Surgeon Uses Patient's Cells To Repair Knee

URL: http://www.abqjournal.com/health/160681health04-12-04.htm

Monday, April 12, 2004
Surgeon Uses Patient's Cells To Repair Knee
By Jackie Jadrnak
Albuquerque Journal Staff Writer

Barbara Martinez can hardly wait until she gets back to playing catcher for a softball team that includes husband Arthur on the mound. Her orthopedic surgeon, Sam Tabet, manages not to wince at the thought of the pressure the deep crouch would put on her knee, but says, "I would recommend to her to be an outfielder."

Well, they don't have to come to an agreement right away. It will take up to a year for Martinez to fully recover from surgery to rebuild cartilage that has worn away on her knee. The procedure she had uses cells grown from the patient's own cartilage. The technique is not terribly new or rare, but still is expensive enough to be considered a last resort, according to Tabet.

But it may be the wave of the future.

"This is the future we were told we were going to see," said Frosty Mayfield, a physician assistant who works with Tabet. The next step, if researchers can find the right answers, might involve simply injecting the cells directly into the knee.

As it is, Martinez and others like her have to put up with surgery that opens up the knee.

But first, let's start with the problem.

Martinez developed a worn-out spot in the cartilage at the end of her thigh bone where it meets the shin bone. She said she has had knee problems for a long time, starting back in 1992. That's when she felt a tug in her knee as she turned while lifting frozen bread dough in her bakery job, she said. She reinjured it in '95 or '96, she said. Most recently, she was faced by the pain of a worn-down spot that put more pressure directly on her bone and left inadequate surface for the joint to slide smoothly.

"What I want out of this (operation) is just for her to live with no pain," husband Arthur Martinez said.

Besides coming back to softball, Martinez has seven grandchildren she needs to keep up with, said Tina Torrez, Martinez's daughter and mother of three of the grandkids.

To get herself back to active status, Martinez opted for the autologous chondrocyte implantation?- the cartilage reconstruction using her own cells. That approach isn't for everyone, Tabet said. It isn't used on people with osteoarthritis whose cartilage is so worn down that bone is rubbing on bone. Those folks often end up as candidates for knee replacement.

Others with very small, worn-down areas may try a simple washing of the joint and/or scraping and drilling techniques that penetrate the main part of the bone. That intentional injury to the bone releases blood that helps spur cartilage growth. However, that cartilage is more scarlike and doesn't hold up well under the normal stresses on that part of the knee, Tabet said.

For older people, especially those who aren't very active, that procedure's benefits may last long enough. That surgery is arthroscopic, using only small incisions, and can cost as little as $6,000, he said. In comparison, the cost of growing a patient's own cartilage cells alone is about $14,000, he said. The total package, with surgical and hospital costs, runs about $23,000.

Studies that have followed these patients for up to nine years, though, show very little deterioration in the new cartilage, Tabet said. At the same time, the procedure isn't foolproof. Eighty percent to 85 percent of the patients have good to excellent results, he said. But that means 15 percent to 20 percent aren't successful and may need follow-up surgery, he added.

Martinez was hopeful going into her procedure. "I'm excited, because I have so many people praying," she said. "I have a lot of faith. The Lord is my healer."

The surgery was straightforward, if painstaking. Tabet sliced open her knee, with her leg bent to expose the joint surface on the thigh bone. He scraped down the worn area, evening it out with a border of cartilage around it. With that work done, he moved down the leg, opening an area over the shin bone. There he marked off an area about the size of the worn spot and scraped off a thin layer of the outer bone?- the blood-rich periosteum. The resulting patch was transferred back to the worn spot, where Tabet stitched the patch onto the cartilage border, then tacked it down even more with glue around the edges. Then came the vials of cartilage cells grown from a chunk of cartilage taken from Martinez in a surgery a few weeks earlier. Tabet filled a syringe from the vials and injected the liquid into the blisterlike patch he had built on her damaged joint. After he plugged the hole from the injection with more glue, it was simply a matter of stitching up both incisions.

If all goes well from there, the cells would start growing a layer of cartilage over the worn-down spot. For the first few weeks, Martinez will have to spend several hours on a machine that bends and unbends her leg for her. She could expect to spend six weeks on crutches, Tabet said, and a series of exercises will be prescribed throughout her recovery period. Full rehabilitation takes about a year, but she probably can return to work in 12 to 16 weeks, he said.

Now managing a charter school's cafeteria, Martinez said she's eager to return to work. "I like my job," she said. In the meantime, the grandkids, aged 5 to 16, are expected to pitch in and help out during her recovery. "They'll spoil me," Martinez said with a smile.