Stance posture control in select groups of children with cerebral palsy: Deficits in sensory organization and muscular coordination

Abstract

This study has focused upon the automatic components of posture and movement in a group of ten cerebral palsy children carefully selected to represent a spectrum of abnormalities relatively pure by clinical standards and ten age-matched normals. Each subject stood unsupported upon a movable platform and within a movable visual surround and was then exposed to external perturbations or was asked to pull with one arm upon a movable handle. In comparing the performance of cerebral palsy children in each clinical category with the age-matched normals and with normal adults assessed in previous studies, the process of maintaining stance was subdivided into two component functions: substrates which determined the onset timing, direction and amplitude of postural actions from somatosensory, vestibular, and visual stimuli were termed "sensory organization", and those establishing temporal and spatial patterns of muscular contractions appropriate to produce effective movements were termed "muscle coordination". We found among seven of the ten cerebral palsy children a clear localization of dysfunction within either sensory organization or muscle coordination mechanisms. These results are providing some new insights into the organization of each of these processes as well as suggesting methods for developing a more systematic understanding of the abnormalities of movement control.

Deficits in anticipatory inhibition of postural muscle activity associated with load release while standing in individuals with spastic diplegic cerebral palsy

“…Many previous studies on CPAs to external perturbations (e.g., support surface translation) have revealed that a higher degree of antagonistic coactivation of ventral and dorsal postural muscles is a primary characteristic in individuals with SDCP (Burtner et al 1998;Nashner et al 1983;. In the present study, the percentages of trials with anticipatory antagonistic coactivation in the thigh and lower leg tended to be higher in the SDCP group than in the control group.…”

Effect of treadmill gait training on static and functional balance in children with cerebral palsy: a randomized controlled trial

“…Children with CP exhibit an increase in co-contractions of the proximal and distal muscles, with no coordinated proximal-distal pattern 26 . According to Nashner et al 27 , CP children present an inverse order of distal and proximal activation and muscle synergies, which compromises responses to disequilibrium. Findings described in the literature demonstrate that treadmill training provides improvements in gait velocity 17,19 , gross motor function 15,20 and the kinematic pattern of the lower limbs 20 .…”

The Reliability of the Star-Excursion Test in Assessing Dynamic Balance

“…Sports activities also require proper balance control. The visual, somatosensory, and vestibular systems all contribute to the maintenance of balance (10) and may be adversely affected by musculoskeletal injury, head trauma, disease, or aging. These influences on the visual, somatosensory, and vestibular systems might decrease a person's ability to perform dynamic activities and, thus, impede normal daily functioning (2,6,17,23).…”