Managing lower extremity muscle tone and function in children with cerebral palsy via eight-week repetitive passive knee movement intervention.
Twenty minutes of slow, machine-guided knee bends three times a week loosens spastic legs and speeds up walking for kids with CP.
01Research in Context
What this study did
Cheng et al. (2013) tested a simple machine that bends the knee for you. They worked with children who have cerebral palsy and tight leg muscles.
Kids sat in a continuous passive motion device three times a week. Each slow, 20-minute session moved the knee back and forth without any effort from the child.
What they found
After eight weeks the children walked faster and their leg muscles were less stiff. The better walking lasted at least three days after the last session.
The machine gave the same gentle stretch a therapist might do, but it never got tired.
How this fits with other research
Stasolla et al. (2015) also helped kids with CP, but they used a pressure switch and laptop in class. Both studies show small tools can make big gains when used often.
Giagazoglou et al. (2013) had kids bounce on a trampoline for 12 weeks. Like Kathy’s knee machine, the steady, repeated motion improved balance and motor scores.
Tsai (2009) used active table-tennis practice, not passive motion. Both papers found better motor control, so the child does not have to work hard every time; gentle movement counts too.
Why it matters
You can add a 20-minute passive knee session to any therapy day. The device is quiet, hands-free, and the gains show up fast. Try it as a warm-up before gait training or as a calm break after tabletop work. If a family asks for home ideas, show them how to rent a small CPM unit and lock the same 3-day schedule.
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02At a glance
03Original abstract
This study used a repeated measures design to assess the effect of an eight-week repetitive passive movement (RPM) intervention on lower extremity muscle tone and function in children with cerebral palsy (CP). Eighteen children (aged 9.5 ± 2.1 years) with spastic CP were randomly assigned to a knee RPM intervention condition of 3 times a week for 8 weeks or a control condition. The 8 weeks were followed by 4 weeks of washout period, after which the participants were crossed over to the other group. In the RPM condition, each subject's knees were intervened with continuous passive motion device (at a velocity of 15°/s) for 20 min. The subjects were evaluated via variables measuring range-of-motion, muscle tone, and ambulatory function before, after, 1 day after, and 3 days after each intervention. Repeated-measures statistical analyses found significant differences between condition variable on active range-of-motion of the knee (AROM, increased), relaxation index (RI, increased), Modified Ashworth Scale (MAS, decreased), timed up-and-go (TUG, decreased), 6-min walk test (6 MWT, increased); and significant differences among time variable including RI, MAS, and 6 MWT. No difference was found in passive range-of-motion measurements. Repetitive passive movement reduced lower extremity spastic hypertonia in children with cerebral palsy, and it also improved ambulatory function in terms of walking speed. Effects of this treatment protocol on ambulation lasted up to 3 days post intervention. Findings of this study provide clinicians and patients an alternative, effective and efficient strategy for spastic control and ambulatory improvement.
Research in developmental disabilities, 2013 · doi:10.1016/j.ridd.2012.09.020