New Frontiers in Spinal Cord Injury Research
Using this principle, Peckham's team worked out a way to deliver electrical
stimulation in a way that could be tolerated by the patient. They decided to
start by implanting the stimulator in tissues near the point of injury, rather
than using external stimulation. The main drawback with external or surface
stimulation, says John Chae, MD, MS, is that few patients can tolerate
sufficient energy to get adequate deep muscle stimulation. Chae is an assistant
professor at Case Western Reserve University School of Medicine and the
director of stroke rehabilitation at MetroHealth. Peckham says that too much
surface stimulation not only can cause burns, but can also result in
uncontrolled leg movements.
Thus far, two implantable stimulators developed by Peckham's team are
approved by the FDA. Vocare -- a device facilitating bladder and bowel control
that has been implanted in more than 1,600 paralyzed patients -- and Freehand,
a stimulator that permits patients with a neck spinal injury who have some
shoulder control to open and close a hand for grasping and holding objects, are
manufactured by NeuroControl of Cleveland.
While these may seem like impressive accomplishments, they are just the
beginning of what may be a 'golden age' of spinal research. David Yu, MD, an
assistant professor of medicine at Case Western Reserve, is principle
investigator of an NIH- and VA-funded study that will, for the first time, look
at whether it is feasible to help people with high neck injuries who have
virtually entire body paralysis. "This is an injury like Christopher
Reeve's injury," Yu tells WebMD. "Thus far we have [operated on] five
limbs of three subjects," Yu says. "We've demonstrated that we are able
to generate a response in one of the three subjects," he says.
Although this work is very preliminary, Yu says that he sees it as a
necessary task to prepare the next big step in spinal cord research: a link-up
between those working in functional restoration, such as the Cleveland FES
Center, and biologic researchers who are concentrating on nerve regeneration.
Yu says that nerve regeneration has just "really taken off in the last 10
years, because it's only in the last 10 years that it has been apparent that
something can be done."
The studies now underway in Cleveland, such as Yu's study, will become
especially useful in an era "when we have incomplete spinal cord
injuries," says Yu. If nerve regeneration is successful in the future, it
is likely to lead to only partial restoration, which will mean incomplete
spinal cord injuries. In that case FES becomes even more important, as
stimulation can be used not only to strengthen muscles but also to help nerve
pathways begin working again, Yu says.
The Cleveland team is hoping to put this theory to the test in a joint
project with nerve regeneration researchers. The first steps toward that goal
are preliminary talks slated to begin later this spring with researchers from
Washington University in St. Louis.