Dr. Dorothy Barthélemy, a leading researcher in spinal cord injury (SCI), is fascinated by why some people with SCI regain their ability to balance and walk over time – and others do not.
Based out of the Institut de réadaptation Gingras-Lindsay-de-Montréal and Hôpital du Sacré-coeur de Montreal (two of RHI’s Rick Hansen SCI registry sites), she conducts both clinical and laboratory experiments on the consequence of SCI on motor control and neural mechanisms of recovery. This provides her with a unique lens to view the impact of scientific research on the lives of patients.
Dr. Barthélemy started her career studying physical therapy and neuroanatomy, before moving into SCI research during her doctorate at Université de Montréal and a post-doctorate at the University of Copenhagen. She moved to Montreal in 2010.
Can you tell us about your research?
I am interested in “neuroplasticity” after an injury to the central nervous system, which is how the system reorganizes itself to regain function. This reorganisation can be positive and help recovery or it can bring about undesirable effects, like spasticity where certain muscles are continuously contracted.
There are two areas of neuroplasticity that I am currently investigating. The first involves identifying the neuronal pathways interrupted by a lesion. Our results indicate that lesions to specific pathways correlate to specific functional impairments. This knowledge can help clinicians develop treatment programs to boost neuronal function in pathways spared by the lesion and optimize recovery early after an injury.
The other area I am studying is decreased balance control in people with SCI. Even after intensive training programs (such as bodyweight-supported treadmill training), many individuals with SCI still do not acquire a functional walking pattern. This is largely due to poor balance control. To understand this better, we are examining the neurophysiological mechanisms and then proposing related training programs.
Can you describe your first experience working with someone with SCI?
When I was a physical therapy student, I worked with people with different neurological diseases, including patients with SCI, to optimize functional recovery. I was struck by the incredible difference in the function of body parts located above and below a SCI. For example, someone could have lost the ability to move their legs but could still have great arm strength. Therefore, even if a patient’s injury impacted their legs, a large part of the rehabilitation was to work on their arms, trunk and ability to transfer to chairs or the bedside so that they could have greater independence in everyday life.
Can you describe a time where you witnessed first-hand the impact of your research on a patient?
In one study we used MRI, electrophysiological and clinical methods to assess people with chronic incomplete SCI. At the end of the experiment, a few patients asked to see their own MRI images and electrophysiological data. After looking at the data, one of them began asking many questions. He wanted to better understand what was going on in his central nervous system. In all the years he had been injured, he did not have any information on the lesion itself. I think it gave him a sense of empowerment, if I can say that, because although he did not recover function after our study, he had a better understanding of what was going on and he could talk about it. Although the overall aim of our research is to improve function, increasing someone’s understanding of what is going on with their SCI is also beneficial.
Anything you have discovered through your research that has surprised you?
I have studied the central nervous system in healthy subjects as well as patients with different central nervous system diseases, including SCI and stroke. What surprises me the most is that even if the injury or way the lesion occurred is quite different, the impact to the central nervous system can be very similar. That’s because the pathways or structures are all interconnected. For example, a lesion to the motor cortex can lead to similar impairments as a SCI if the lesion interrupts the neuronal pathway between the motor cortex and the spinal cord. These interactions between different parts of the central nervous systems, and similarities across pathologies, are interesting to explore.
What has been the biggest challenge you have faced in your research?
The biggest challenge I have faced so far is translating the knowledge gained in the laboratory into the clinical rehabilitation setting. Our work aims to better understand the pathology, which in turn will lead to better and more objective assessments. However, the impact on the functional recovery of patients might not be readily obvious and might not seem relevant to everyday rehabilitation. This is unfortunate because these results bring about new concepts and may lead to new paradigms of treatment in the longer-term.
One way we are addressing this issue is by involving rehabilitation therapists at the onset of our research projects. This enables rich discussions that more clearly identify the problem we want to address and how the proposed solution could complement what is already being done in the clinic. This is likely to increase the chances that the clinic might take up a novel way of assessing or treating a problem.
What motivates you to continue studying SCI?
The progress made in the acute care of SCI in the past decades have been tremendous. More and more people survive a SCI, and for some, although they will remain with important incapacities, their life expectancy is similar to able-bodied individuals. We can improve their quality of life by improving sensorimotor recovery. To that end, understanding what is happening in neuronal networks above and below the lesion is essential. Looking at the scientific literature, it is clear that while a lot has been discovered in recent years, there is much more that remains unknown and is misunderstood. What motivates me to continue is that desire to contribute to improved functional recovery through my research on sensorimotor plasticity.