Experimental Procedure 'Rewires' 6-Year-Old's Nervous System

March 29, 2010— -- Six-year-old Alex McShane of Phoenixville, Pa. lost the use of his right arm six months ago. But thanks to an experimental surgical procedure that effectively rewired the nerves in his arm, the paralysis may be reversible.

During a five-hour surgery Tuesday morning, doctors harvested functioning nerve tissue from Alex's leg and used it as a graft to reroute a nerve in his shoulder to instead control his right arm.

If his recovery goes as planned, Alex will be able to "bend his arm with a different nerve than he was born with," said the boy's surgeon, Dr. Allan Belzberg, an associate professor of neurosurgery at the Johns Hopkins University School of Medicine in Baltimore.

"We plugged the graft into the nerve that bends your elbow so when he thinks 'shrug my shoulder,' his arm will bend," Belzberg said. "Over time, because he's so young, his movement will smooth out as he relearns [how to use his arm]."

Alex's arm was paralyzed in the fall after he was stricken with transverse myelitis, a rare auto-immune disease in which the immune system attacks and damages the nerves of the spinal cord.

After what was thought to be a bout of strep throat in September turned out to be the beginning stages of transverse myelitis, Alex's right arm went slack, followed by his neck, left arm and leg, and his diaphragm.

"We took him to the ER on Sept. 26, and we haven't been home since," mom Angela McShane, 39, said.

While Alex regained control of his neck and left side and a bit of his right hand, it seemed unlikely that his right arm would come back on its own, McShane said. So she and husband Sean, 40, agreed to the surgery, wanting to give their son "every opportunity to get better," she said.

Belzberg is the first surgeon to attempt this kind of nerve rewiring on transverse myelitis patients and Alex's surgery was only the third time the procedure had been attempted.

"The surgery went well," Belzberg said.

McShane said Alex "is doing amazing," but there will be months of recovery before the success of the surgery can be gauged.

New Hope in Old Nerves

Chances of getting transverse myelitis are literally one in a million, said neurologist Dr. Daniel Becker, who heads pediatric restoration therapy at the Kennedy Krieger Institute in Baltimore.

While it's not completely understood what causes it, the condition, as in Alex's case, is often triggered by a viral infection.

The inflammation associated with transverse myelitis comes on rapidly, sometimes within hours, otherwise within days, Becker said.

What begins as a sudden onset of lower back pain, muscle weakness and strange sensations in the extremities progresses to impaired movement and paralysis in various parts of the body and loss of bladder and bowel control.

About a third of patients will regain most of their nerve function, a third will have moderate nerve damage and the remaining third will have significant permanent damage, Becker said.

In Alex's case, "his recovery was quite poor," and he was left with severe weakness on his left side, breathing difficulties and paralysis of his right arm and shoulder, Belzberg said.

While steroids are administered to reduce the inflammation in the early stages, once the damage is done, the only treatment is aggressive physical therapy to try to increase the function of the remaining healthy nerves.

If the nerves haven't healed on their own within the first three to six months, it is unlikely they ever will, Belzberg said. Six months out, Alex was at the point where the chances of his regaining function were "very, very poor," he added.

This is where Belzberg's novel surgical approach came in.

Playing Connect the Nerves

"Basically, I'm robbing from Peter to pay Paul; look for something that's working so I can rob at least part of it to help where something's not working," Belzberg said.

While rewiring healthy nerves to do the work of defunct ones is a technique used for many years, Belzberg is the first to treat transverse myelitis this way.

If successful, the procedure will restore movement to Alex's right arm, with virtually no adverse effects.

"It certainly won't be normal function [of the arm] but it should eventually have a smooth bend," he said.

In the bargain, Alex will lose some of the strength in his right shoulder where the nerve was rerouted and he will have a numb patch on his left foot where sensory nerve fibers from Alex's left leg were taken for the graft, but these should be the only effects.

The procedure is certainly not without risk, however, Belzberg said.

"This is a technically challenging and demanding operation," he said. "Everyone's wired slightly differently and you have to figure out how to hook the nerves together. There's risk that you're going to damage other nerves that are still functioning or the blood vessels that go with those nerves."

"Now that he's through the surgery … and doing great, of course, I can say I'm glad we did it," McShane said, but the decision was a difficult one to make. "He was doing really well [with the pain and breathing] and we were hesitant to put him through that and possibly set back his recovery."

After a post-op check, it appeared that no further damage was done to Alex's nerves during the operation, and he was up and walking again two days later, McShane said.

Belzberg said, "Now we have to wait an enormous amount of time for the nerves on the inside to regenerate."

This occurs at the rate of one inch per month, so there will be a six- to eight-month lag before any changes will be detectable in Alex.

"Once the changes appear, we'll use aggressive physical therapy to strengthen the arm and help with the coordination," he said.

Becker, who directs this kind of restorative therapy at Kennedy Krieger's International Center for Spinal Cord Injury, said Alex is lucky to have youth on his side.

"You'd think it would be strange" to have the nerve that is supposed to move one muscle now control another, he said, "but the nervous system is very plastic. It learns quickly and the younger you are, the easier the learning curve."

Although he has months of recovery stretching ahead of him, McShane said, Alex "is a trooper."

"He's only 6 and he's been through so much [but] his personality is completely the same, he's the same kid. He has a spirit that cannot be broken."