Likewise, physical therapy and assistive devices also have improved, greatly expanding the boundaries of what people with spinal cord injury can accomplish in their lives.
But what has not changed -- and what Hinderer has set his sights on -- is the cast-in-stone notion that the function of the spinal cord itself will not improve below the point of injury after one year. It's considered impossible in all but 5 percent of cases.
As a consequence, conventional rehab is aimed at helping people make the most of the muscles and feelings that still work.
"We have to move the mark,'' Hinderer said.
Hinderer described three experimental approaches that have shown promise, including:
-Implanting adult olfactory stem cells that are taken from the roof of the patient's own nasal cavity.
The normal function of these stem cells is to replenish olfactory nerves, which give the sense of smell. (Olfactory nerves are the only nerves in the body that are rapidly replenished by stem cells the way that blood cells, for example, are, Hinderer said.)
Lisbon surgeon Dr. Carlos Lima's procedure is to put them in the spinal cord in the hope they'll replenish lost nerve fibers there.
The "aggressive'' operation involves opening the patients' spine, removing scar tissue from the injury site and inserting the cells.
Other important "helper cells'' called glia are harvested along with the stem cells and implanted. These may also aid in recovery.
-Injections of immune cells called macrophages into the cord soon after injury to promote healing. Macrophages aid healing by removing dead cells and debris and by sending out signals that recruit other natural healing factors to the site.
In most spinal cord injuries, the cord is actually crushed rather than being severed, Hinderer said. The bruised area does not heal well, partly because macrophages are not as prevalent in the cord as in other parts of the body.
-Researchers at Indiana University School of Medicine, in Indianapolis, are experimenting with the use of magnetic fields to coax nerve fibers to grow across the damaged spot in the cord.
IU researchers have implanted electromagnetic devices in sea lampreys, rats and dogs and more recently in 10 people.
While Hinderer's program evaluates candidates for the Lisbon procedure, he does not endorse it. No scientifically valid data has been reported to prove that it works, he said.
"I can't advise people to do it or not to do it,'' he said. "That's what I told Joey and Steve (McTigue) when they were up there.''
He does, however, endorse the safety of the operation. Of the 80 people who have had the implant, two suffered infections and recovered after treatment. Additional precautions are now taken to prevent infections by pretreating patients for bacteria present in their nasal cavity.
Spinal cord injuries affect a relatively small number of people -- about 11,000 new injuries annually in the United States.
But the vast majority are young, and the impact of their paralysis is huge in terms of lost productivity and reduced quality of life.
"This is an injury of the young, and most will live a full life span,'' Hinderer said. "We need to find ways to help them recover.''
Staff writer David Rumbach:
drumbach@sbtinfo.com
(574) 235-6358