What are the basic technologies involved in functional electrical
Essentially, FES uses electrical stimulation to activate nerves and ultimately
restore some function of the body that has been lost through injury or illness.
For example, the Freehand system developed here at our FES Center uses an
implanted electrical stimulator together with implanted electrodes to activate
muscles in the hand and forearm. This enables paralyzed patients to grasp and
How is the field developing—in terms of adding
new applications? Some researchers now make the distinction between neurostimulation, such as the example I just gave, and neuromodulation, which uses electrical stimulation to activate whole populations of cells. An example of the later would be deep brain stimulation, such as the implant developed by Medtronic to control tremors in Parkinson's patients.
What are some of your projects? If you go to our website (http://feswww.fes.cwru.edu), you'll see descriptions of more than 40 research and clinical programs. These include several to aid those who have suffered spinal cord injuries, such as systems that allow individuals to stand and take steps, or that relieve pressure sores, alleviate breathing problems, or control bowel or bladder functions. For the broader population, our research ranges from devices to counter sleep apnea to those that relieve shoulder pain in stroke victims or retrain muscles paralyzed as a result of stroke. Still another device under development seeks to improve vision in patients with involuntary eye movements, sometimes associated with multiple sclerosis.
Are you close to commercialization? We are constantly seeking commercial partners to bring these technologies forward. One of the big developments for our program over the past couple years has been funding assistance from the State of Ohio aimed at helping us bring more of our technology to the prototype stage where it would be of interest to commercial partners. These funds are focused particularly on systems aimed at four areas of concern: sleep apnea, pain relief, motor control in stroke victims, and urinary incontinence.
What major improvements are needed in FES
systems? Certainly, we need to engineer systems that can be produced more economically. These devices also need to be more transparent and user-friendly for patients. Take the Freehand system, for example. Older versions required the patient to wear a shoulder-mounted exterior positioning sensor, which obviously was difficult for someone with paralysis to put on every day. Our latest version employs an implanted sensor array in the forearm, which is both extremely reliable and more acceptable to patients. Beyond that, rather than design systems for just one or a few applications, we are trying to develop basic FES modules that can be used in several applications. Medtronic has done an excellent job of leveraging the same basic technology in applications for pain relief, urinary incontinence, and deep brain stimulation. Ideally, we want to develop systems that would have the power supply and all sensors inside the body.
Peckham, a Ph.D. biomedical engineer, is a former Design
News Engineer of the Year. He has pioneered technologies based on functional
electrical stimulation for more than 30 years.