title: Electromyographic investigation of extensor activity in cerebral-palsied children in different seating positions.
abstract: This study was designed to determine whether tonic myoelectric activity of low-back extensors of spastic cerebral-palsied children changed in response to changes in seating position, and if so, which position was coincident with the least extensor activity. Using two pairs of surface electrodes, the electrical activity of the lumbar erector spinae muscles was monitored in seven combinations of backrest inclinations (75 degrees, 90 degrees, 105 degrees and 120 degrees) and seat surface elevations (0 degrees and 15 degrees). Off-line analysis of action potential counts per second of recorded electromyographic signals showed that electrical activity was least when the seat surface elevation was 0 degrees and the backrest inclination 75 degrees. The results showed that differences existed in the activity of the low-back extensors in the seating positions that were assessed.
mesh_terms: D000200:Action Potentials; D000704:Analysis of Variance; D002547:Cerebral Palsy / Q000503:physiopathology* / Q000534:rehabilitation; D002648:Child; D002675:Child, Preschool; D004576:Electromyography; D005260:Female; D006801:Humans; D008297:Male; D009128:Muscle Spasticity; D011187:Posture