Helping patients learn to walk again
Ross Querry researches how a treadmill system that supports body weight can help patients recover from spinal cord injuries.
A day among world-class doctors and rehabilitation specialists—developing cutting-edge technology and applying groundbreaking medical practices—is just another day on the job for alumnus Ross Querry.
The first University of Texas at Arlington graduate to receive a bachelor of science degree in exercise science, in 1995, Dr. Querry is an assistant professor in the Department of Physical Therapy at The University of Texas Southwestern Medical Center at Dallas.
“I knew I always wanted to have an impact on people’s lives, and this is a great opportunity to do that,” says Querry, who received his doctoral degree in biomedical science from the University of North Texas Health Science Center in Fort Worth in 1999. As a graduate student, he earned international research grants in 1998 and 1999.
He works collaboratively with seven doctors and physical therapists studying patients with spinal cord injuries. The interdisciplinary team is investigating how well a body-weight-supported treadmill system can retrain a patient’s body to walk.
“A spinal cord injury basically causes a break in your central nervous system,” Querry explained. “When an injury occurs, the brain and spinal cord may not communicate effectively with your arms or legs, thus inhibiting the control of activities such as walking.”
Techniques to regain ambulation after a spinal cord injury date back decades.
“The difference is, 20 years ago, if you were re-learning to walk, we would use bracing and crutches along with strengthening the muscles you had left. Basically, it was compensating for your deficits. Now we are adding the use of machines and technology to allow the neural circuits to re-learn how to control coordinated motion.”
Early methods of body-weight-supported treadmill rehabilitation involved manual work on a treadmill and therapists physically moving the patient’s legs in a walking motion. This was physically demanding on both the patients and the therapists.
Recent advances center around a computer-controlled ambulation assist device called Lokomat. Manufactured in Switzerland, UT Southwestern’s Lokomat system is one of only 10 in the United States.
“The Lokomat technology allows us to increase the direct ambulation training time, providing a unique and extremely repeatable walking pattern for patients,” said Querry, recently named a UT Arlington Distinguished Alumnus. “A robotic framework with motors attached to a patient’s legs provides the physical assistance to help the person with the walking motion. The repeatability that the Lokomat provides may be crucial in advancing the reorganization of the central nervous system to regain ambulation.”
UT Arlington’s Jim Hayes, head coach of the Movin’ Mavs wheelchair basketball team, suffered a spinal cord injury almost 40 years ago that left him paralyzed from the waist down.
“There have been many ideas put forth to help those with spinal cord injuries regain function,” he said. “While seemingly complicated in nature, sometimes the simple concept of movement in an upright position carries many peripheral benefits that add to longevity and quality of life.”
To investigate the impact on physiological mechanisms that may occur with Lokomat use, Querry’s team monitors brain activity.
“In healthy individuals, there are certain parts of the brain that are activated during walking,” he said. “People with spinal cord injuries have reduced activity in those parts of the brain, specifically the motor cortex and cerebellum, during attempted motor tasks. One of our questions is to find what areas of the brain change as an individual regains ambulation.”
The team utilizes brain-imaging devices such as magnetic resonance imaging and single-photon emission-computed tomography to create an image of brain activity of patients undergoing this therapy. Changes in muscle activation are analyzed using electromyography. The information obtained could be essential in helping the body walk again.
Querry, a member of the American Physical Therapy Association and the American Physiological Society, said that while robotics may be a prominent part of the rehabilitation process, the human mind and ingenuity still guide the research.
“It isn’t the robotic technology doing all of the work. Robotics is just another tool that allows patients the opportunity to train and potentially gain improved recovery.”
Despite early success stories, not every patient responds to body-weight-supported treadmill therapy. A successful outcome largely depends on the location of the patient’s injury and the time period in which rehabilitations begin. Eighteen to 24 months after an injury is the crucial period for rehabilitation.
Though still in its formative stages, the robotic body-weight-supported treadmill system offers a promising future.
“All the technological tools help doctors and therapists in their quest to better understand the mechanics of the body and its role in re-ambulation in patients,” Querry said. “I use my UT Arlington education every day to assist others with physical limitations. I wanted the opportunity to allow my research to further improve a patient’s quality of life. With the team’s work right now, we continue to strive for this step by step.”
— Jessica Pieczonka