The Next Step in Robotic Rehabilitation Technology
By Mike Bonner, vice president, Neuroscience
Since the 1990s, the robotic engineering field has grown exponentially. Originally developed for military purposes, wearable robotic exoskeletons previously designed to augment their user’s strength and mobility now offer significant promise as medical assistive devices. This is especially true for patients with lower-extremity paralysis.
During locomotion, the movement of the legs in the sagittal plane is relatively simple and repetitive, making it ideal for machine support. Robotic exoskeletons can be programmed to run short sub-routines that control the device as it moves the patient’s legs through push-off, transfer of weight and forward movement during the gait cycle. After years of trials and continued design refinement, these robotic exoskeletons now closely approximate natural gait and are ready for clinical debut.
In 2011, Ekso Bionics (formerly Berkeley Bionics) announced a partnership with Good Shepherd Rehabilitation, one of 10 initial partners selected to conduct trials with the Ekso bionic exoskeleton . The Ekso, formerly eLEGS exoskeleton, is a robotic device that was recognized by CNN and TIME magazine as a Top Innovation and as one of Wired’s Top 10 Gadgets of 2010. Ultimately, the goal is to make Ekso accessible and affordable for patients as an everyday mobility device.
The clinicians at Good Shepherd first used the Ekso in clinic in 2011 as part of a trial with eight neurorehabilitation patients. In March, Good Shepherd became the third organization in the country to receive its own Ekso for use in therapy. Good Shepherd will join the other Ekso sites in the U.S. in monitoring patients as part of research on Ekso users’ potential physical and emotional health benefits. For the patients at Good Shepherd, that translates into the ability to see the world standing up again.
The Ekso exoskeleton is a battery-operated robotic unit that is strapped on over the patient's clothing. The combination of motors and sensors, along with patient assist with balance and body positioning, allow the user to walk over ground with reciprocal gait. An on-board computer commands motors at the hip and knee to move the patient’s legs through a smooth, natural heel-toe gait.
Patients work with therapists and the device to learn to maintain balance and transfer weight as they step. At first, the interface will be controlled by a therapist, working alongside the patient. As the movement becomes more natural and patients are better able to support their weight, they can progress from use of the Ekso with a walker to use in combination with Lofstrand crutches.
Appropriate users of the Ekso exoskeleton have lower extremity weakness due to spinal cord injury , Guillain-Barre syndrome, multiple sclerosis or generalized lower extremity weakness. The device requires the user to provide balance and progression control, and it requires reasonable upper extremity strength for proper ambulation. Appropriatecandidates are between 5'2" and 6'2" and less than 220 pounds, and they must be proficient with balance and transfers from wheelchair to other surfaces. In addition, candidates also will have sufficient range of motion, as well as adequate cognitive skills for participation in the rehabilitation program and mastery of the device.