Six inches. That's the distance between 19-year-old Nick Anderson and his dream of driving NASCAR racecars. It's also the length of nerves ripped out of his left arm after an accident, leaving his hand paralyzed and unable to grip a steering wheel.

And it's the length of several nerves donated by his mother, Frankie Anderson-Harris, and stitched into Nick's arm yesterday in a rare, seven-hour-long operation to restore movement to his hand. The surgery can not only keep Nick's racing dreams alive but also let him keep his arm.

"After the accident, doctors wanted to cut off his arm," his mother recalls. "They said it would just get in his way, since he couldn't move it, and he'd be better off without it. I had to fight them pretty hard. None of them had ever thought of nerve transplants."

"Doctors generally don't know that we've made remarkable strides in nerve surgery," says Allan Belzberg, Nick's surgeon at Johns Hopkins Hospital in Baltimore. "So there are limbs being cut off unnecessarily, and we want to get the message out: Don't cut until you've talked to us."

Nerves, treated properly, will grow back, Belzberg says. Two years ago, he operated on a soldier who had a big nerve in his upper leg shot away in Iraq, paralyzing the limb. Belzberg was able to take another nerve from elsewhere in the body and carefully splice it into the gap, like making a connection between two wires. The transplanted nerve originally transmitted sensations, not commands for movement, but it adapted to its new situation. Within a few months, the soldier, Derrick Goodrich, could stand and flex his knee.

"Today he's walking," Belzberg says.

Nick Anderson's case is even more complicated, because he doesn't have enough long nerves left to donate to himself. The car accident last December that shattered his arm also shattered one leg and tore off the other one. (He walks with a prosthesis now.) That means he has only one intact limb, his right arm, and doctors didn't want to risk impairing it by taking out nerves. So he needed a donor.

Everyone in his family stepped forward. But Frankie, his mother, was the closest tissue match.

"Hey, I was willing to give up movement nerves, or the use of my arms, if it would help. He's my son," said Frankie yesterday in a Hopkins Hospital waiting room, while Nick was undergoing surgery. She was rubbing her arms and legs, because Belzberg had taken out lengths of sensory nerves from those spots. "I'm going to have some small numb spots, but that's no big deal."

In the operating room just down the hall, Belzberg was laying out several of Frankie's nerves, thin and delicate strands, in the gap between the stumps of Nick's movement nerves. Because sensory nerves are so much smaller than movement nerves, he had to weave in four of hers for every one of Nick's. It is painstaking work, and Belzberg stares through a microscope as his forceps tease out the tiny strands to be connected.

"My nerves are going to be like a straw," Frankie explains. "Once Belzberg places them in, Nick's own nerve fibers will grow through the hollow center and eventually reconnect." The regrowth is the big advantage of this operation. Nick will have to be on immunosuppressive drugs to keep his arm from rejecting the transplant, but not for life. He'll only have to stay on them until his own nerves grow back, which should take about a year. And that's when everyone will know if the operation worked.

Nick, the day before surgery, was optimistic.

"I think there's a very good chance of it working. They've done a handful of successful ones before, at Barnes Jewish Hospital in St. Louis," he said. "I looked them up on the Internet. I also looked into stem cells, and computerized prosthetics, but this seemed like the best bet." After 15 surgeries during the past 10 months, he's become pretty knowledgeable about medicine.

"I'm not too nervous about the surgery. And I'm looking forward to driving a racecar again." His grandfather, who owns the car, is already hatching plans to modify Nick's artificial leg with a boot so he can work the gas pedal more easily. "I've been racing cars since I was 6. I love doing it. It's pretty much my life."