Freehand

New neural prosthesis can restore movement to paralyzed limbs

A 25-year struggle by researchers at CWRU and local hospitals to help paralyzed people use their hands again has met with success. The Food and Drug Administration (FDA) has approved a neural prosthetic system that allows people with paraplegia to grasp, hold, and release objects by electrically stimulating their muscles. The Freehand System is the world's first surgically implanted device to restore movement to a paralyzed limb.

The system could benefit more than 125,000 adults with paralysis from the chest down due to spinal cord injury. It allows people to live more independently and perform routine activities like eating, personal grooming, and typing on computers so that they can function more fully. The Freehand System costs about $50,000, compared to a possible cost of more than $1.5 million in lifetime expenses for a person with quadriplegia.

Sixty-one people received the system in clinical trials and all reported improvement in their ability to grasp and move their fingers, according to the FDA.

Hunter Peckham, CWRU professor of biomedical engineering and orthopaedics, pioneered the neuroprosthesis. Michael Keith, CWRU professor of orthopaedics and biomedical engineering, surgically implants the components.

The Freehand System is a neuroprosthetic device that includes surgically implanted components and a controller that is worn externally. A joystick-like sensor placed on the chest relaxes and tightens the hand as the shoulder moves back and forth. The system is based on functional electrical stimulation (FES), which delivers minute levels of electrical current to nerves in paralyzed muscles through electrodes placed on or near them.

"The FDA approval is important because it makes the hand grasp prosthesis much more widely available," Peckham said. "With a commercial product backed by the manufacturer, participants in this study are assured of long-term support. Achieving this level of technology transfer and commercial dissemination is a primary objective in our work to develop FES solutions to some of the problems that face individuals with paralysis and make these products available in the clinical setting."

The technology was developed by the Cleveland FES Center, a consortium in functional electrical stimulation research from CWRU, the Cleveland Veterans Administration Medical Center, and MetroHealth Medical Center. Investigators from biomedical engineering, systems engineering, orthopaedics, rehabilitation medicine, and other disciplines make up the CWRU research team.

The National Institutes of Health funded the development of the prosthesis, and the Department of Veterans Affairs provided funds to test the system.

Neural Control Corporation will market the system. Doctors will now be able to prescribe the Freehand System for patients with injuries to the fifth and sixth cervical vertebrae with some upper-body movement. It takes about three months to master the system.

The FES Center is investigating a second-generation neuroprosthesis to restore hand and arm function to people who are paralyzed more severely, first-generation systems to provide standing and leg movement for people with paralysis, and systems to improve control over bladder function.

Peckham said that the FES Center in Cleveland is the major group in the United States doing this kind of research. The area's strength in biomaterials, biomedical devices, and electronic sensors, combined with its treatment programs for individuals with spinal cord injury, are all assets for this type of research, according to the FES Center.