Determining the most effective exercise for gluteal muscle activation in children with cerebral palsy using surface electromyography

Abstract

Background: Reduced lumbo-pelvic postural control is a common feature of gait in children with Cerebral Palsy (CP). These features are commonly attributed to insufficiency of the hip musculature as well as underlying bony geometry. Exercises aimed at strengthening the hip muscles are frequently prescribed in children with Cerebral Palsy (CP). There is a lack of evidence indicating the most effective exercises in targeting gluteal muscle activation in this population.

Research question: To determine the most effective exercise for gluteal muscle activation in children with CP.

Methods: This was a cross-sectional study of children with CP. Surface EMG data from the gluteus medius (GMed) and maximus (GMax) on the more involved limb were recorded as participants completed 6 commonly prescribed gluteal strengthening exercises. EMG was assessed for peak activation, normalised to functional reference values.

Results: Data from ten children (5 males, 5 females; mean +- SD age, 13+-3 years) were included for final analysis. The single leg bridge and step up were the most effective exercises for gluteal muscle activation. Differences in activation were found to be statistically significant using Friedman's rank test (GMax p = 0.0001, GMed p = 0.0023).

Significance: This study is the first to show clear differences in activation across gluteal strengthening exercises in a CP population. Exercises which involve weight bearing through a single limb appear most effective in activating the target muscles i.e the single leg bridge and the step up. Exercises involving double limb support or open-chain movements were less effective. The results of this study indicate that careful exercise selection is required to achieve targeted muscle activation in a paediatric CP population. The results of this study will provide guidance for exercise prescription for gluteal strengthening in this population and will inform future research studies on the effectiveness hip muscle strengthening programmes in CP.

Keywords: Cerebral palsy; EMG; Exercise prescription; Muscle activation; Strengthening.