DAYTON, Ohio -- Nan Davis, 22, with her crippled legs wired to a computer that controlled electrical stimulation, took six slow steps Thursday to become the first person with totally paralyzed legs to walk.
'It was fantastic,' Ms. Davis said after her hesitant but historic steps. 'I feel like a pioneer. This is history, the first time it's ever been done.'
While Ms. Davis' walk at Wright State University's scientific laboratories was historic, it was far from normal walking.
She was strapped into a parachute harness that supported one-third of her weight, wore paratrooper boots to protect her fragile ankles and gripped parallel bars as she made her way carefully down a 10-foot walkway.
Despite the aids, the movement in her legs demonstrated that technology is being developed to stimulate and control paralyzed limbs.
Ms. Davis' walk was made possible by what is known as a 'computerized electrical stimulation and feedback system.'
Basically, the system involves electric current controlled by a computer to produce movement in otherwise motionless muscles.
Electrodes were taped to the skin over major muscle groups in Ms. Davis' legs. A computer was programmed to order successive, millisecond bursts of electrical stimulation to the appropriate muscles at the right times to produce walking.
Ms. Davis, a senior at Wright State from St. Marys, Ohio, was paralyzed from the rib cage down four years ago in an auto accident on her high school graduation night.
'When they told me I wouldn't walk again, I said, 'Yes, I will,'' recalled Ms. Davis.
However, her progress really didn't begin until six months ago when she began working with Dr. Jerrold Petrofsky, in charge of the Wright State Biomedical Engineering Laboratory.
'To my knowledge,' Petrofsky announced after Ms. Davis' walk, 'this is the first time a totally paralyzed person has walked.'
Petrofsky has been working the past 13 years to reach this point, but he figures several more years are needed before he comes close to his ultimate goal.
Petrofsky hopes paralyzed people eventually can walk free-standing, with microprocessors (tiny computers on chips) implanted near their paralyzed muscles. Such a system would be similar to a heart pacemaker.
'We aren't trying to invent a cure-all,' noted Petrofsky. 'This is not a cure for paralysis. It is a bypass. We're trying to liberate people from wheelchairs.
'This is kind of a pun, but today is just really another step forward and is only the beginning of walking research.
'I still think it will be around 10 years at best before a walking device like this would be available commercially.'
