March 3, 2014
Horton Hears A Who?
Some days I feel like Horton searching for Who-ville, trying to find clinically relevant information in a sea of lab-focused postural control research. However, like Horton, my perseverance has paid off and I have found some research highlights that have informed my clinical practice for children with disabilities.
Over the years we’ve confirmed that children with spastic CP do have decreased postural stability1. They display altered muscle activation patterns in the trunk and hip muscles and this may contribute to a decreased biomechanical efficiency2. Children with CP typically show a top-down recruitment order of muscles during postural perturbations (trunk to ankle), in contrast to typical children who display a bottom-up recruitment order (ankle to trunk)3. However, this top-down recruitment order may, at least partially, be a function of alignment4,5. This group of children have a poorer quality of anticipatory postural adjustments (greater variability and shorter amplitude of excursion)5,6 so not surprisingly, they use mostly compensatory strategies to maintain their postural control7 in sitting. Clinically this is also what I see for my clients in standing. In other words, they react to movement once it has begun better than they prepare for movement before it starts. However, altering their alignment has the potential to improve their preparation for movement and consequently, their stability and function4, 8,9
All of which leaves me feeling a little more optimistic in my search for Who-ville.
1. Donker SF, Ledebt A, Roerdink M, Savelsbergh GJP, Beek PJ. Children with cerebral palsy exhibit greater and more regular postural sway than typically developing children. Exp Brain Res. 2008; 184: 363-70.
2. Prosser LA, Lee SCK, Barbe MF, VanSant AF, Lauer RT. Trunk and hip muscle activity in early walkers with and without cerebral palsy – a frequency analysis. J Electromyogr Kinesiol. 2010; 20(5): 851-59.
3. van der Heide JC, Hadders-Algra M. Postural muscle dyscoordination in children with cerebral palsy. Neural Plast. 2005; 12(2-3): 197-203.
4. Burtner PA, Woollacott MH, Qualls C. Stance balance control with orthoses in a group of children with spastic cerebral palsy. Dev Med Child Neurol. 1999; 41: 748-57.
5. Girolami GL, Shiratori T, Aruin AS. Anticipatory postural adjustments in children with hemiplegia and diplegia. J Electromyogr Kinesiol. 2011; 21: 988-97.
6. Liu WL, Zaino A, McCoy SW. Anticipatory postural adjustments in children with cerebral palsy and children with typical development. Pediatr Phys Ther. 2007; 19: 188-95.
7. Bigongiari A, de Andrade e Souza F, Franciulli PM, El Razi Neto S, Araujo C, Mochizuki L. Anticipatory and compensatory postural adjustments in sitting in children with cerebral palsy. Hum Mov Sci. 2011; 30: 648-57.
8. Cherng RJ, Lin HC, Ju YH, Ho CS. Effect of seat surface inclination on postural stability and forward reaching efficiency in children with spastic cerebral palsy. Res Dev Disabil. 2009; 30(6): 1420-27.
9. Mannell S, Wiebe J. Evidence based core stability in children with challenges. Presented at APTA Combined Section Meeting; January 2013; San Diego, CA
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