Spinal cord injury rehabilitation shouldn't be limited to training "working" body parts to compensate for body parts that have been paralyzed, despite a longstanding tradition of this approach. In her delivery of the 2014 John H.P. Maley Lecture, Andrea Behrman, PT, PhD, FAPTA, challenged her audience to look at spinal cord injury (SCI) through a "new lens"—one beyond a treatment plan based on the integrity of the descending connections between the brain and muscles below the injury as tested by the voluntary movement a person can generate below the lesion.
"We as physical therapists have a new lens with which to view paralysis—we can resolve paralysis," she said, arguing that we can raise the excitability of the spinal circuitry and activate the neuromuscular system below the level of injury after SCI. "Physical therapists can be agents for actual change in the capacity of the neuromuscular system after spinal cord injury," Behrman told the audience. Such advances in outcomes, she insisted, are in line with APTA's vision statement: "we can transform children [society] by optimizing movement—below and across the level of injury—to improve the human experience."
She recalled research by Reggie Edgerton as long ago as 1991, in which muscles below the level of injury in cats were activated to generate stepping, even responding to changing treadmill speeds.
"We learned from Edgerton and others that the spinal cord is, in fact, smart," Behrman said. More than just a conduit for neural messages, it synthesizes, integrates, and responds to input from descending neural pathways and ascending sensory pathways to generate motor output.
"Our view of SCI … depends upon the lens with which we view the neuromuscular system after injury," Behrman said. "If we look through the current lens, SCI disrupts descending neural pathways, and voluntary movements below the lesion predict outcomes, with no motor output. Paralysis cannot be resolved, there is no possibility beyond paralysis, and the answer to the problem of mobility is compensation."
She continued: "If we look through the new lens, SCI disrupts descending neural pathways, yet below the lesion a set of interneurons is preserved with the capacity to respond to activity-based, specific sensory input and generate a motor output."
Behrman described 3 training components to activate the neuromuscular system below the level of injury. First, the system is retrained in a controlled treadmill environment, providing task-specific cues such as load-bearing, limb and trunk position, and treadmill speed. Second, the treadmill skills are assessed and transferred to everyday activities. Third, new skills and abilities are integrated into the home and community.
Behrman provided examples from her Kids STEP Study, a clinical trial of locomotor training to restore walking in nonambulatory children with severe SCI. Out of 6 children, she said, 3 recovered stepping ability, and all 6 improved in trunk control with anecdotal reports from parents of improved sensation, recovery, or development of complete bowel and bladder control.
Based on the Kids STEP Study, activity-based locomotor training moved to an outpatient clinic for children with SCI. The parent of 1 child from the clinic provided the title for Behrman's presentation, "I Never Thought That I Would Need to Child-Proof My Home." The mother shared this thought as she watched her young daughter, who was paralyzed at the C6 level after an ischemic insult to her spinal cord when she was 3 months old, become so much more mobile in her home that her mother needed to act to protect her.
Do children have an advantage over adults in responding to activity-based therapies for SCI? Behrman believes so. Younger children, in particular, have greater plasticity than adults, and 1 result may be a tendency to respond more positively to activity-based therapies. She added that children also may benefit from their lack of cognitive understanding of their injury—adults attempt to resolve paralysis with cognitive effort, while children simply seek to play or move without giving a rationale or logic to their efforts. "We capitalize … on a child's innate desire to move, explore, and engage in their world to motivate and shape their therapeutic experience."
The 20th John H. P. Maley Lecture will be presented in 2015 during APTA's NEXT Conference and Exposition in National Harbor, Maryland, by Gad Alon, PT, PhD.