The "mirror box" illusion: effect of visual information on bimanual coordination in children with spastic hemiparetic cerebral palsy

The study examined symmetrical bimanual coordination of children with spastic hemiparetic cerebral palsy (SHCP) and a typically developing (TD) control group under conditions of visual feedback created by placing a glass screen, opaque screen or a mirror (“mirror box”) between the arms. The “mirror box” creates a visual illusion, which gives rise to a visual perception of a zero lag, symmetric movement between the two arms. Children with SHCP exhibited a similar mean coordination pattern as the TD control group, but had greater movement variability between the arms. Furthermore, movement variability in children with SHCP was significantly greater in the screen condition compared with the glass and mirror condition, which were similar to each other. The effects of the availability of visual feedback in individuals with hemiparesis are discussed with reference to central and peripheral mechanisms

Deliberately light interpersonal contact affects the control of head stability during walking in children and adolescents with cerebral palsy

Objective: To evaluate the potential of deliberately light interpersonal touch (IPT) for reducing excessive head and trunk sway during self-paced walking in children and adolescents with cerebral palsy (CP). Design: Quasi-experimental, proof-of-concept study with between-groups comparison. Setting: Ambulant care facility, community center. Participants: 26 individuals with CP (spastic and ataxic; GMFCS I-III; mean=9.8y; f=11, m=15) and in 39 typically developed (TD) children and adolescents (mean=10.0y; f=23, m=16). Interventions: IPT applied by a therapist to locations at the back and the head. Main Outcome Measures: As primary outcomes head and trunk sway during self-paced walking were assessed by inertial measurement units. Secondary outcomes were average step length and gait speed. Results: CP group: apex and occiput IPT reduced head velocity sway compared to thoracic IPT (both p=0.04) irrespective of individuals’ specific clinical symptoms. TD group: all testing conditions reduced head velocity sway compared to walking alone (all p≤0.03) as well as in apex and occiput IPT compared to paired walking (both p≤0.02). Conclusions: Deliberately light IPT at the apex of the head alters control of head sway in children and adolescents with CP. The effect of IPT varies as a function of contact location and acts differently in TD individuals

Changes in arm posture during the early aquisition of walking

Changes in arm posture and movement of the arms in relation to step width were studied longitudinally for 4 to 6 months in 6 infants who had just begun to walk. Arm postures and movements were coded from video recording and step width was calculated from force platform data. The results showed that arms were held in fixed postures during the first 10 weeks. A decrease in these fixed postures was correlated with a decrease in step width. The emergence of arm movement occurred when balance control improved. The hypothesis that arm postures fulfill the dual task of stabilizing the body in an upright posture while moving it forward is discussed. © 2000 Elsevier Science Inc. All rights reserved

Matching accuracy in hemiparetic cerebral palsy during unimanual and bimanual movements with (mirror) visual feedback

In the present study participants with Spastic Hemiparetic Cerebral Palsy (SHCP) were asked to match the position of a target either with the impaired arm only (unimanual condition) or with both arms at the same time (bimanual condition). The target was placed at 4 different locations scaled to the individual maximum reaching distance. To test the effect of mirror visual feedback of the less-impaired arm on the matching accuracy, an opaque screen or a mirror was placed in between the arms which masked vision of the impaired arm. Absolute endpoint error was smaller in the bimanual condition compared to the unimanual condition, but there was no effect of mirror visual feedback. Inspection of the individual data, however, showed that 13 out of 23 participants did experience a positive effect of mirror visual feedback. A positive correlation between the baseline error (screen) and the improvement in accuracy with mirror visual feedback seems to suggest that individuals with lower proprioceptive accuracy in the baseline condition may benefit more from mirror visual feedback. Together these findings indicate that bimanual therapy and therapy with mirror visual feedback might be valuable approaches for rehabilitation for a subset of the individuals with SHCP. © 2012 Elsevier Ltd

Persistent handwriting problems are hard to predict:A longitudinal study of the development of handwriting in primary school

Background: After one year of tuition, up to a third of primary school children show insufficient handwriting. It is unclear whether this early insufficient handwriting predicts persistent handwriting problems, because there is a dearth of studies that followed developmental trajectories longitudinally. Aims: To describe handwriting development in primary school children longitudinally and to determine predictive positive value and sensitivity of early handwriting assessment. To analyse whether underlying abilities helps early identification of persistent handwriting problems. Methods: 173 primary school children were yearly assessed for four years using the Concise Assessment Scale for Children's Handwriting and the Beery Buktenica developmental test of visual-motor integration. Results: Both quality and speed of handwriting increased with years of tuition, with a pronounced increase in quality between two and three years of writing tuition. Sensitivity and positive predictive value were low. The only significant predictor of handwriting quality was handwriting quality in the previous year. For handwriting speed, no significant developmental model was revealed. Conclusions: Quality and speed of handwriting after one year of tuition is not sufficiently predictive for distinguishing between transient insufficient handwriting and persistent handwriting problems three years later. Practitioners should hold back when referring children for remedial teaching

Patterns of postural sway in high anxious children

This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens

Comportamento dos parâmetros espaço-temporais de acordo com classificação de Ben Lomonding na marcha de crianças e adolescentes com paralisia cerebral / Behavior of spatiotemporal parameters according to Ben Lomonding classification in the march of children and adolescents with cerebral palsy

O estudo comparou as variáveis espaço-temporais da marcha de crianças e adolescentes com os níveis da classificação de Ben Lomonding (BL). Estudo transversal, realizado com 37 crianças e adolescentes com diagnóstico de Paralisia Cerebral, idades entre 5 e 16 anos e classificadas no nível I e II do GMFCS. A análise tridimensional de marcha seguiu protocolo do software Vicon Motus® 9.2. A comparação das médias dos subgrupos a partir da classificação BL foi realizada por Anova One way e Kruskal-Wallis. A estratificação da amostra ocorreu apenas do nível 0 ao 3 da BL, com o nível 2 apresentando maior representação 35,1% (n=13). Os parâmetros espaço-temporais diferiram em entre as subcategorias da BL para período do passo e pré balanço no membro inferior parético (MIP) e além destas variáveis houve no tempo de simples e duplo suporte no não parético (MINP). Sobre o padrão de assimetria de marcha observou-se significância na progressão de tronco durante o contato inicial, sendo maior no MINP seguindo os níveis da BL. A significativa relação espaço-temporais com os dados cinéticos seguindo a BL, propicia bases mais consolidadas das adaptações necessárias que o PC gera afim de manter a estabilidade e reorientar o corpo em cada fase de marcha

Children with cerebral palsy exhibit greater and more regular postural sway than typically developing children

Following recent advances in the analysis of centre-of-pressure (COP) recordings, we examined the structure of COP trajectories in ten children (nine in the analyses) with cerebral palsy (CP) and nine typically developing (TD) children while standing quietly with eyes open (EO) and eyes closed (EC) and with concurrent visual COP feedback (FB). In particular, we quantified COP trajectories in terms of both the amount and regularity of sway. We hypothesised that: (1) compared to TD children, CP children exhibit a greater amount of sway and more regular sway and (2) concurrent visual feedback (creating an external functional context for postural control, inducing a more external focus of attention) decreases both the amount of sway and sway regularity in TD and CP children alike, while closing the eyes has opposite effects. The data were largely in agreement with both hypotheses. Compared to TD children, the amount of sway tended to be larger in CP children, while sway was more regular. Furthermore, the presence of concurrent visual feedback resulted in less regular sway compared to the EO and EC conditions. This effect was less pronounced in the CP group where posturograms were most regular in the EO condition rather than in the EC condition, as in the control group. Nonetheless, we concluded that CP children might benefit from therapies involving postural tasks with an external functional context for postural control

Experimental neck muscle pain impairs standing balance in humans

Impaired postural control has been reported in patients with chronic neck pain of both traumatic and non-traumatic etiologies, but whether painful stimulation of neck muscle per se can affect balance control during quiet standing in humans remains unclear. The purpose of the present experiment was thus to investigate the effect of experimental neck muscle pain on standing balance in young healthy adults. To achieve this goal, 16 male university students were asked to stand upright as still as possible on a force platform with their eyes closed in two conditions of No pain and Pain of the neck muscles elicited by experimental painful electrical stimulation. Postural control and postural performance were assessed by the displacements of the center of foot pressure (CoP) and of the center of mass (CoM), respectively. The results showed increased CoP and CoM displacements variance, range, mean velocity, and mean and median frequencies in the Pain relative to the No pain condition. The present findings emphasize the destabilizing effect of experimental neck muscle pain per se, and more largely stress the importance of intact neck neuromuscular function on standing balance