New Knees, No Big Deal

Minimally invasive surgery uses smaller incisions, spares muscles and tendons, requires less medication, and gets patients up and out fast

Cliff McCrath's knees were shot. After 44 years of coaching college soccer -- and years of wearing cleats himself before that -- the 68-year-old jokes that his legs had become so bowed, someone could have tossed a medicine ball between his knees and it wouldn't brush his pants. So, like hundreds of thousands of Americans every year, McCrath had his knees replaced, in mid-February.

Unlike most of the others, however, McCrath says he was "up and at 'em and feeling great from the first day." He was back home in four days and walking entirely without crutches four days after that. Today he no longer needs to sit as he coaches the men's soccer team at Seattle Pacific University, and for the first time in years he works out on a treadmill.

The difference? McCrath underwent the latest thing in joint replacement: minimally invasive surgery. Borrowing from such less traumatic procedures as arthroscopy and endoscopic abdominal surgery, doctors are replacing knees and hips through much smaller incisions. They're also finding ways to avoid slicing through muscles and tendons and, guided by computers, they're installing artificial joints more accurately. The result: less injury and pain and speedier recoveries.

Although increasingly common and successful, conventional knee-replacement surgery continues to be a dreaded operation. Following the standard procedure, which starts with an incision up to 12 inches long, patients often spend their first post-op day or two doped up in a hospital bed. Once they're out of bed, they need a walker or crutches to move around and they remain hospitalized for a week, on average. Then it's two or three months of physical therapy, pain medication, and relying on a cane.

With minimally invasive surgery, the cut is three-to-six inches long. Doctors work through this smaller opening to remove the ends of the femur and tibia and replace them with an artificial joint. Patients often can bend their knees nearly at a right angle later the same day and take steps the next day with only a cane. They spend three or four days in the hospital and are walking without any assistance in a few weeks. "To me, there was nothing to it," says Roy Gould, 62, a retired school-bus contractor who had both knees replaced last February and was home three days later.

The biggest challenge is finding an experienced practitioner. Only a fraction of the nation's 20,000 orthopedic surgeons perform the procedure, so just 20% of hip and knee replacements are minimally invasive, estimates Steven Hirsch, general manager of the reconstructive division of Smith & Nephew, an artificial joint maker.


But more doctors are learning the ropes. DePuy Orthopaedics, a subsidiary of Johnson & Johnson (JNJ ), is putting 75 surgeons a month through a two-day, hands-on course in the technique. Booked solid through the end of the year, DePuy may add a second session per month. Smith & Nephew and Zimmer Holdings (ZMH ), another artificial joint manufacturer, are training similar numbers of doctors in the new method. In three or four years, Hirsch predicts, this gentler form of joint replacement will become the standard. We may even start to see minimally invasive spinal operations.

Medical-products companies have modified their implants and downsized their surgical tools to allow doctors to work through smaller wounds. DePuy has developed software that enables surgeons to look at a computer screen and "see" under a patient's skin, based on CAT scans of the bones taken before surgery and the position of two light-emitting diodes that are pinned to the leg.

Doctors are discovering new ways to minimize incisions, too. Like plastic surgeons, many orthopedic surgeons now stretch a patient's skin and adjust the joint during surgery to expose different areas underneath, eliminating the need for longer cuts. And many surgeons no longer slice through leg muscles, such as the quadriceps or tendons, as they remove bones and insert the implant. Instead, they make only a small cut along the grain of the muscle or spare the muscle altogether by working beneath it. That means faster recoveries and less pain.

Perhaps no doctors have embraced this approach as fully as Richard Berger and Aaron Rosenberg at Rush University Medical Center in Chicago. In 2002, the duo started replacing hips and knees as outpatient surgery. Operations are done around 7 a.m. and patients go home roughly 12 hours later. The doctors also do not use general anesthesia. Instead, patients are sedated with Valium and numbed from the waist down with a spinal painkiller. Some are even alert and talking during surgery. As a rule, surgeons require patients to be hospitalized for at least a couple of days in case of complications. But Berger and Rosenberg say they've done hundreds of joint replacements with same-day discharges and have never had a readmission.

Minimally invasive surgery is not an option for people who are grossly overweight, have joints that were badly damaged in an accident, or have already had major joint operations. Physicians say there are no added risks, and researchers are collecting data that show how beneficial the new technique can be for everyone else. Dr. Richard Laskin, a hip-and-knee replacement specialist at New York's Hospital for Special Surgery, says patients who have minimally invasive surgery take 35% to 40% less pain medication than those who have the standard operation, according to a study he recently oversaw.

Sue Centko, 51, a postmaster in Pana, Ill., is one such patient. She had arthroscopy on her knees twice and was on crutches for five weeks each time. Then she had minimally invasive knee replacements -- and was walking without crutches or a cane two weeks after the second operation. Before, she was on pain pills. But now, even while lifting 70-pound packages at work, she needs no medication. "I saved a month's worth of pain and recuperation," she says. Who wouldn't jump at that?

By Michael Arndt

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