Andrea Utley

INTERLIMB COUPLING IN CHILDREN WITH HEMIPLEGIC CEREBRAL PALSY

Children with hemiplegic cerebral palsy participated in three experiments designed to examine interlimb coupling during reaching and pointing/grasping tasks. Comparisons were made between the hands working in isolation and working together. Descriptions of the movements involved both qualitative and quantitative methods, using normal video analysis and kinematic analysis. In order to obtain a total picture of reaching and grasping it was necessary to examine multiple variables both qualitatively and quantitatively. There was strong evidence of coupling between the hands, with coupling of timing being the most prevalent followed by coupling of trajectory and hand posture. All children showed some form of coupling in the experiments.

Ball catching in children with developmental coordination disorder: control of degrees of freedom

This study investigated two‐handed catching in eight children (four males, four females) aged 7 to 8 years (mean 7y 4mo [SD 3mo]) with developmental coordination disorder (DCD) and their age‐matched controls (AMCs). Kinematic data were collected to examine Bernsteins (1967) notion of freezing and releasing degrees of freedom (DF). Participants were asked to catch a ball 30 times, delivered in three blocks of 10 trials. Video analysis showed that children with DCD caught significantly fewer balls than their AMCs (p≤0.001) counterparts. Kinematic analyses showed that children with DCD exhibited smaller ranges of motion and less variable angular excursions of the elbow joints than their AMCs, and that their elbows are more rigidly coupled (p≤0.001). These data suggest that children with DCD rigidly fix and couple their limbs to reduce the number of DF actively involved in the task.

Movement rehabilitation after spinal cord injuries: Emerging concepts and future directions

Considerable inroads are being made into developing new treatments for spinal cord injury (SCI) which aim to facilitate functional recovery, including locomotion. Research on rehabilitative strategies following SCI using animal models has demonstrated that regaining and maintaining motor function, such as standing or stepping, is governed by principles of skill acquisition. Mechanisms key to learning motor tasks, including retention and transfer of skill, feedback and conditions of practice, all have examples in the SCI animal literature, although the importance of many concepts may often be overlooked. Combinatorial strategies which include physical rehabilitation are beginning to yield promising results. However, the effects of molecular-cellular interventions including chondroitinaseABC, anti-NogoA, foetal stem cell transplantation, etc., are still poorly understood with reference to the changes made to spinal plasticity by training and exercise. Studies that investigate the interplay between rehabilitation and other treatments have had mixed results; it appears likely that precise timings of different interventions will help to maximize recovery of function. Understanding how the time-course of injury and different rehabilitative and treatment modalities might factor into spinal plasticity will be critical in future therapeutic interventions.

The influence of object size on discrete bimanual co-ordination in children with hemiplegic cerebral palsy.

Purpose: To examine the influence of perturbation of object size on the nature and extent of interlimb coupling in children with hemiplegic cerebral palsy. Method: Participants completed a number of trials reaching and grasping unimanually and bimanually to a small cube (1.5 cm) and a large cube (6 cm). Both 3D kinematic data and video data were gathered and qualitative descriptions of the video data were made. Results: It was found that object size did influence the nature and extent of bimanual coupling. As in previous studies this varied from participant to participant and either or a combination of temporal, spatial, or postural coupling was observed. In some cases the hemiplegic hand was influenced by the non hemiplegic hand, while in others it was the reverse. Conclusions: The influence of context and the individual nature of children with cerebral palsy observed in this paper must be considered by those in rehabilitation. Additionally, the therapist might be able to use the natural tendency to couple to assist the functional control of the hemiplegic side.

Climbing towards recovery: investigating physically injured combat veterans' psychosocial response to scaling Mt. Kilimanjaro.

Purpose: To explore physically injured combat veterans’ psychosocial response to scaling Mt. Kilimanjaro. Method: Participants (n = 4) were male and ranged in age from 22 to 44 years. They had all been wounded as a result of active duty in Afghanistan between 15 and 42 months (M = 27.25) before the study. Data were collected throughout a 9-day climb on Mt. Kilimanjaro using multiple sources of ethnographic data collection techniques including semi-structured interviews and detailed observations. Data were analyzed using cross case analysis. Results: The findings are divided into themes that were drawn out of the data to illustrate the participants’ psychosocial response to their experience of climbing on Mt. Kilimanjaro. Key themes of self-determination, active coping and social support were identified from the data. Conclusion: Support for those in recovery from trauma should foster psychosocial resources needed for healthy functioning. Future research should explore the role of meaningful and challenging activities as a way of improving the experience of recovery following serious injury. Implications for Rehabilitation Injured combat veterans Acquiring an injury may result in physical disability, pain, physical limitations, stress and vulnerability, and loss of family and friends thereby hindering veterans’ capacity to recover. In a relatively small sample, this study shows that pursuing meaningful and challenging activities such as scaling Mt. Kilimanjaro may complement rehabilitation strategies. Services and support for those in recovery from trauma should foster psychosocial resources needed for healthy functioning.

Developmental sequences of two-handed catching: How do children with and without developmental coordination disorder differ?

The present study examined the movement patterns in children with developmental coordination disorder (DCD) and their age-matched controls (AMC) while catching two-handed. First, a cross-sectional study was conducted to investigate developmental characteristics within the three body component actions (arm, hand, and body) of two-handed catching hypothesized by Haywood and Getchell (). Data analyzed from 36 children (18 DCD, 18 AMC) aged 7–10 years who caught a ball 10 times, two-handed, showed that hypothesized sequences for the arm, hand, and body met the prelongitudinal screening criteria proposed by Roberton (), Langendorfer (), and Roberton, Williams, and Langendorfer (). In light of this, the second part of the study used these sequences to evaluate the movement patterns of 10 children with and 10 without DCD, aged 7–8 years. The data revealed that children with DCD displayed less advanced modal developmental sequence levels than AMC children with respect to the arm and body action components. (p ≤ 0.01) Children with DCD also exhibited less advanced developmental profiles than the AMC children (p ≤ 0.05), the group modal profiles being A2-H2-B2 and A3-H3-B3, respectively. These data also show that each child with DCD exhibited more developmental profiles over the 30 trials than the AMC children (p ≤ 0.01) and that each DCD childs modal developmental profile was unstable (Roberton, ). Thus, over trials children with DCD link together different action patterns of the arm, hand, and body, suggesting that they have not yet developed a stable pattern of coordination to satisfy the task constraints.

Children with movement difficulties.

The range, nature and extent of movement difficulties experienced by children and adults are extremely varied. Every year a number of children are born with a range of movement difficulties. These difficulties have a varying impact on the child’s functional and social independence, ranging from mild to severe. In some cases the child has an identifiable medical or neurological condition such as Cerebral palsy, Down syndrome, or Spina Bifida. Other children have a movement difficulty where there is no obvious medical condition or identifiable neurological disease. One example of this is children with Developmental Coordination Disorder (DCD), who experience movement coordination problems that are out of proportion with their general development [1]. Children may therefore have a specific or a general movement difficulty that influences their control and coordination in a variety of ways. Movement skills are important in daily life, and movement problems may have consequences in areas such as academic performance, self-confidence and social skills [2]. It is vital that each child receives the appropriate rehabilitation, home, and educational support to ensure full social and functional independence. By identifying the underlying causes of movement difficulties we are better able to plan intervention. Educationalists, health professionals, and researchers must work together to share good practice while ensuring that our knowledge of underlying principles of movement control grows and informs our daily practice. It is imperative that rehabilitation is based on sound theoretical foundations and that practising therapists are fully involved in the research process. It is also vital that researchers and practitioners work together to gain an understanding of the mechanisms and processes that mediate adaptive movement control. Therefore for each child we must ensure that we investigate the cause and the coping strategy employed and then use this information to plan intervention. The specific aim of this special edition was to present a range of papers from a variety of perspectives, with the focus on children with movement difficulties. The eight articles that constitute this special edition vary from those providing an overview of the area, to those looking at general aspects of movement control such as function and attention, and finally to those examining specific tasks such as catching. A variety of experimental studies employing a range of methodologies are included, with authors from varying backgrounds and institutions represented. The first paper by Sugden and Dunford presents a framework for examining different approaches to intervention in children with movement difficulties. This paper makes strong links between theory, experimental evidence, and intervention. The second paper (Steenbergen et al.) complements this work and combines both theory and experimental evidence with the emphasis on motor planning in hemiplegic cerebral palsy. The next three papers consider fundamental aspects of control. The first paper (Volman et al.) examines the relationship between motor ability, performance mental ability, and functional status in children with Down syndrome. This is followed by two papers looking at how children with Developmental Coordination Disorder are firstly able to accurately judge the limits of their action capabilities (Johnson & Wade), and the second paper which examines the allocation of attention and its influence on the integration of the visuo-spatial and motor systems. The final three papers examine how differing perturbations such as speed, and orientation influence motor output in children with Cerebral Palsy and DCD. The first (Astill) examines catching in children with DCD and considers if and how they are able to adapt to changing task constraints. The second (Ricken et al.) examines the coordination of reaching and walking when children with cerebral palsy have to intercept an approaching object. The final paper (Utley et al.) considers how bimanual coupling is influenced by perturbing the working surface during a reaching and grasping task in children with cerebral palsy. All of these papers add to our knowledge of the underlying deficit in children with movement difficulties and such information should form the foundations of any planned intervention or educational program. Each paper considers the implications for rehabilitation and I am sure that all professionals involved with individuals with movement difficulties Disability and Rehabilitation, January 2007; 29(1): 1 – 2

Coupling of the Reach and Grasp Phase During Catching in Children With Developmental Coordination Disorder

The authors studied 2-handed catching behavior in 10 children with developmental coordination disorder (DCD), aged 7-10 years old, and their typically developing peers (TDC). Participants performed 15 catches, and the authors examined kinematics of both transport and grasp phases. In terms of the transport phase, movement initiation and movement time was longer and peak deceleration was earlier in children with DCD. In addition, such children initiated the grasp phase earlier, and their maximal grasp aperture was larger. In children with DCD, the time to maximal grasp aperture was more variable, and that aperture was earlier when the authors examined it with respect to the transport phase of the catch. The data suggest that children with DCD may use a decomposition strategy to simplify the movement control of the transport and grasp phases of a catch.

Motor Control, Learning and Development

INTRODUCTION The aim of this book is to provide a resource for undergraduates on sport and exercise science degrees that would also be useful to individuals taking sports coaching courses or training to be physical education teachers or physiotherapists. It is part of the Instant Notes Series and “provides an overview of the key theories, definitions, and measurements of motor control, leading to a discussion on how the human body learns to control movement and the development of motor skills” (back cover). The first author is Director of the Centre for Sport and Exercise Sciences at the University of Leeds, UK and her co-author and former student Sarah Astill is in the School of Health Professions and Rehabilitation Sciences at the University of Southampton, UK.A. What is Motor Control? B. Classification of Skill C. Measurement in Motor Control D. Theories of Control E. Information Processing F. The Central Nervous System (Neurological Issues) G. Sensory Contributions to Control H. Theories of Motor Learning I. Stages of Motor Learning J. Memory K. Implications for Practice L. The Role and Function of Feedback M. Theories of Motor Development N. Development of Fundamental Movement Skills

The influence of perturbing the working surface during reaching and grasping in children with hemiplegic cerebral palsy

Purpose. To examine unimanual and bimanual reaching and grasping in children with hemiplegic cerebral palsy with particular emphasis on the nature and extent of interlimb coupling when the working surface is perturbed. Method. Nine children with hemiplegic cerebral palsy and 7 control children with no movement difficulties took part in the study. Children were asked to pick up a cube unimamually and bimanually when the surface it was placed on was either sloping away from the child (Experiment 1) or towards the child (Experiment 2). Both 3D kinematic data and video data were gathered and qualitative descriptions of video data were made. Results. The working surface did indeed influence the nature and extent of interlimb coupling and this varied from participant to participant. Analysis of the displacement data revealed that during the bimanual condition lower trajectories were produced by both the hemiplegic and non hemiplegic sides, especially in Experiment 2. The control group showed little difference between the unimanual and bimanual condition. Conclusions. Evidence of interlimb coupling is found, these studies support the findings of our previous work that indicates that there are some benefits to performing bimanual movements in children with hemiplegic cerebral palsy.