Robotic device maps sense deficits in young stroke patients

Pioneering research could pave way for better therapies in treating cerebral palsy

CALGARY — Researchers in Calgary have laid the groundwork for developing new therapies for children with early brain injuries by using a robotic device to measure their proprioception, or position sense.

That’s the unconscious perception of where the body is while in motion or at rest; for instance, closing your eyes and touching your nose requires position sense.

It’s believed this is the first time anyone has used the technology to study deficits in position sense in children who have had a perinatal stroke, which often results in cerebral palsy.

“Most of the research and therapeutic focus has targeted motor deficits in an effort to help children improve their physical abilities,” says Dr. Adam Kirton, an Alberta Health Services specialist in perinatal stroke and the senior researcher on the study.

“Measuring deficits in position sense will create a fuller picture of each patient’s condition. Armed with that information, it might be possible to develop personalized rehabilitation therapies that are more effective than what we have now,” says Kirton, who is an associate professor at the University of Calgary’s Cumming School of Medicine in the departments of pediatrics and clinical neurosciences, and a member of the Alberta Children’s Hospital Research Institute.

About 1,000 Alberta children are currently living with perinatal stroke. The perinatal period extends from the 20th week of gestation to shortly after birth. There are different types of perinatal stroke that cause different brain injuries. Cerebral palsy is often a secondary outcome that affects muscle movement and motor skills.

“Someone whose position sense has been affected might have difficulty knowing where their hand or arm is in space, adding to their difficulty in using their affected, weaker limb,” Dr. Kirton says. “We can try to make a hand stronger but, if your brain doesn’t know where the hand is, this may not translate into meaningful function in daily life.”

Andrea Kuczynski, a PhD candidate with the University of Calgary, has led the ongoing research using the KINARM (Kinesiological Instrument for Normal and Altered Reaching Movements) robotic device at the Foothills Medical Centre.

Kuczynski tested 40 children who had a perinatal stroke and compared their results with those of a healthy control group. Children sat in the KINARM with their arms supported by the exoskeleton, which measured movement as they played video games and completed various tasks.

All the children also underwent magnetic resonance imaging, which gave researchers detailed pictures of brain structure. This will allow the researchers to describe the differences in major sensory and motor tracks in the brain, and how this might relate to function.

“Without technology like this, it’s next to impossible to objectively measure position sense,” Kuczynski says. “In the future, the KINARM could be used as a tool for rehabilitation. Once we have an understanding of how an individual’s position sense has been affected, we can begin to focus and personalize rehabilitation.”

Adult studies in stroke survivors have shown that dysfunction in position sense can adversely affect safety, postural stability and motor function.

Max Challoner, a 12-year-old participant in the Calgary study, had a perinatal stroke that left him with mild physical impairments on his right side.

“He spent some time in an intensive care unit shortly after he was born because he was having seizures,” his mom Wendy Saunders says. “But once they were brought under control, his physical development was quite normal.”

Then, when he was in Grade 4, a teacher noticed he wasn’t doing so well. Subsequent testing led an occupational therapist to believe Max may have a sensory processing disorder, which may or may not be connected to the perinatal stroke.

“Getting involved in the research has helped us learn more about some of the issues surrounding perinatal stroke,” Wendy says. “The possibility that this could one day lead to tailored treatments for Max and other kids is quite exciting.”

The Hotchkiss Brain Institute’s Dr. Sean Dukelow and Jennifer Semrau, PhD, were also involved in the study, which was published in a recent edition of Neurorehabilitation and Neural Repair.

The project was funded by the Cerebral Palsy International Research Foundation, an Alberta Innovates – Health Solutions Graduate Studentship, and an Alberta Children’s Hospital CIHR (Canadian Institutes of Health Research) trainee studentship.

Alberta Health Services is the provincial health authority responsible for planning and delivering health supports and services for more than four million adults and children living in Alberta. Its mission is to provide a patient-focused, quality health system that is accessible and sustainable for all Albertans.

The University of Calgary is making tremendous progress on its journey to become one of Canada's top five research universities, where research and innovative teaching go hand in hand, and where we fully engage the communities we both serve and lead. This strategy is called Eyes High, inspired by the university's Gaelic motto, which translates as 'I will lift up my eyes.' Led by the Hotchkiss Brain Institute, Brain and Mental Health is one of six strategic research themes guiding the University of Calgary toward its Eyes High goals.

- 30 -