Carrie Peterson, Ph.D., an assistant professor in the Department of Biomedical Engineering in VCU’s College of Engineering, is researching how to improve health and quality of life for individuals with spinal cord injury who use manual wheelchairs — from childhood through adulthood.

Peterson is providing expertise in simulation analyses as part of a team that has received a $2.5 million grant from the Eunice Kennedy Shriver National Institute of Child Health and Human Development at the National Institutes of Health. The lead principal investigator of the four-year study, aimed at disease prevention for individuals with spinal cord injury through the use of advanced biomechanical modeling and diagnostic imaging, is Brooke Slavens, Ph.D., associate professor in the College of Health Sciences at the University of Wisconsin-Milwaukee.

Individuals with spinal cord injury and resulting lower limb paralysis can retain some independence by using manual wheelchairs, but up to 84 percent of patients who use them develop shoulder pain associated with overuse injuries. “The benefit of a manual wheelchair is that it continues to give that person some degree of exercise,” Peterson said. “Ideally, we can develop strategies to keep people using manual wheelchairs in a manner that doesn’t create shoulder pain.”

Researchers have discovered a difference between adults who experience a spinal cord injury as children and begin using manual wheelchairs earlier in their lives compared to adults who have spinal cord injury as adults. Despite more years of wheelchair use, adults with pediatric onset actually have less shoulder pain. Children with spinal cord injury also have less pain and more variety in movement than adults, she said.

The reason for this difference is not understood. Variability of propulsion stroke patterns and joint dynamics may play a key role. This study will investigate, for the first time, the relationship between manual wheelchair propulsion by individuals with pediatric-onset and adult-onset spinal cord injury and the association with shoulder pain and pathology. Also, while there are clinical guidelines for wheelchair use to preserve arm function for adults, none exist for children.

For the study, Shriners Hospitals for Children-Chicago, Medical College of Wisconsin, Clement J. Zablocki VA Medical Center and Northwestern University will gather biomechanical data.

Peterson, who will receive $413,544 under the grant, will generate computational simulations of musculoskeletal dynamics during wheelchair propulsion to quantify shoulder joint contact forces. “The goal of the project is to determine whether the movement variability reduces the shoulder joint demands, and therefore leads to decreased shoulder pain and progressive pathology,” she said.

The long-term goal is to develop innovative rehabilitation strategies to prevent and treat symptoms of shoulder loading and overuse contributing to shoulder pain by creating guidelines for children and improving those for adults.

The problem with the secondary medical condition of shoulder pain is critical for individuals with spinal cord injury, Peterson said, “because pain leads to the loss of their ability to use their arms — which they rely on for mobility and independence.”