends had undergone a similar procedure and had been walking with a cane two weeks later.
So Mr. Suter did some research and learned about a recent surgical innovation promising quicker healing time for people with his condition.
Doctors are turning to minimally invasive knee-replacement surgery as an alternative to traditional replacement techniques. The process requires more time in the operating room, but the surgery involves cutting less muscle and lets patients rehabilitate the knee sooner than with current methods.
The procedure hasn’t existed long enough for a full body of research to develop, however, so some physicians prefer the existing techniques, which they say are time-tested and provide exemplary long-term results.
Dr. Anthony Unger, an orthopedic surgeon and director of George Washington University’s program for minimally invasive joint-replacement surgery, says the impetus for the new procedure came from patients.
“They didn’t want to stay in the hospital for a long time,” Dr. Unger says. “It doesn’t add any long-term longevity or durability … but it’s a less-frightening operation.”
The learning curve for doctors who don’t perform the operation is, alas, a bit steep.
“You don’t instantly grasp it. You have to work with other surgeons,” he says, and newbies must learn to control new equipment, including computer guidance systems that help with the small incisions.
The procedure isn’t for every patient. Those who are overweight or have had previous knee surgeries aren’t candidates. Neither are patients with deformed knees or who are in poor health.
The surgery is recommended for patients who are small — so the implant can be small and easier to manipulate — with fairly good range of motion. Patients must participate in physiotherapy before surgery, and the procedure requires a rapid and vigorous rehabilitation plan — including stretching and range-of-motion exercises to enhance flexibility and strength. Patients generally complete the rehabilitation in six weeks, compared with the traditional 12 weeks.
There’s certainly a need for knee replacements. In 2004, 478,000 people underwent total knee-replacement procedures in the United States, up from 418,000 the previous year, according to a the National Hospital Discharge Survey.
In knee-replacement surgery, doctors remove damaged bone and cartilage from the shinbone, thighbone and kneecap and implant an artificial joint made of ceramic, polymer and metal alloys to refashion the joint. The newer materials used in modern surgeries mean patients can hope to have a functional knee for up to 20 years, if not longer.
Dr. Wiemi Douoguih, director of sports medicine in Washington Hospital Center’s department of orthopedics, says the minimally invasive surgery could become the standard way of replacing worn-out knees.
For now, “the verdict is still out,” Dr. Douoguih says. “It’s too early to tell. … We have to be careful to make sure it has the same benefits [as the existing methods] over the long term.”
He also advises caution because the longer time required to complete procedures such as minimally invasive knee surgery leaves patients open to a greater possibility of infection.
Count Dr. Jay Mabrey, chief of orthopedics at Baylor University Medical Center in Dallas, among those who want more information about the procedure.
“The data that’s out there doesn’t seem to point toward minimally invasive surgery as having a great advantage over standard surgery,” Dr. Mabrey says.
One area in which the technique, along with minimally invasive hip surgeries, is paying dividends comes with pain-management methods.
“I’ve found by doing a less invasive knee surgery and applying modern pain-management protocols, the results are just as good as [for] those [doctors] doing the minimally invasive surgery,” Dr. Mabrey says. This hybrid approach marries the best elements of each procedure.
Dr. Mabrey gives patients a low dose of painkiller before surgery and uses nerve blocks to minimize discomfort.
“The patient never gets to ‘see’ the full dose of pain,” he says.
He also occasionally uses platelet-rich plasma, derived from the patient’s own blood, for such procedures.
“It reduces the amount of swelling and promotes healing,” he explains.
Minimally invasive surgeries can be credited for medical advances such as pain management and diminished surgical cuts, and even doctors who don’t completely go the minimally invasive route still adhere to some of its principles.
“The vast majority are using incisions that are smaller then they were 10 years ago,” Dr. Mabrey says.
Some knee-replacement surgeons also are turning their attention to the differences between male and female patients.
In May, George Washington Hospital began offering the new Zimmer Gender Solutions Knee for women with knee problems. The replacement knee has a thinner profile and a more contoured shape to approximate how a woman’s knee looks and moves.
George Washington Hospital’s Dr. Unger says no matter the patient’s sex, the number of knee-replacement surgeries is rising rapidly, especially given the population’s overall weight gain and an increase in sports injuries.
Mr. Suter, who had both knees replaced over the course of a week in March, is walking two miles a day.
“They want me to go three miles, but I get bored walking,” he says.
He’s not complaining; the extent of the discomfort he feels most mornings is a temporary touch of stiffness.
“The pain was nothing compared to what I thought it would be,” he says of the procedure.