In her years of providing physical therapy to children with cerebral palsy (CP), Dr. Kristie Bjornson has faced a nagging problem. She can tell when her therapies – which include coaching children as they walk on a treadmill and supporting use of orthotics – make a patient’s gait better, improve their balance or help them walk faster in her clinic. But she never knows if this enables them to be more active in their real lives – to play T-ball, run with friends or engage in other normal childhood activities.
“Trying to figure out what happens when these kids go about their daily lives has always been like staring into a black box,” says Bjornson, a physical therapist at Seattle Children’s and a principal investigator in the Center for Child Health, Behavior and Development.
Now Bjornson is shedding light into that box, with some of the first research to investigate if common CP therapies make a difference in a child’s real-world activity levels.
Pinpointing When Orthotics Improve Activity
CP is a neurological disorder that can impair motor function and profoundly impact a child’s ability to walk. For decades, it has been standard practice to prescribe orthotics, which include foot and leg braces, to correct a child’s gait problems, physical differences or neurological tics. Bjornson recently completed a pilot study that was the first to examine whether orthotics allow children with CP to truly become more active.
The study enrolled 11 children with CP who wear “ankle foot orthotics” – braces that strap to the lower leg. Each participant was fitted with an accelerometer – a watch-like device that records things like how many steps its wearer takes and the intensity of their walking. Bjornson and her colleagues used the accelerometers to monitor participants’ activity levels over two 14-day periods. Participants wore their orthotics during one of the periods and went without them during the other period.
Bjornson’s team found that some orthotic prescriptions didn’t effectively address a child’s alignment problems. And some children actually walked less, and at a lower intensity, when wearing their orthotics.
Bjornson is using the pilot data to apply for a National Institutes of Health grant to do larger orthotics studies. This research could eventually help providers know which kids will benefit from orthotics, which kinds of orthotics work best for how a child walks and which kids will do better without them.
“We need to be smarter about when we prescribe orthotics,” Bjornson says. “If a family or their insurer is going to pay thousands of dollars for something like this, they should know it’s going to help them in day-to-day life.”
A New Approach to Treadmill Training
Bjornson is also studying a new approach to using treadmills to help children with CP. Treadmill training is an integral part of physical therapy for children with CP and other conditions that affect mobility. The standard treatment is to have a patient walk on a treadmill at the same rate for 30 minutes.
“That approach makes sense for adults because they tend to walk for longer durations,” Bjornson says. “But kids don’t move like adults – they tend to engage in short, intense bursts of physical activity.”
She is investigating whether incorporating interval training can improve how kids accelerate and sustain those short bursts. In a current pilot study, Bjornson has participants train on a treadmill five days a week for four weeks. During each 30-minute session, she has them walk at regular speed, accelerate to a higher speed for 30 seconds and then slow back down to their normal pace.
Three participants have completed the study. Each of them increased their overall stride rate and was able to spend more time moving at their fastest speed.
“Hopefully that carries over and makes it easier for them to play sports and just go out and be more like regular kids,” Bjornson says.
As with the orthotics study, Bjornson will use the data to apply for funding to test the intervention on a larger scale. That would mean teaming up with researchers around the country to access a larger population of children with CP. If they can prove the new approach works, it could be adopted by providers nationwide.
“I’m hoping we can improve therapy for a generation of kids with CP to allow them to go out and do what they want to do each day,” Bjornson says.