Groundbreaking and even life-altering mobility and rehabilitative devices are proliferating in the United States and internationally. These technologies—including robotic exoskeletons, power-assisted AFOs and KAFOs, hybrid orthoses that use functional electrical stimulation (FES), and brain-computer interfaces (BCI)—are in various stages of research and development, and some have already marched into the marketplace.
"These types of technological advances along with advances in materials science will start to filter into orthotic practices," says Matthew Parente, MS, PT, CPO, clinical director of the University of Hartford, Connecticut, master of science in prosthetics and orthotics (MSPO) program and associate director of the Newington Certificate Program (NCP), also in Hartford. "Advances in the medical community too will likely impact our field…. Orthotists will gain a better understanding and control over how we can utilize our technology."
Since orthotists and prosthetists specialize in working with patients who "wear technology," they can capitalize on expanding their knowledge of these new technologies and skills in adapting them to individual patients, embracing them as part of their scope of practice," points out Christopher Hovorka, MS, CPO, LPO, FAAOP, codirector of the MSPO program at the Georgia Institute of Technology (Georgia Tech), Atlanta.
Robotic Exoskeletons: "I Can Walk!"
By enabling persons with paraplegia due to spinal cord injury (SCI) to stand and walk again, robotic exoskeletons arguably provide some of the most spectacular advances in emerging wearable technology.
Although exoskeletons may also help people with mobility-limiting conditions such as stroke, muscular dystrophy (MD), multiple sclerosis (MS), cerebral palsy (CP), traumatic brain injury, and spina bifida (SB), it is likely to take months and even years of studies to prove the technology's benefits for people with these types of neuromuscular disorders to healthcare payers. The use of exoskeletons by persons with paraplegia, however, demonstrates an immediate, dramatic value, which helps to attract funding and investment, thereby fueling their development.
"We started with paraplegia for several reasons," says Michael Goldfarb, PhD, who heads the Center for Intelligent Mechatronics (CIM) at Vanderbilt University, Nashville, Tennessee. "The technology was there to help persons with paraplegia and should be developed, but also we need to demonstrate to private insurers and Medicare that reimbursement mechanisms are needed so that more persons can use these." The next step, Goldfarb says, is to develop data and appropriate studies that demonstrate health benefits. "It would be great if mobility and quality of life were enough to justify reimbursement, but insurance companies generally want health benefits demonstrated." Exoskeletons won't allow people with paraplegia to completely abandon their wheelchairs; however, such devices will allow some of these individuals to walk for up to several hours at a time, socialize with family and friends at eye level, and enjoy activities and provide access to places that would be difficult to reach in wheelchairs. Being able to stand and walk can help relieve or even avoid serious health issues caused by prolonged sitting, including muscular atrophy, loss of bone density, skin breakdown, urinary tract infections, muscle spasticity, digestive issues, and poor circulation as well as reduced respiratory and cardiovascular capacity.
Four developers seem to be dominating the robotic exoskeleton space: Ekso Bionics, Berkeley, California; Argo Medical Technologies, Yokneam Illit, Israel; Rex Bionics, Auckland, New Zealand; and Vanderbilt University.
The Ekso robotic exoskeleton from Ekso Bionics is currently being used in some U.S. rehabilitation centers. The battery-powered, ready-to-wear device weighs 45 pounds, fits over clothing, and can be adjusted within minutes to fit users who weigh 220 pounds or less. Users do not bear the weight of the device; instead, the device weight is transferred to the ground.
The company, led by CEO Eythor Bender and co-founders Russ Angold, chief technology officer, and Nathan Harding, chief project officer, achieved a major milestone on February 14, as it delivered an Ekso device to Craig Hospital, Englewood, Colorado—the first commercial sale of the robotic exoskeleton.
The Ekso was honored on April 26 with the top prize in the 2012 Edison Awards in the assistive devices category.
Like Ekso, the ReWalk™ from Argo Medical Technologies is currently being used in several U.S. rehabilitation facilities and enables users to climb stairs and navigate inclines. Users' movement is controlled by shifts in the center of gravity and upper-body movements, utilizing sensors and a computer-based control system. A version designed for individual patient use, the ReWalk-P, will be released in Europe later this year and in the United States upon U.S. Food and Drug Administration (FDA) approval, according to Amit Goffer, PhD, designer of the device and company co-founder.
Rex Bionics sold the first commercial model of its Rex robotic exoskeletal legs last year to Paralympic champion Dave MacCalman of New Zealand, who had not been able to walk in three decades. "It is hard to describe what it has been like to be back on my feet again. I'm six-foot-four, so it's been amazing to experience life from that height again," MacCalman is quoted as saying in a company press release. Rex is operated by a joystick that is built into its armrest, so unlike other leading exoskeletons, the device does not require forearm crutches or arm strength. Rex Bionics has since sold several exoskeletons outside the United States and is currently seeking FDA approval to market personal models in the United States, according to the Fast Company article, "Ekso's Exoskeletons Let Paraplegic's Walk, Will Anyone Actually Wear One?" by Ted Greenwald (March 19, 2012).
The Vanderbilt Exoskeleton developed by Goldfarb and his team is ready for "prime time" and is going through the commercialization process. The system is "very easy and intuitive to use," Goldfarb says, with "no buttons to press. Use it somewhat like a Segway®—lean forward when you want to go forward," he explains.
The Vanderbilt Exoskeleton can be donned and doffed from a sitting position and snaps apart into three pieces, which fit into a knapsack. The device also allows for use of FES if the user chooses, simply by applying sticky electrodes to appropriate muscles and plugging the electrodes into a module. The device has potential to help persons with incomplete SCI, stroke, and other conditions; Goldfarb sees pediatric applications, especially for children with CP to help train their musculoskeletal system to have a healthy gait. "The brain is fairly plastic and can 'rewire,' but once the musculoskeletal system is developed, then it's much harder to correct poor gait."
Access through Affordability
Most medical-use exoskeletons currently cost upwards of $100,000 each, and as is true with many technologically advanced mobility and rehabilitative devices, cost can become a barrier to use. However, the University of California, Berkeley (UC Berkeley), Austin Project aims to make exoskeletons more economically accessible to individual users. Homayoon Kazerooni, PhD, professor of mechanical engineering and director of the Berkeley Robotics and Human Engineering Laboratory, challenged his students to create a device that would cost $15,000 or less. The project, named in honor of its first test subject, Austin Whitney, began in 2009 and quickly became an obsession with students of Kazerooni's "Kaz Lab," according to the article "First Steps of a Cyborg," posted August 30, 2011, on PopSci.com (www. popsci.com/technology/article/2011-08/ first-steps-cyborg?page=1). Whitney has paraplegia as the result of injuries sustained in a high school automobile accident. Using off-the-shelf parts, such as snowboard bindings, soccer shin guards, and a $60 microprocessor, the students created a minimalist device. The students worked 17-hour days as the assignment due date—graduation day—approached. Although Whitney is not an engineer, his input was critical to the Kaz Lab team, the article notes, adding, "He has participated in hundres of tests and provided design suggestions, user feedback, and motivation." On graduation day, the students celebrated their success as Whitney walked across the stage last year and received his diploma to the accompaniment of a standing ovation from the audience of 15,000.
More Breakthroughs at Berkeley
This is not Kazerooni's maiden voyage into the land of exoskeleton R&D. Before the Austin Project, and bolstered by funding from the Defense Advanced Research Projects Agency (DARPA), Kazerooni and his team developed the Berkeley Lower Extremity Exoskeleton (BLEEX) in 2004. In 2005, Kazerooni co-founded with Angold and Harding Berkeley ExoWorks, later renamed Berkeley Bionics, to further develop and commercialize the technology. In 2008, the company unveiled the Human Universal Load Carrier (HULC), which the company later licensed to Lockheed Martin Corporation for further military development. In 2010, Berkeley Bionics introduced eLegs, a robotic exoskeleton enabling wheelchair users to walk. In 2011, the company became Ekso Bionics with the focus of developing exoskeleton technology for medical and rehabilitation use.
Although no longer connected with Ekso Bionics, Kazerooni and his team at UC Berkeley are using the Austin Project as a jumping-off point to develop lightweight, accessible robotic technologies at low cost. They hope to bring manufacturing costs down to the level of a powered wheelchair, Kazerooni says.
Robotics: Function with Recovery?
An exciting question, to which the answer is still something of an unknown, is whether or not robotic therapy aids in motor recovery over and above simply enabling increased motor function?
A thought-provoking study, "Motions or Muscles? Some Behavioral Factors Underlying Robotic Assistance of Motor Recovery," by Neville Hogan, PhD, et al. (Journal of Rehabilitation Research & Development, vol. 43, no. 5, pgs. 605–18, August/September 2006) points out, "Though many details of the biology of recovery are unknown or controversial, the combination of clinical and animal studies indicates that motor activity of appropriate structure and intensity enhances or guides a neuroplastic recovery process after brain injury. An underlying activity-dependent neural plasticity is probably a key mechanism through which robotic therapy produces clinical benefits…. A preponderance of evidence now available indicates that appropriate forms of robotic therapy can provide significant benefits."
Regarding robotics and other modalities including FES and BCI technologies, a 2011 paper, "Rehabilitation of Gait after Stroke: A Review Towards a Top-Down Approach," (Belda- Lois et al. Journal of NeuroEngineering and Rehabilitation 2011, 8:66) indicates that the clinical effectiveness of these modalities is promising, but more research is needed:
- Regarding classical rehabilitation techniques (neurophysiological and motor learning approaches), there is insufficient evidence to state that a particular approach is more effective in promoting gait recovery than another. A combination of different rehabilitation strategies seems to be more effective than over-ground gait training alone.
- Robotic devices need further research to show their suitability for walking training and their effects on overground gait.
- The use of FES combined with different walking retraining strategies has resulted in improvements in hemiplegic gait. Reports on non-invasive BCIs for stroke recovery are limited to the rehabilitation of upper limbs; however, some works suggest that there might be a common mechanism that influences upper- and lower-limb recovery simultaneously.
- Functional near infrared spectroscopy (fNIRS) enables researchers to detect signals from specific regions of the cortex during performance of motor activities for the development of future BCIs. Future research would make it possible to analyze the impact of rehabilitation on brain plasticity in order to adapt treatment resources to meet the needs of each patient and to optimize the recovery process.
In discussing robotic technology, Hogan et al. highlight the clinician's role and bring up points that can be applied to other advancing technologies as well: "Though further improvements may reasonably be expected, the limitations of robotic technology should be acknowledged. For example, endowing a machine with the compassionate insight about an individual's needs that a skilled clinician provides would be difficult…. In our view, robotics is no more than a toolset, albeit one with great versatility, that improves the resources available to clinicians as they facilitate recovery. The best treatment for an individual patient is most likely to be a combination of robotic therapy and other approaches."
The authors stress that clinical studies of new technology are necessary to establish which approaches are effective for which patients and to identify optimal treatment schedules to better serve patients. Such studies could capitalize on opportunities to conduct therapy in new venues, such as the home, and new ways to understand the biology of recovery, such as via the Internet and through fundamental research. "Of course, these efforts are related: a deeper understanding of the recovery process will guide and inspire technology development, which in turn provides material for clinical evaluation," the authors state.
Confronting R&D Challenges
The biggest challenge in developing new technologies is, simply and not surprisingly, money.
"There are certainly tremors of some exciting technology on the horizon, such as multi-channel FES systems and exoskeletal powered orthoses for paraplegia," observes Phillip Stevens, MEd, CPO, FAAOP. Stevens is a clinician at Hanger Clinic, Salt Lake City, Utah, and is a member of the American Academy of Orthotists and Prosthetists (the Academy) board of directors and its Research Council. "But their timing is unfortunate. These developments appear to be hitting the marketplace at a time when funding sources are becoming increasingly stingy," he says, adding that the last time the Centers for Medicare & Medicaid Services (CMS) added a new orthotic L-Code was in 2005.The political and legal motivators driving reimbursement for new prosthetic technologies have not existed for advances in orthotics, he points out. Persons suffering amputations in military combat or in work-related accidents have funding sources that are compelled to pay for emerging prosthetic technologies. Thus a "critical mass" of early users of these technologies demonstrates their value to a larger group of patients and payers, which has not been the case in orthotics, Stevens explains.
Today's Orthotists: Preparing for the Future
While the case to support the use of robotic exoskeletons and related devices in a rehabilitative or clinical orthotic setting is being built through research studies and clinical trials, it's critical for the O&P profession to get in on the ground floor. This can begin with building and maintaining an awareness of technological advances so that the profession can help to find ways to apply technology to O&P devices and practice. As Parente points out, "For instance, there's much more research going on in materials science in general than in O&P-specific materials science. When we see something new, such as in battery technology and new sensors and microprocessors, we look for an application for O&P.
Parente continues, "At the University of Hartford, we're incorporating orthotists and prosthetists into our engineering and physical therapy research projects, not just in our multidisciplinary patient care. When certified orthotists and prosthetists are incorporated into the initial research phase, we can look at the patient application earlier in the process. So if an engineer solves a problem, but the solution isn't practical to patient care, then we have to go back to the drawing board to make it clinically relevant."
To help established and future clinicians be prepared to use new technologies, Parente advocates for building a strong foundation in orthotics principles and practice and then being flexible and willing to try new technologies in clinical practice. He highlights the importance of being informed consumers of research and evidence-based practice (EBP), as well as keeping up to date through continuing education courses. "As we move into a different realm of healthcare payers and EBP…these factors…all come together to enable clinicians to keep up with advancing knowledge and technology," Parente says.
Robert Rhodes, MPA, CO, FAAOP, director of the Orthotic-Prosthetic Programs at Eastern Michigan University (EMU), Ypsilanti agrees. He says he believes in helping orthotics students to maintain an open and eager mindset and always look for new and better ways of doing things. He encourages his students to keep up with continuing education after entering the field, especially since technologies are continually changing and what is learned in school today may not apply tomorrow.
To help students develop flexible thinking skills, Rhodes tried using problem-based learning, which has been defined as "students connecting disciplinary knowledge to real-world problems." In this approach, which is also being used in EMU's physician assistant program, the desire to solve a problem becomes the motivation to learn. "Some did well, and some didn't," Rhodes says. He adds that faculty members should be open to input from students as well.
Students are encouraged to think "out of the box" for solutions, Rhodes says. "For instance, we didn't have a bubble-forming machine, and one of our students thought we needed one. So he created one. And guess what he used—an old cast-iron frying pan!"
"It works great," Rhodes adds.
"University-based master's and doctoral-level P&O programs are now set to become the 'bridge' between orthotics innovation, clinical research, orthotist training, and clinical practice, says Kevin A. Ball, PhD, the University of Hartford's associate dean for Graduate Studies and Research, College of Education, Nursing, and Health Professions, and associate professor and academic director of the university's O&P education program. Ball points out that universities possess unique laboratories and equipment—not to mention a ready pool of researchers— to advance research for EBP. "At the University of Hartford, and at other university programs throughout the country, industry partnerships are being formed for development and clinical trials testing of P&O technologies," Ball says. "Universities are eager to play a significant role in furthering clinical practice skills through the provision of post-graduate training opportunities."
Miki Fairley is a freelance writer based in southwest Colorado. She can be reached at firstname.lastname@example.org