New Frontiers in Spinal Cord Injury Research
P. Hunter Peckham, PhD, director of the FES Center, tells WebMD that he and his colleagues have been working for "about 30 years with functional electrical stimulation."
The nervous system operates by means of electrical impulses, which pass information from one nerve to the next. With this system, a stimulating device is used to pass electrical information along and amplify the impulse, even when the nerves are severed, thus bypassing the point of injury and using the nerves' natural electrical activity that is still in place.
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.