title: Temporal-spatial parameters of the upper limb during a Reach & Grasp Cycle for children.
abstract: The objective of this study was to characterize normal temporal-spatial patterns during the Reach & Grasp Cycle and to identify upper limb motor deficits in children with cerebral palsy (CP). The Reach & Grasp Cycle encompasses six sequential tasks: reach, grasp cylinder, transport to self (T(1)), transport back to table (T(2)), release cylinder, and return to initial position. Three-dimensional motion data were recorded from 25 typically developing children (11 males, 14 females; ages 5-18 years) and 12 children with hemiplegic CP (2 males, 10 females; ages 5-17 years). Within-day and between-day coefficients of variation for the control group ranged from 0 to 0.19, indicating good repeatability of all parameters. The mean duration of the Cycle for children with CP was nearly twice as long as controls, 9.5±4.3s versus 5.1±1.2s (U=37.0, P=.002), partly due to prolonged grasp and release durations. Peak hand velocity occurred at approximately 40% of each phase and was greater during the transport (T(1), T(2)) than non-transport phases (reach, return) in controls (P<.001). Index of curvature was lower during transport versus non-transport phases for all children. Children with CP demonstrated an increased index of curvature during reach (U=46.0, P=.0074) and an increased total number of movement units (U=16.5, P<.0001) compared to controls, indicating less efficient and less smooth movements. Total duration of the Reach & Grasp Cycle (rho=.957, P<.0001), index of curvature during reach and T(1) (rho=.873, P=.0002 and rho=.778, P=.0028), and total number of movement units (rho=.907, P<.0001) correlated strongly with MACS score. The consistent normative data and the substantial differences between children with CP and controls reflect utility of the Reach & Grasp Cycle for quantitative evaluation of upper limb motor deficits.
authors.affiliation: Department of Bioengineering, Stanford University, CA, USA. erine@stanford.edu
authors.forename: Erin E
authors.initials: EE
authors.lastname: Butler
authors.forename: Amy L
authors.initials: AL
authors.lastname: Ladd
authors.forename: Lauren E
authors.initials: LE
authors.lastname: Lamont
authors.forename: Jessica
authors.initials: J
authors.lastname: Rose
mesh_terms: D000293:Adolescent; D016022:Case-Control Studies; D002547:Cerebral Palsy / Q000503:physiopathology*; D002648:Child; D002657:Child Development / Q000502:physiology; D002675:Child, Preschool; D002658:Developmental Disabilities / Q000503:physiopathology*; D005260:Female; D018737:Hand Strength / Q000502:physiology*; D006429:Hemiplegia / Q000503:physiopathology; D006801:Humans; D008297:Male; D008959:Models, Neurological; D009068:Movement / Q000502:physiology; D011379:Prognosis; D011597:Psychomotor Performance / Q000502:physiology*; D012016:Reference Values; D015203:Reproducibility of Results; D018570:Risk Assessment; D013028:Space Perception / Q000502:physiology; D018709:Statistics, Nonparametric; D013997:Time Factors; D034941:Upper Extremity / Q000502:physiology