By Stefan Dubowski
You may remember Robbie the Robot from Forbidden Planet, C-3PO from Star Wars and Rosie from The Jetsons.
You may remember Robbie the Robot from Forbidden Planet, C-3PO from Star Wars and Rosie from The Jetsons. Robots often play central roles in science fiction entertainment. Thanks to the work of one doctor, they could soon feature in chiropractic treatment.
Dr. Greg Kawchuk, DC, is the Canada Research Chair in Spinal Function and a professor in the Faculty of Rehabilitation Medicine at the University of Alberta. He and a team of undergraduates, graduate students and post-doctoral fellows use a robot to investigate chiropractic treatments for people with back pain and muscle weaknesses. Their work could inform chiropractic treatment in the future.
The doctor and his team use a robot, which looks like a coffee table on six legs, to challenge a patient’s posture and measure the results.
“Those legs can be programmed to move in certain ways such that the tabletop can move up, down, tilt… anything you want,” Kawchuk says. “It’s the same technology you’d put under an airplane cockpit to create a flight simulator.”
Researchers have a person stand on the device’s platform. The subject wears 10 to 12 sensors that detect muscle activity, and a laser pointer affixed to the head or chest. He or she is instructed to focus the laser on a point on a wall while the robot tilts and turns the platform.
“The person has to fight really hard to maintain the laser on the target,” Kawchuk says. Meanwhile, the team monitors muscle activity in the individual’s trunk.
“We can see if someone is perhaps not firing their muscles appropriately or not using their muscles, or if they have too much over- or under-compensation when it comes to adjusting for their posture.”
Once they understand where the person has muscle weakness, the researchers can program the robot to move in a way that helps the individual strengthen those muscles. The researchers can also program the robot to mimic real-world situations. This replay capability enables Kawchuk and his crew to zero in on what causes a patient’s back pain. For instance, the researchers can record how a bus driver’s seat moves during a bus route. That information can be downloaded to the robot, which recreates the seat’s movements. A bus driver can then sit in the robot, which gives the researchers the chance to measure how the driver’s muscles react throughout a typical drive.
Kawchuk was inspired to mix robots and chiropractic as a graduate student of biomechanics and bioengineering at the University of Calgary in the 1990s.
“I was looking for the best tools to understand how to investigate the motions of spinal segments and of whole people,” he says. The university had a simple robot on campus. The machine certainly wasn’t intended for chiropractic research. Engineers used it to manoeuvre industrial material around a stationary tool to shape propellers and other complicated forms.
Kawchuk decided to use it for something entirely different: replicating human joint movement. He applied his research to the study of spinal stiffness, completing his PhD on that topic in 2000. In 2004, Kawchuk joined the University of Alberta in Edmonton for further robot research. Soon after arriving, he acquired the machine he uses today.
Kawchuk’s research invites the question: Will chiropractors have robots in their own offices one day?
It’s not as far-fetched as one would believe – after all, prices for these devices are decreasing. Kawchuk figures the machine that the University of Alberta bought for $200,000 seven or eight years ago would cost $30,000 to $50,000 today.
Nonetheless, he doesn’t think the average chiropractor will own a robot. Despite the declining cost, the high price tag remains a barrier to widespread adoption. Manufacturer Mikrolar Inc., which made Kawchuk’s machine, says the price of its products still range as high as $500,000.
Education is another challenge. It takes significant training to operate a robot effectively. That’s an ongoing concern for Kawchuk. His team includes students who become experts in programming the device, but these technicians inevitably move on to other studies or careers, leaving Kawchuk to constantly train newcomers from scratch.
Given all that, Kawchuk envisages a communal solution that involves a single robot housed in a facility where clinicians could send patients for evaluations.
“We can do this on a limited basis as a research initiative,” he says. “But to make it something that is commercially available, we’re probably a ways off from that yet.”
In the meantime, Kawchuk has a few difficulties to address, such as how to speed up the knowledge transfer from trained robot technicians to new students. He thinks he has a solution.
“We now have an ongoing manual used and added to by each student, so the next person benefits from the work and experience of their predecessors.”
He’s also concerned about the robot itself. Kawchuk has been using this current machine for eight years. More modern iterations are available today.
“We’re trying to get an upgrade so we can do whatever we need to do,” he says.
It’s not as if his team has discovered functional limitations with the existing device, but the robot’s software will become obsolete, eventually. At that point, the apparatus will have to be replaced.
Kawchuk and his team also have to think about the next step for their research. They plan to connect the dots between what they know now and what chiropractors can do with that information.
“We have the initial evidence that the robot can find these problems and train them, but we need a larger trial to show the profession what the impact would be. That’s something we’re working on.”
Perhaps Kawchuk’s biggest concern is that his research plugs into the larger medical trend of identifying the best treatment for each person, individually.
“We’re trying to develop personalized health care so we get the right therapy to the individual and make their lives better.”
Michael Fortier, president of Mikrolar Inc. in Hampton, New Hampshire, sees numerous other research applications with robots.
“A few of the niftier applications might be simulating the lack of gravity in space for programming satellite repair at NASA, or simulating heavy equipment skidders (machines used in logging) in the Yukon, or simulating the motion of an antenna at the top of a mast for a ship in rough seas,” he says.
While serial-connected, arm-shaped robots are common in manufacturing processes, Mikrolar’s devices look more like coffee tables. The company uses a parallel design whereby multiple legs work together to move a platform on top of the machine. Parallel robots are better suited than serial robots for intense physical tests, the company says.
“Conventional serial robots do not have good stiffness characteristics,” the company says on its website. “Serial robots have all of their connections in a row like your extended arm. A parallel mechanism has six linkages all interconnected for greater rigidity and stiffness.”
Robots reveal effects of therapies
Dr. Greg Kawchuk, DC, works with a robot to investigate how spines move and muscles act. In 2010, Kawchuk and other researchers published the first study to pinpoint the degree to which manual therapy affects tissues. Working with pig cadavers, the researchers applied manual therapy to the third lumbar vertebra and recorded the kinematic response there and in the fourth lumbar vertebra. Then the researchers used a robot to reproduce kinematic response so they could gauge the effects more accurately. They found that manual therapy affects certain tissues to a greater magnitude than others. As a result, Kawchuk and his team are investigating how DCs can target, or avoid, specific spinal tissues.
|Dr. Greg Kawchuk of the University of Alberta blends chiropractic and biomechanics through his research.|
To learn more, read, Identification of spinal tissues loaded by manual therapy: a robot-based serial dissection technique applied in porcine motion segments, published in Spine (volume 35, issue 22).
Also in 2010, Kawchuk and other researchers investigated the effectiveness of lumbar braces, which are often prescribed for disabilities caused by lower back pain. In this study, the researchers had brace-wearing and non-brace-wearing subjects sit on the robot, which tilted and turned. The researchers recorded the participants’ muscle activity. Kawchuk and his team discovered that although the braces suppressed some muscle movement, activity in different muscles can also increase. This paradoxical response helps explain why short-term use of braces does not appear to create atrophy.
To learn more, read, The application of parallel robotics to investigate the effect of lumbar bracing on trunk muscle activity, published in Applied Bionics and Biomechanics (volume 7, issue 4).
Stefan Dubowski is a freelance writer based in Ottawa. You can reach him at email@example.com.