December 10, 2018 | Erin Bluvas, bluvase@sc.edu
Sheri Silfies, an associate professor who joined the exercise science department’s doctor of physical therapy (DPT) program this fall, and psychology associate professor Jennifer Vendemia are co-principal investigators on a nearly $1.6 million R01 grant from the National Institutes of Health. This project will enable the researchers to understand how changes in the brain may explain the development of movement limitations and persistent pain in individuals with lower back injuries.
“Despite a wide array of treatment options, the number of people who struggle to recover from painful back injuries continues to grow at an alarming rate,” says Silfies. “It is unknown why back pain remains so treatment resistant.”
To answer this question, Silfies and Vendemia have some ideas they’d like to explore. Based on findings from previous studies, the researchers believe that this type of back pain may be connected to a pattern of integration errors between sensory feedback and motor behavior. These errors trigger remodeling of the motor cortex, which controls voluntary movements.
Back injuries often lead to temporary adaptations in spinal movement and muscle activation patterns. The short-term effect of these adaptations helps protect injured tissues and avoid further pain, but these same protective measures can lead to maladaptive patterns during and following the recovery period of an acute back pain episode. These patterns result in a cycle of stress to spinal structures that can lead to recurrent and chronic lower back pain.
“We believe that these habitual, maladaptive movement patterns are driven, in large part, by changes in how the brain controls spine movement which in turn synergistically interacts with the behavioral, cognitive, and emotional aspects of the pain experience,” explains Silfies. “Our preliminary data suggests that individuals with chronic lower back pain synthesize sensory feedback differently and have altered relationships between sensory and motor regions of the brain during tasks that require movement and stabilization of the spine. These alterations complicate an individual’s ability to refine movements, thus making change in movement deployment and response to pain rehabilitation more difficult.”
With this new project, the researchers plan to collect additional evidence supporting this relationship between the brain and back pain. They also hope to gain a better understanding of the underlying mechanisms that support this relationship, paving the way for improved treatment options.
“I have always been fascinated by human anatomy and its role in how the body moves,” says Silfies, who first became interested in becoming a physical therapist when she was in high school. That interest became a passion during college when she began to understand the mechanisms underlying musculoskeletal injuries and how those injuries, along with pain, affect movement patterns and function.
The Pennsylvania native earned a bachelor’s degree in physical therapy at the University of Scranton before beginning her clinical career in 1987. Along the way, she completed a master of science in exercise physiology from the Indiana University of Pennsylvania and then a Ph.D. in rehabilitation sciences at MCP Hahnemann University. Following her 2002 Ph.D. graduation, Silfies joined the Yale University School of Medicine as a postdoctoral fellow in spine biomechanics and motor control.
“I became interested in understanding the mechanism underlying persistent lower back pain based on my clinical experiences with those struggling to regain or maintain function during episodes of recurrent and persistent back pain,” says Silfies. “The individuals with recurrent or persistent lower back pain seemed to be the most challenging to manage and this drove me to want to learn more about its causes and potential treatment approaches.”
Over the past 20 years, Silfies held academic appointments at two Pennsylvania-based universities before joining the University of South Carolina, where she had already been serving as an adjunct faculty member for the DPT program. The Arnold School’s exercise science department has a strong DPT program, which, for Silfies, provides an opportunity to foster in students a strong foundation in human anatomy, kinesiology and motor control. It also offered the infrastructure to effectively support her research interests and allow her to continue to train future rehabilitation researchers in the school’s Ph.D. in exercise program (Ranked No. 1 in the U.S. by the National Academy of Kinesiology).
“South Carolina moved to the top of the list based on my professional interactions with the current DPT faculty members and a developing collaboration with Drs. Paul Beattie, Jill Stewart, and Jennifer Vendemia,” says Silfies, who directs the Applied Neuromechanics Lab. “We had collaborated on several NIH grant applications over the past few years that drew interest and had gotten good feedback, and we just happened to get notification that an R01 application got funded within a month of my joining USC. This grant represents a true collaboration between professions that provides a unique opportunity to answer some questions about movement control and chronic pain in individuals with persistent lower back pain.”