Abstract Background Congenital hemiplegia is the most common form of cerebral palsy accounting for 1 in 1300 live births. Children usually present with greater upper limb than lower limb involvement. Impaired unimanual capacity of the involved upper limb and deficits in bimanual performance contribute to difficulties with day to day activities and participation in home, school and community life. Interventions to address these deficits in upper limb unimanual capacity and bimanual performance have recently shifted focus to address limitations in activity performance rather than underlying impairments. One intensive intervention approach is constraint induced movement therapy, which entails placing a constraint on the unimpaired upper limb to focus intense and repetitive training of the impaired upper limb. To date, it is unclear whether constraint induced movement therapy is superior to a more traditional bimanual therapy to improve activity performance and participation outcomes for children with congenital hemiplegia, as there has been no direct comparison of the two approaches. Aim The primary aim of this research was to determine whether constraint induced movement therapy was more effective than bimanual training to improve activity performance and participation for children with congenital hemiplegia. The specific aims were to: i) determine the efficacy of therapeutic upper limb interventions on activity and participation outcomes for children with congenital hemiplegia, ii) systematically review the clinimetric properties (psychometric properties and clinical utility) of participation assessment tools for children with congenital hemiplegia, iii) examine the relationship between impairments, unimanual capacity and bimanual performance in children with congenital hemiplegia and, iv) determine whether constraint induced movement therapy is more effective than bimanual training to improve activity and participation outcomes for children with congenital hemiplegia. Research Design A matched pairs randomised design was chosen with children matched for age, gender, side of hemiplegia and upper limb function. Children were randomised within pairs to receive either constraint induced movement therapy or bimanual training in equal dosages. Both interventions used a day camp model, with groups receiving the same dosage and content of intervention delivered in the same environment. A novel circus theme was used in the camps to enhance children’s engagement and motivation. Children in the constraint induced movement therapy group wore a tailor made glove on their unimpaired hand during the intervention camp. Outcomes were measured across all domains of the International Classification of Functioning, Disability and Health at baseline, 3 and 26 weeks post intervention. The primary outcome measure for unimanual capacity of the impaired upper limb was the Melbourne Assessment of Unilateral Upper Limb Function, and bimanual performance was the Assisting Hand Assessment. A secondary outcome measure for unimanual capacity was the Jebsen Taylor Test of Hand Function. The Canadian Occupational Performance Measure was used as the primary outcome for participation and three measures, the Assessment of Life Habits, Children’s Assessment of Participation and Enjoyment and the School Function Assessment were included to explore their research utility and responsiveness to change. Results Two systematic reviews were performed prior to the commencement of the randomised trial. The first systematic review and meta-analysis of all upper limb interventions for children with congenital hemiplegia identified four treatment approaches with varying evidence to support their efficacy. Interventions included the use of intramuscular Botulinum toxin A injections to the upper limb augmenting upper limb training, neurodevelopmental treatment, constraint induced movement therapy and hand arm intensive bimanual training. Data were pooled for upper limb, self care and individualised outcomes. Results indicated a small to medium treatment effect favouring all four interventions on upper limb outcomes. Large treatment effects favoured intramuscular Botulinum toxin A injections combined with upper limb training for individualised outcomes. Overall, the systematic review and meta-analysis found no upper limb training approach to be superior although Botulinum toxin A injections appeared to provide a consistent supplementary benefit to a variety of upper limb training approaches. However it was unclear which type of upper limb training was optimal. Findings suggested that the two intensive intervention approaches that are the focus of this randomised controlled trial, constraint induced movement therapy and bimanual intensive training, required further research to support their efficacy. The second systematic review was performed to inform choice of participation measures for the randomised comparison trial. The review identified five specific measures of participation suitable for school aged children with congenital hemiplegia (Assessment of Life Habits, Children’s Assessment of Participation and Enjoyment, School Function Assessment (participation domain), Children Helping Out: Responsibilities and Expectations, School Outcome Measure) and two measures of individualised outcomes that could include specific participation goals (Goal Attainment Scaling and Canadian Occupational Performance Measure). Results suggested that no one measure adequately captured all aspects of participation as outlined in the International Classification of Functioning, Disability and Health, and a combination of assessments would be required to broadly assess children’s participation in home, school and community life. The Canadian Occupational Performance Measure was selected as the primary outcome measure in the randomised trial as it had strong evidence for validity and reliability, had been used in paediatric clinical trials and was responsive to change. Three measures of participation, the Assessment of Life Habits which was completed by the parent/caregiver, the Children’s Assessment of Participation and Enjoyment which was completed by the child, and the School Function Assessment, which was completed by the child’s teacher, were selected to explore the research utility of the measures and their responsiveness to change. Analysis of cross-sectional data collected during screening and baseline assessments for the randomised trial found a strong relationship between bimanual performance and unimanual capacity. Scores on the Melbourne Assessment of Unilateral Upper Limb Function and stereognosis accounted for a significant amount of variance in scores on the Assisting Hand Assessment. There were only moderate associations between impairments (eg. sensory deficits and reduced grip strength) and bimanual performance and unimanual capacity. Age, gender, grip strength and two-point discrimination did not significantly influence bimanual performance. Results of the randomised controlled trial found no differences between groups on any baseline measure. A significant difference between groups favouring the constraint induced movement therapy group was found at 26 weeks on the Melbourne Assessment of Unilateral Upper Limb Function. There were no differences between groups on any other measure at either immediately post intervention at 3 weeks or in the medium term at 26 weeks. The constraint induced movement therapy group made significant gains in unimanual capacity (Melbourne Assessment of Unilateral Upper Limb Function and Jebsen Taylor Test of Hand Function) from baseline to 3 and 26 weeks. The bimanual group demonstrated significant improvement in movement efficiency (Jebsen Taylor Test of Hand Function) by 26 weeks. Significant gains in bimanual performance (Assisting Hand Assessment) were evidenced for both groups from baseline to 3 weeks. These gains were maintained at 26 weeks by the bimanual group only. There were no differences between groups on any participation measures. Both constraint induced movement therapy and bimanual training groups made statistically and clinically significant changes in perceived performance and satisfaction of identified functional goals from baseline to 3 and 26 weeks. Significant gains were made by both groups in personal care on the Assessment of Life Habits from baseline to 26 weeks. There were no changes for either group on the School Function Assessment and Children’s Assessment of Participation and Enjoyment. Conclusions This study found minimal differences between the two training approaches. Outcomes achieved by children reflected the mode of upper limb training, that is, improved and sustained gains in unimanual capacity were achieved with a unimanual approach (constraint induced movement therapy), and significant change in bimanual performance was achieved following bimanual training. The constraint induced movement therapy group made initial improvements in bimanual performance that were not sustained at 26 weeks, suggesting that intensive unimanual training may need to be followed by bimanual training in order to retain effects. Both interventions resulted in significant improvements in the achievement of individualised outcomes. Small gains in participation appeared to correspond with specific goal areas identified by children and their caregivers and highlighted the importance of goal directed training and measuring individualised outcomes. Regardless of the type of approach, intervention needs to be goal-directed, focusing on areas of central importance for children and their families.

The issue of the laterality of control during unimanual and bimanual coordination was addressed in this thesis. Two tasks were used throughout: a repetitive discrete response task (finger tapping) and a continuous task (circle-drawing). Different mechanisms have been implicated in the temporal control of repetitive discrete movements and continuous movements. The tasks also differ in the degree of spatiotemporal coordination required which might have important implications in the question of laterality of control. The first section of the thesis examined between-hand differences in the dynamics of performance during unimanual and bimanual coordination. During tapping, the dominant hand was faster and less temporally variable than the nondominant hand. During circle drawing the dominant hand was faster, more accurate, less temporally and spatially variable, and produced smoother trajectories than the nondominant hand. During bimanual coordination, several of these asymmetries were attenuated: the rate of movement of the two hands became equivalent (the hands became temporally coupled), the asymmetry in temporal variability during tapping was reduced, and the asymmetry in trajectory smoothness during circle drawing was reduced. The second section of the thesis examined the effects of disrupting motor processes with transcranial magnetic stimulation (TMS) over the left or right primary motor cortex (M1) on the ongoing performance of the hands. In the first study, TMS over left or right M1 during unimanual tapping caused large disruptions to tapping with the contralateral hand but had little effect on the ipsilateral hand. In contrast, for a subset of trials during bimanual tapping, two lateralized effects of stimulation were seen: the effect of TMS on the contralateral hand was greater after stimulation over left M1 than after stimulation over right M1, and prolonged changes in inter-tap interval were observed in the left hand regardless of the side of stimulation. In the second study, TMS over left M1 during circle drawing decreased the accuracy of drawing with both the contralateral and ipsilateral hand, whereas TMS over right M1 decreased accuracy of drawing only with the contralateral hand. This lateralized effect was not limited to the bimanual case, but was also apparent during unimanual drawing. The final chapter addressed issues in bimanual motor control after unilateral stroke. Performance of the affected limb was examined during unimanual and bimanual coordination in a group of stroke patients with varying levels of impairment. The results indicated an improvement in the performance of the affected limb for some patients with mild to moderate, but not severe upper limb motor deficits during bimanual movement. The improvements were limited to the patients who showed evidence of temporal coupling between the hands. These findings support the hypothesis that the dominant motor cortex has a role in the control of both hands during bimanual coordination. In addition, the dominant hemisphere appears to play a role in controlling both hands during unimanual movements which require a greater degree of spatiotemporal coordination. The final study suggests that temporal coupling between the limbs is crucial for the facilitation of performance of the affected limb during bimanual coordination, which has both theoretical and practical implications.

Made available in DSpace on 2014-06-11T19:22:51Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-04-13Bitstream added on 2014-06-13T20:49:24Z : No. of bitstreams: 1 alleoni_bn_me_rcla.pdf: 271182 bytes, checksum: 594a6de6d91f33e25e2fa9504c48d56b (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / A coordenação bimanual é um comportamento manifestado diariamente pelas pessoas na execução de tarefas do dia-a-dia. Controlar as duas mãos para varrer a casa, soltar pipa, costurar ou tocar piano são situações rotineiras que podem ser melhoradas e desempenhadas com precisão como resultado da prática. As tarefas unimanuais e as tarefas bimanuais que devem ser lideradas por uma das mãos, geralmente, são executadas apenas com a mão preferida, a mão direita para o maior número de pessoas. As ferramentas utilizadas nas tarefas do dia-a-dia são fabricadas para a mão direita e como conseqüência a diferença no desempenho é menor entre as mãos de pessoas com preferência manual esquerda. Manter um ritmo qualquer ou acertar alvos são tarefas que requeiram integridade de estruturas orgânicas, como por exemplo, os membros superiores e os sistemas visual e auditivo. O direcionamento da atenção visual pode ser muito importante na captura da informação para tocar alvos no plano horizontal, principalmente se as características espaciais e temporais das tarefas das duas mãos são diferentes. Contudo, as duas mãos estão separadas fisicamente e no desempenho em uma tarefa que requeira deslocamentos diferentes para as duas mãos o executante deve identificar a informação de uma das mãos para a execução precisa. O objetivo deste estudo foi verificar o efeito do direcionamento da atenção visual a uma das mãos no desempenho de uma tarefa bimanual com diferentes níveis de complexidade, em função da preferência manual. Pessoas com preferência manual direita e esquerda executaram uma tarefa de coordenação bimanual com deslocamentos dos membros superiores para o toque em um ou mais alvos que estavam igualmente distantes no plano horizontal e em intervalos temporais iguais ou diferentes. O direcionamento da atenção visual foi manipulado... / Bimanual coordination is a behavior showed by people during the performance of many daily tasks. Actions that require the control of the hands as to sweep the room, to free pipe, to sew or to play piano are very common actions that can be improved and performed with accuracy as a result of practice. The unimanual tasks and the bimanual tasks that must be led by one of the hands, in general, are performed by the preferred hand, the right hand for a large number of individuals. Tools used in daily tasks are tailored for right hand and as a consequence the difference in performance between hands is smaller for those left-handed. To keep moving in a rhythm or to reach targets are tasks that require a full functioning of organic structures as the upper limbs or visual and auditory systems. The direction of visual attention can be very important in capturing relevant information for touching targets in the horizontal plane mainly if the characteristics of tasks of the two hands are different. However, the hands are physically apart and in the performance of a task that requires different displacements for the two hands the performer must pick up information from one of the hands for performance accuracy. The objective of the present study was to verify the effect of directing visual attention to one of the hands in the performance of bimanual tasks with different levels of complexity as a function of hand preference. Right- and left-handers performed a bimanual coordination task with displacement of the upper arms to reach one or more targets that were equally distant in the horizontal plane and in equal or different temporal intervals. The direction of visual attention was manipulated in three experimental conditions, in a condition directed to the right hand, in another to the left hand and in a third condition of free choice of the performer. The variables selected... (Complete abstract click electronic access below)

Background: Bilateral training is an intervention used in patients with hemiparesis. This training is based on the movement of both (bi) sides (lateral) of the body simultaneously. There exist a lot of articles focused on specific methods of bilateral training. However, the used terminology is inconsistent. The aim of this thesis is to describe the neurophysiological background of bimanual and bilateral methods, review and clear out the used terminology, and describe the different techniques included in bilateral training. Methods: Relevant literature was searched in PubMed, ScienceDirect and OVID Evidence Based Reviews. The inclusion criteria were the availability of fulltext, publication date after 1980, English language and a connection with medicine. The searched keywords were bimanual or bilateral training, metod and therapy. Results: From 1021 articles, only 132 articles meet the inclusion criteria. Five main rehabilitation interventions are used in practice: a) cooperative activity of both arms, b) synchronous movement of both arms c) Mirror therapy, d) an activity, where the impaired hand assists the paretic hand and d) robotic therapy or therapy with mechanical devices. The neurophysiological background is based on a) modulation of interhemispherical inhibition, b) increased motor control of...

When exploring movement production, motor control researchers have been interested in investigating the relative contributions to different types of movement. In a research setting, a startling acoustic stimulus (SAS) can be used as a tool to explore the neural processes that are occurring when preparing and initiating a movement. Additionally, suprathreshold TMS is another tool which can induce a suppression of the cortical region of the brain, resulting in RT delays which provides us with the ability to assess the corticospinal contributions to a particular movement. The aim of the current study was to investigate potential differences in the planning and execution of bimanual versus unimanual wrist extension movements. It was of particular interest as to whether bimanual coupling occurs at the cortical level or in lower parts of the output pathway (reticulospinal). Participants (N=6) were instructed to complete a unimanual or bimanual wrist extension following a control go-signal or a SAS. For subset of trials, in order to explore the level of corticospinal excitability of the movement, suprathreshold TMS was applied over the left M1 during the task to induce a cortical silent period (CSP). Results revealed that theimpact of TMS on response initiation was not significantly different for unimanual task versus a bimanual task. Furthermore, the SP (silent period) only had an impact on the right limb and not the left during the bilateral task. Lastly, SAS did lead to shorter RTs for both the unimanual and bimanual wrist extension task, but the RT delay induced by TMS in the right limb was not shorter in SAS trials compared to control. The findings of the present study suggest that bimanual coupling may be occurring at the cortical level and in lower parts of the output pathway as there may be correlated neural activity in the two hemispheres occurring during bimanual wrist extension movements.

<p dir="ltr">Ninety percent of humans are right-handed, and this is often construed to mean that the right hand is better than the left at all tasks, in the right-handed individuals. However, we often ignore the important role played by the left-hand when performing certain bimanual tasks. For instance, when slicing a bread loaf, stabilizing the bread with the left hand is as important as slicing it with the right hand. This implies that each hand is dominant in different types of tasks. The influential dynamic dominance theory posits that each hand’s specific dominance arises from the contralateral hemisphere specialization. The dominant (right) arm produces well-coordinated movements because the left hemisphere is superior at predictive control, and the non-dominant (left) arm shows better stabilizing performance because the right hemisphere is superior at impedance control. This theory has been proposed by studying arm movements. However, it is unclear whether the features of this theory extend to grip force control during object manipulation. This is an important gap in our knowledge; identifying the differences in hand-specific control of grip force would improve our understanding of sensorimotor control of skilled bimanual manipulations. Therefore, the goal of my dissertation was to investigate whether the features of dynamic dominance extend to the control of grip forces in bimanual object manipulation.</p><p dir="ltr">In this dissertation, I performed two studies to investigate the control of complex, bimanual object manipulation tasks. Participants held an object in each hand. The two objects were connected by a spring. The grip forces of each hand accounted not only for the dynamics of the object that the hand manipulated, but also for the destabilizing forces that arose from the actions of the other hand that were transmitted by the spring. This experimental design mimics ecological tasks like slicing bread to the first degree of approximation. The goals were to determine whether the features of hand-specific specialization of control observed in wrist movements is also evident in the movement of hand-held objects and in the control of grip forces during movement execution (study 1) and planning (study 2). Furthermore, I investigated how task uncertainty interacts with hemispheric specialization in modes of grip forces control in both studies.</p><p dir="ltr">In study 1, I investigated whether grip force characteristics differ between hands during an ongoing bimanual manipulation. The right hand produced accurate object movement performance accompanied by stronger modulations in grip force in response to dynamics of loads associated with object movement compared to the left hand. In contrast, the left hand stabilized the object’s position better by exerting a higher grip force on the object. The main contribution of this study is that it suggests that the left hemisphere specializes in predicting dynamics of loads associated with object movements whereas the right hemisphere specializes in ensuring object’s stability by increasing its impedance.</p><p dir="ltr">In study 2, I investigated anticipatory modulations in grip force before an impending bimanual object manipulation task. I studied how each hand prepared grip force for the expected increase in load force, thereby uncovering differences in underlying motor planning processes of each hand. Grip force increased in both hands; however, this increase was greater in the left hand. This result indicates that the right hemisphere relies more on impedance control during planning. The main contribution of this study is that it suggests that even the motor planning processes that prepare each hand for an impending motor action are specialized in a way consistent with the predictions of dynamic dominance theory.</p><p dir="ltr">This dissertation adds to the existing knowledge about hemispheric specialization of arm movement control and extends it to grip force control. Future studies should focus on how the control of arm movements and grip force interact in each hemisphere. Furthermore, building on this dissertation, future work on pathology- and age-related dexterity loss could potentially lead to better interventions that improve the quality of life in these populations.</p>

No description available.

People use both their hands together cooperatively in many everyday activities. The modern computer interface fails to take advantage of this basic human ability, with the exception of the keyboard. However, the keyboard is limited in that it does not afford continuous spatial input. The computer mouse is perfectly suited for the point and click tasks that are the major method of manipulation within graphical user interfaces, but standard computers have a single mouse. A single mouse does not afford spatial coordination between the two hands within the graphical user interface. Although the advent of the Universal Serial Bus has made it possible to easily plug in many peripheral devices, including a second mouse, modern operating systems work on the assumption of a single spatial input stream. Thus, if a second mouse is plugged into a Macintosh computer, a Windows computer or a UNIX computer, the two mice control the same cursor. <br /><br /> Previous work in two-handed or bimanual interaction techniques has often followed the asymmetric interaction guidelines set out by Yves Guiard's Kinematic Chain Model. In asymmetric interaction, the hands are assigned different tasks, based on hand dominance. I show that there is an interesting class of desktop user interface tasks which can be classified as symmetric. A symmetric task is one in which the two hands contribute equally to the completion of a unified task. I show that dual-mouse symmetric interaction techniques outperform traditional single-mouse techniques as well as dual-mouse asymmetric techniques for these symmetric tasks. I also show that users prefer the symmetric interaction techniques for these naturally symmetric tasks.

People use both their hands together cooperatively in many everyday activities. The modern computer interface fails to take advantage of this basic human ability, with the exception of the keyboard. However, the keyboard is limited in that it does not afford continuous spatial input. The computer mouse is perfectly suited for the point and click tasks that are the major method of manipulation within graphical user interfaces, but standard computers have a single mouse. A single mouse does not afford spatial coordination between the two hands within the graphical user interface. Although the advent of the Universal Serial Bus has made it possible to easily plug in many peripheral devices, including a second mouse, modern operating systems work on the assumption of a single spatial input stream. Thus, if a second mouse is plugged into a Macintosh computer, a Windows computer or a UNIX computer, the two mice control the same cursor. <br /><br /> Previous work in two-handed or bimanual interaction techniques has often followed the asymmetric interaction guidelines set out by Yves Guiard's Kinematic Chain Model. In asymmetric interaction, the hands are assigned different tasks, based on hand dominance. I show that there is an interesting class of desktop user interface tasks which can be classified as symmetric. A symmetric task is one in which the two hands contribute equally to the completion of a unified task. I show that dual-mouse symmetric interaction techniques outperform traditional single-mouse techniques as well as dual-mouse asymmetric techniques for these symmetric tasks. I also show that users prefer the symmetric interaction techniques for these naturally symmetric tasks.

In dieser Arbeit wurde der Einsatz eines miniaturisierten Endoskop-Manipulator-Systems (EMS [TUM, MiMed, München]) in der endo- und transnasalen Chirurgie untersucht. In einem Modellversuch wurden an einem Nasennebenhöhlenmodell drei typische anatomische Landmarken je einmal manuell und zum Vergleich mit dem Endoskopmanipulator aufgesucht. Insgesamt wurden 240 Messwerte aufgenommen. Es wurden die benötigten Zeiten und die Genauigkeit der Endoskopposition gemessen. Grundlage des klinischen Versuchsteils war es, 31 funktionelle Nasennebenhöhleneingriffe durchzuführen. Dabei wurden die gewählten Endoskoppositionen, die Wechsel der Endoskoppositionen und die konzeptionsbedingten Unterbrechungen erfasst. Als Ausblick für eine Anwendung des EMS bei Operationen erhöhten Schwierigkeitsgrades wurde im Rahmen eines Kadaver-Versuches ein endoskopischer Zugang zur Hypophyse mit dem EMS erprobt. Es konnte weder im Laborversuch noch im klinischen Versuchsteil eine Unterlegenheit beim Einsatz des EMS bezüglich der Dauer und der Genauigkeit der assistierten Endoskopführung festgestellt werden. Die Anzahl der Positionswechsel lag durchschnittlich bei 6,4 pro Seite. Eine beidhändige Instrumentation war in allen untersuchten Fällen möglich, mit Ausnahme von Bereichen mit Hochrisikostruktu-ren (Lamina papyracea, Recessus frontalis), in welchen der Operateur aus Sicherheitsgründen auf eine manuelle Endoskopführung umstellte. Das untersuchte EMS wurde erfolgreich in den chirurgischen Workflow der endo- und transnasalen Chirurgie integriert, wobei die geringe Anzahl der Endoskoppositionswechsel eine beidhändige Instrumentation ermöglichte. Als Entwicklungspotenzial kann die Ergänzung der Joystickkonsole um eine Force-Feedback-Funktion bzw. die Möglichkeit einer rein navigiert-kontrollierten Steuerung hervorgehoben werden. Damit wird die Häufigkeit einer Unterbrechung des Workflows für die händische Steuerung über die Joystickkonsole minimiert.