A TRIBUNE EXCLUSIVE REPORT /HEALTH CARE IN SLO COUNTY

"Amazing, huh?" asked Teri Davis.

The Atascadero bartender was padding down the hall at French Hospital Medical Center just a day after a doctor sawed out her right knee joint and replaced it with a fake one.

"Everyone who wants a knee done is jealous of me," she said. "They're all saying, 'Wow, I want that.' "

The next morning, she walked out the hospital doors and headed home.

Davis and her quick recovery are emblematic of a trend among Central Coast orthopedic surgeons, many of whom are using new techniques and technologies to get their patients home quicker or leave them with longer-lasting joints.

San Luis Obispo County is a good place for that. About 400 patients a year undergo a knee replacement locally, according to a Tribune analysis of 2003 state data. That means local doctors install more than one fake knee each day.

They'll probably do more in the future. According to the UC Santa Barbara Economic Outlook, the number of county residents between the ages of 45 and 60 increased by 73 percent over the last decade. That number is expected to jump dramatically when baby boomers start retiring around 2010.

To cope with such a population, several new technologies have emerged on the Central Coast.

Arroyo Grande Community Hospital is one of three in the nation to use a machine called PiGalileo, which uses a computer to help position knee implants accurately on the bones.

Sierra Vista Regional Medical Center is considering starting a knee replacement program in its operating room within the next few years, while Davis' doctor, Dan Woods, has teamed with French Hospital Medical Center to promote a knee replacement technique that uses far smaller incisions.

"Knee replacements and hip replacements are two of the most successful operations we have," said Arroyo Grande orthopedist Tom Ferro. "They're coming of age in this area."

If Teri Davis had her knee replaced 15 years ago, she would have been hospitalized for a week and would have endured three months of rehabilitiation. But with this latest surgery, she's headed for a vacation to Hawaii after four weeks of recovery.

Davis' surgery

Davis is in her 40s, but her doctor, Dan Woods, says she had a 60-year-old's knee from hours spent standing and tending bar.

The 10 years of mud wrestling in Hollywood didn't help, either.

"That was a dirty job," she said from her hospital bed two weeks ago, "but somebody had to do it."

Shuffling into her Atascadero home after work, Davis noted she would invariably head to the freezer for ice. The pain was bad, she said, and she became depressed.

The single mother was also having trouble finding a physician who would accept her MediCal insurance -- which is not an uncommon problem in the county because of the program's low reimbursement rates.

Then she received a referral to Woods, who performed in late May what's known as minimally invasive surgery.

That technique aims to make smaller incisions and cause less muscle damage, which can lead to quicker healing.

Other orthopedists in the area perform similar surgeries, but not necessarily with the same equipment.

Woods began by making a four-inch-long cut along the side of the knee, as opposed to the foot-long incisions of the past.

He followed with a second cut along a fleshy capsule that holds the kneecap in place, and, after carefully separating the inside layers of the knee, he pushed the kneecap off to the side. This exposed the joint.

Typical operations require longer incisions, which let surgeons flip the kneecap over, completely out of the way.

Doing so lets doctors see more of the inside of the knee, but it also causes a prolonged, more painful recovery because it usually requires a slice along the thigh muscle.

Woods avoided that step with a collection of angled tools that gave him access to the joint through a smaller hole.

"It's more of a struggle to do everything this way instead of laying it all out, but it's worth it," Woods said.

After opening the joint up, he installed cutting jigs on the top of the shin and bottom of the thigh bone. Those jigs are small metal cubes that allowed Woods to saw the bone tips into shapes that fit perfectly into the prosthetics -- like a key and lock.

The doctor then glued in the prosthetics, which are identical to those used for typical replacements.

After inserting a slab of high-grade plastic between the shin and thigh bones to act as a bearing surface, the doctor sewed everything together.

It took about half an hour longer than a typical knee surgery, but Davis was walking the next day.

Other options

Davis -- young and fit -- was well-suited for her minimally invasive surgery, but that's not the case for all patients.

According to Michael Laird, another county orthopedist, physicians have a hard time doing the surgery on people who are morbidly obese, who have joint deformities or who are overly muscled.

It's also unclear how the surgery helps in long-term outcomes, he said, because there's not enough data yet. But it does seem to speed the recovery process and it leaves a less unsightly scar.

"There's real promise in trying to minimize the approach, but that's what we all tend to do in the right patient with the right procedure," he said.

For patients for whom minimally invasive surgery might not work and who are looking for a different approach, there's also a computer guided technique offered by Arroyo Grande surgeon Tom Ferro. His machine is one of three in the country made by Plus Orthopedics, but other companies such as Smith & Nephew Orthopaedics offer similar technologies.

Ferro's technique uses computers to help ensure that the prosthetic joint is properly aligned during surgery. If the cuts on the bones are just the slightest bit off-center and the prosthetic is put in sideways, the knee can abnormally wear.

That means the replacement will not last as long and could require a second surgery, called a revision.

"You need to be within 3 degrees of a mechanical axis," Ferro said. "Normal standard open total knees get there 70 to 90 percent of the time, and the Galileo gets there 99 percent of the time."

There has not been a tremendous body of research published on either type of knee surgery, but proponents say both work well.

In the future, Woods said he expects knee replacements to become even easier on patients. Doctors will continue to strive for smaller incisions when appropriate, and the prosthetics that they install may shrink further.

He also said prevention, through the use of medicines and lifestyle changes, will become the future focus.

It's unclear how well such measures would have helped Davis, since her injuries were related to direct trauma. But they would surely keep doctors nationwide from operating on many of the 365,000 knees they replace each year -- which would in turn reduce the cost burden on the health-care network nationwide.