title: The arm posture in children with unilateral Cerebral Palsy is mainly related to antero-posterior gait instability.
abstract: In this observational case-control study we aimed to determine whether altered arm postures in children with unilateral CP (uniCP) are related to gait instability in a specific direction. Antero-posterior and medio-lateral Foot Placement Estimator instability measures and arm posture measures (vertical and antero-posterior hand position, sagittal and frontal upper arm elevation angle) were determined in eleven uniCP (7 years-10 months) and twenty-four typically developing children (9 years-6 months) at two walking speeds. Spearman-rank correlation analyses were made to examine the relationship between antero-posterior and medio-lateral arm posture and gait instability. Arm posture in both planes was related to antero-posterior instability (e.g. sagittal and frontal upper arm elevation angle correlated moderately with antero-posterior instability; R=0.41, p<0.001, R=-0.47, p<0.001). In uniCP, increased antero-posterior instability was associated with a higher (R=-0.62, p=0.002) and more frontal position of the hemiplegic hand (R=-0.58, p=0.005), while the non-hemiplegic upper arm was rotated more backward (R=0.63, p=0.002) and both upper arms rotated more sideways (hemiplegic: R=-0.58, p=0.004; non-hemiplegic: R=-0.55, p=0.008). The altered non-hemiplegic (sagittal and frontal) arm posture in uniCP may be a compensation to reduce antero-posterior gait instability.
authors.affiliation: Department of Rehabilitation Medicine, MOVE Research Institute Amsterdam, VU University Medical Center, Amsterdam, The Netherlands; Department of Kinesiology, Faculty of Kinesiology and Rehabilitation Sciences, KU Leuven, Heverlee, Belgium. Electronic address: pieter.meyns@gmail.com.
authors.forename: Pieter
authors.initials: P
authors.lastname: Meyns
authors.affiliation: Department of Kinesiology, Faculty of Kinesiology and Rehabilitation Sciences, KU Leuven, Heverlee, Belgium; Department of Research, Development and Education, Sint Maartenskliniek, Nijmegen, The Netherlands.
authors.forename: Jacques
authors.initials: J
authors.lastname: Duysens
authors.affiliation: Department of Rehabilitation Sciences, Faculty of Kinesiology and Rehabilitation Sciences, KU Leuven, Heverlee, Belgium; Clinical Motion Analysis Laboratory, CERM, University Hospital Leuven, Leuven, Belgium.
authors.forename: Kaat
authors.initials: K
authors.lastname: Desloovere
mesh_terms: D001132:Arm / Q000503:physiopathology*; D016022:Case-Control Studies; D002547:Cerebral Palsy / Q000150:complications / Q000503:physiopathology*; D002648:Child; D005260:Female; D005500:Follow-Up Studies; D005528:Foot; D005684:Gait / Q000502:physiology*; D020233:Gait Disorders, Neurologic / Q000209:etiology / Q000503:physiopathology*; D006801:Humans; D008297:Male; D011187:Posture / Q000502:physiology*; D016138:Walking / Q000502:physiology*
keywords: Arm posture; Cerebral Palsy; Foot placement estimator; Gait instability; Guard position