Science / Medicine : Transplant: New Knee a Step Ahead

On Sept. 30, a transplant of an entire human knee was performed by Dr. Richard Schmidt, an orthopedic surgeon at the University of Pennsylvania Hospital in Philadelphia. This surgery, though still being evaluated, may offer new hope to patients with crippling injuries to their knees or serious diseases such as cancer.

Previously most such patients faced a series of limited choices: straight-bone replacements that meant walking with a stiff leg; customized, artificial knees that often loosened after several years, or amputation. Although it will be several years before the full results of the knee transplant are known, it is hoped that the replacement of one human knee with another will offer recipients extended use of a bending joint. Thus far the recipient in the Philadelphia surgery, Susan Lazarchick, a children’s counselor from Absecon, N.J., is doing well.

As with most experimental procedures, the September knee transplant was fraught with uncertainties and risk. Ultimately it became a test of ingenuity, skill and psychological durability on the part of the surgeon and the patient. The following account is Dr. Schmidt’s story of the surgery as told to Times staff writer Robert A. Jones.

I think I should start with a disclaimer. A knee transplant is a very serious procedure, and it’s not meant for everyone. The medical problem must be grave enough to justify the complicated surgery and the months of rehabilitation required. The process is so demanding that if I were faced with the choice of a knee transplant or a simpler procedure that would leave me with a stiff knee, I would take the stiff knee. A surgeon doesn’t need a knee that bends anyway.

When Susan Lazarchick first came to my office we talked about just those choices. Her knee was in very bad shape; a large tumor had invaded the bone. This tumor is known as a giant-cell tumor and is not malignant but is very aggressive and destroys bone, just eats it. In Sue’s knee the tumor had already destroyed a big chunk of the knee, and she was in a lot of pain, taking narcotics to sleep at night. It was obvious from the X-rays that her knee was goners; it was destroyed.

It was so bad that in the beginning I thought we should get rid of it, just cut it off. I told her, “You know, an amputation would not be unreasonable here. The tumor is about the size of a grapefruit, and it will complicate any reconstruction work we might try. The safest thing might be to take it off.”

She obviously wasn’t too excited about that, so we started talking about other possibilities. An artificial knee was discussed; she is 32 years old and I explained an artificial joint would most likely loosen in time. The next choice was resection arthrodesis. In a resection, you replace the knee with a section of straight bone and it doesn’t bend. You walk like Chester in “Gunsmoke.”

Now I thought a resection was a good alternative if--and this was a big “if”--I could remove the tumor without destroying the nerves and arteries that feed the lower leg. But Sue held out. She said, “I want a knee that bends.” Well, I explained that there was no standard procedure that would give her a working knee. If she really wanted a new knee, she would have be willing to become a medical pioneer.

The truth is, I would not have offered a transplant to most people, but Sue is very intelligent and very motivated. I knew she could understand what she was getting into, and could deal with the difficulties that lay ahead. I told her I had never transplanted an entire knee joint before; I told her we didn’t even have a donor knee and I wasn’t sure we could get one in time. It took her about 30 seconds to say, “That’s what I want. I’ll take the six months or whatever is necessary to make it work. I want a knee that bends.”

I told Sue we would start looking for a donor. From the X-rays I figured we had about only a little time before the tumor encircled the blood vessels and nerves. When the tumor did that, it would be too late even for a transplant.

I don’t want to imply that this whole thing began in an atmosphere of complete trust. It didn’t. Sue had been seeing doctors for three months without obtaining relief. I think she had lost some confidence in the medical system. When I visited her in the hospital room she would listen politely to what I had to say, but when I left the room she would turn to my nurse, Nancy Tolin, and ask, “Can this guy pull this off? Is he for real?”

There were times when I had the same questions myself. The major problem was getting the tumor out without damaging all those lifelines to the lower leg. I wasn’t sure I could do it. The tumor was large, growing every day, and the blood vessels were wrapped around it. When the radiologist looked at Sue’s X-rays, he said, “Dick, the tumor is very close to the veins and the nerves; they’re all entwined.”

I was also worried about infection. A bone graft is a large piece of tissue that has no blood supply of its own. It’s not like a muscle; you get infection in a muscle, you shoot in antibiotics through the blood supply and take care of it. With a bone (infection) . . . it’s all over, and you lose the transplant.

Meanwhile, of course, we didn’t have a donor knee. I’m the director of the Bone Bank at the University of Pennsylvania Hospital, and I knew what was available. Normally we don’t take the whole knee in a donor situation. The ligaments are removed, the kneecap is removed, and we just store the major bones.

But with Sue we needed the whole thing, plus a approximately six inches of leg bone on either side. And we needed a young knee, one that had a lot of years left. In a situation like that all you can do is wait and hope you get lucky.

We did. On the second day, Nancy Tolin got a call from Kidney One, a Pennsylvania transplant agency. They said an 18-year-old man had been killed in a motorcycle accident and the bones were available. Were we interested? You bet we were.

We arrived at the suburban hospital where the young man had died early that evening but we had to wait for the organ team to finish their work before we could start on the bones. It was probably 4:30 a.m. before we got out.

In this case, I knew exactly what I wanted. A day earlier we had taken one of Sue’s X-rays and marked the cuts on her leg bones. Then we measured the locations of the cuts exactly so we would know how much bone we would need from the donor both above and below the knee. Also I knew I wanted to take the ligaments because this knee had to work in toto. It was like Sue was getting a custom-ordered knee.

I remember we got back to the hospital about 6 in the morning. We still weren’t absolutely sure we had a good knee because it had to pass a test for bacterial infection. But I told Sue anyway; I figured she could use some good news. I said, “We got a knee last night for you and we’re running the tests on it. That doesn’t mean everything is OK. I still don’t know if I can get the tumor out and we are still in the realm of experimental surgery. There are no guarantees.”

I laid a lot of crepe along with the good news and maybe I overdid it. Later on Sue told me that when I left her roommate turned to her and said, “Your doctor is awfully gloomy.” But the great thing about Sue is that she understood.

In the operating room, after I opened Sue’s leg, I took one look and knew that it was going to be even more difficult than I had thought. The blood vessels were literally stretched over the mass of the tumor. Getting them off was going to require a careful dissection technique. When you do this, it’s very easy to tear the vessel wall, especially the walls of the veins.

Veins are very thin, like fettucini, like noodles. They’re slippery and easy to tear and very difficult to repair.

At that point I made the cuts in the bones, so the knee was free to move by itself, and I started slicing. Nancy had the thigh and calf in her arms, holding it up, and a resident was holding the knee section.

I was operating and operating, and moving the knee this way and that way, and it was going real slow. After a while the anatomy started to get distorted because we had rotated it so many times. I was losing my landmarks and it was getting hairy. I remember thinking to myself, I’m not sure I can get this tumor out of here. But I kept going, kept slicing, and eventually it came out.

When we finally lifted the knee and the tumor out, the upper leg essentially was disconnected from the lower leg. Only the nerves and the vessels were linking the two parts. I still didn’t know for sure if I had cut any of the vessels when I peeled them away from the tumor. Up to then a tourniquet on Sue’s thigh had cut off the blood supply. I ordered the tourniquet released, held my breath and waited. The vessels started pumping blood and there were no leaks.

Attaching the new knee was not as tricky as getting the old one out. The top part of the transplant was attached to the leg with a metal rod running inside the thigh bone; the bottom part was set with screws and a plate. We wanted to make sure that the new knee was lined up exactly right, so I had cut a small notch in the front of Sue’s thigh bone and another (locater) notch at the front of the transplant bone. As the glue was setting I lined up the two notches and we knew that everything was straight.

Then we attached Sue’s leg muscles to the new knee and that was that.

With bone transplants, tissue rejection is a potential problem, but I was more worried about infection. All through the operation Sue had been dosed repeatedly with antibiotics, sometimes triple the strength of normal doses. In the operating room I was constantly changing my surgical gloves and my gown to prevent contamination. Still, I knew we wouldn’t know the outcome for several days.

Five days after the surgery, it happened. I was visiting Sue on my rounds and peeled off her dressing. Right there, over her kneecap, there was a small area of dead skin. I knew the battle was not over.

Healthy skin is the primary line of defense against infection. When even a small patch of skin dies, it creates a window for infection. Bacteria would soon march through the opening, get into the transplant and it would be all over.

When I told Sue we had to go back to the operating room, she started crying, and I felt even worse. This knee problem had taken over her life for more than three months and she had hoped that all the bad parts were behind her. Now I was telling her that she was facing more surgery and the threat remained that she might lose her leg. I said, “Sue, don’t bail out now. We’re close, we’ve almost got it. You gotta keep going.”

In the second surgery we reopened the whole incision and irrigated with more antibiotics. I checked all around and satisfied myself that no infection had invaded the transplant. Then we took a muscle flap and skin graft from her thigh, put it over the kneecap to replace the dead skin, sewed it up and started waiting all over again.

This time it worked. So far Sue’s X-rays look real good. She’s at home walking on crutches and I hope she’ll be walking on her new knee in a few months. There’s been no sign of rejection but we’ll keep checking.

In time, we hope that Sue will be able to perform most daily activities with her new knee. She’ll need to avoid really strenuous activities like jogging. One drawback of a transplant is the absence of nerves in the knee itself; if she should injure herself doing strenuous activities she might not know it, and that could lead to further injury.

Many people have asked why I decided to go ahead with a human transplant when trial surgery on animals had proved disappointing. It’s true that the experience with animals had not been promising; the animals experienced a high degree of graft failure. My answer is very simple: Sue is not a laboratory animal. I could explain the process to Sue, tell her that each step in the procedure had to be done slowly and carefully. She listened, she understood, and she did it right. That made the difference.

I do believe that our experience with Sue Lazarchick means there may be a bright future for joint transplants. The procedure wouldn’t work for a football player because the stresses on the new knee would be too great. What the procedure offers is a possible option for people who have very serious problems with their knees. And I hope this surgery, if it remains successful, will encourage other orthopedic surgeons to be more aggressive with transplants. There is a lot of human misery we can alleviate if we have the courage to try.