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Charlottenlund, Denmark

Martiny K.M.,Copenhagen University | Martiny K.M.,Helene Elsass Center
Medicine, Health Care and Philosophy | Year: 2015

During recent decades various researchers from health and social sciences have been debating what it means for a person to be disabled. A rather overlooked approach has developed alongside this debate, primarily inspired by the philosophical tradition called phenomenology. This paper develops a phenomenological model of disability by arguing for a different methodological and conceptual framework from that used by the existing phenomenological approach. The existing approach is developed from the phenomenology of illness, but the paper illustrates how the case of congenital disabilities, looking at the congenital disorder called cerebral palsy (CP), presents a fundamental problem for the approach. In order to understand such congenital cases as CP, the experience of disability is described as being gradually different from, rather than a disruption of, the experience of being abled, and it is argued that the experience of disability is complex and dynamically influenced by both intrinsic and extrinsic factors. Different experiential aspects of disability— pre-reflective, attuned and reflective aspects—are described, demonstrating that the experience of disability comes in different degrees. Overall, this paper contributes to the debates about disability by further describing the personal aspects and experience of persons living with disabilities. © 2015, Springer Science+Business Media Dordrecht.

Petersen T.H.,Copenhagen University | Petersen T.H.,Helene Elsass Center | Farmer S.F.,University College London | Kliim-Due M.,Helene Elsass Center | And 2 more authors.
Journal of Neurophysiology | Year: 2013

Neurophysiological markers of the central control of gait in children with cerebral palsy (CP) are used to assess developmental response to therapy. We measured the central common drive to a leg muscle in children with CP. We recorded electromyograms (EMGs) from the tibialis anterior (TA) muscle of 40 children with hemiplegic CP and 42 typically developing age-matched controls during static dorsiflexion of the ankle and during the swing phase of treadmill walking. The common drive to TA motoneurons was identified through time- and frequency-domain cross-correlation methods. In control subjects, the common drive consists of frequencies between 1 and 60 Hz with peaks at beta (15-25 Hz) and gamma (30 - 45 Hz) frequencies known to be caused by activity within sensorimotor cortex networks: this drive to motoneurons strengthens during childhood. Similar to this drive in control subjects, this drive to the least affected TA in the CP children tended to strengthen with age, although compared with that in the control subjects, it was slightly weaker. For CP subjects of all ages, the most affected TA muscle common drive was markedly reduced compared with that of their least affected muscle as well as that of controls. These differences between the least and most affected TA muscles were unrelated to differences in the magnitude of EMG in the two muscles but positively correlated with ankle dorsiflexion velocity and joint angle during gait. Time- and frequency-domain analysis of ongoing EMG recruited during behaviorally relevant lower limb tasks provides a noninvasive and important measure of the central drive to motoneurons in subjects with CP. © 2013 the American Physiological Society.

Petersen T.H.,Norre Alle | Petersen T.H.,Helene Elsass Center | Kliim-Due M.,Helene Elsass Center | Farmer S.F.,University College London | And 2 more authors.
Journal of Physiology | Year: 2010

Corticospinal drive has been shown to contribute significantly to the control of walking in adult human subjects. It is unknown to what extent functional change in this drive is important for maturation of gait in children. In adults, populations of motor units within a muscle show synchronized discharges during walking with pronounced coherence in the 15-50 Hz frequency band. This coherence has been shown to depend on cortical drive. Here, we investigated how this coherence changes with development. Forty-four healthy children aged 4-15 years participated in the study. Electromyographic activity (EMG) was recorded from pairs of electrodes placed over the right tibialis anterior (TA) muscle during static dorsiflexion and during walking on a treadmill (speed from 1.8 to 4.8 km h-1). A significant increase of coherence with increasing age was found in the 30-45 Hz frequency band (gamma) during walking and during static ankle dorsiflexion. A significant correlation with age was also found in the 15-25 Hz frequency band (beta) during static foot dorsiflexion. χ2 analysis of differences of coherence between different age groups of children (4-6, 7-9, 10-12 and 13-15 years of age) revealed a significantly lower coherence in the gamma band for recordings during walking in children aged 4-6 years as compared to older children. Recordings during static dorsiflexion revealed significant differences in both the beta and gamma bands for children in the 4-6 and 7-9 years age groups as compared to the older age groups. A significant age-related decrease in step-to-step variability of toe position during the swing phase of walking was observed. This reduction in the step-to-step variability of gait was correlated with increased gamma band coherence during walking. We argue that this may reflect an increased ability to precisely control the ankle joint position with age, which may be contingent on maturation of corticospinal control of the foot dorsiflexor muscles. During childhood the human nervous system undergoes functional as well as structural changes. Such changes are responsible for the development of mature gait, which for the average child is seen around the age of 12 years. In this study we investigated healthy children aged 4-15 years during treadmill walking and found an increased synchronization of the input to spinal motoneurones that control the tibialis anterior muscle. We argue that this increased synchronization may be used as a marker of maturation of neural connections from the motor cortex to the spinal motoneurones. Precise control of the tibialis anterior muscle is necessary to safely lift the foot over the ground during the swing phase and to place it precisely on the ground in the early stance phase during walking. We observed a developmental decrease in the step-to-step variability in this control that could be related to the above described changes in synchronization. We therefore suggest that changes in the synchronous cortical drive to the spinal motoneurones may be responsible for the observed maturation of gait parameters. © 2010 The Authors. Journal compilation © 2010 The Physiological Society.

Willerslev-Olsen M.,Copenhagen University | Willerslev-Olsen M.,Helene Elsass Center | Lorentzen J.,Copenhagen University | Lorentzen J.,Helene Elsass Center | And 2 more authors.
Developmental Medicine and Child Neurology | Year: 2013

Aim: Clinical determination of spasticity is confounded by the difficulty in distinguishing reflex from passive contributions to muscle stiffness. There is, therefore, a risk that children with cerebral palsy (CP) receive antispasticity treatment unnecessarily. To investigate this, we aimed to determine the contribution of reflex mechanisms to changes in the passive elastic properties of muscles and tendons in children with CP. Method: Biomechanical and electrophysiological measures were used to determine the relative contribution of reflex and passive mechanisms to ankle muscle stiffness in 35 children with spastic CP (21 males, 14 females; mean age 9y, SD 3y 4mo; range 3-15y) and 28 control children without CP (19 males, nine females; mean age 8y 11mo, SD 2y 10mo; range 3-15y). Twenty-seven children were diagnosed as having spastic hemiplegia, six with spastic diplegia, and two with spastic tetraplegia. According to the Gross Motor Function Classification System, 31 children were classified in level I, two in level II, and two in level III. Results: Only seven children with spastic CP showed reflex stiffness outside the range of the control children. In contrast, 20 children with spastic CP showed abnormal passive muscle stiffness (p<0.001). No correlation between increased reflex or increased passive muscle stiffness and age was observed within the age range studied. Interpretation: These data suggest that increased reflex-mediated muscle stiffness is difficult to distinguish clinically from changes in passive muscle stiffness and that signs of changes in muscle properties are already present from the age of 3 years in children with CP. This emphasizes the importance of accurately distinguishing different contributions to muscle stiffness to avoid unnecessary antispasticity treatment. © The Authors. © 2013 Mac Keith Press.

Sgandurra G.,IRCCS Fondazione Stella Maris | Bartalena L.,University of Pisa | Cioni G.,University of Pisa | Greisen G.,Copenhagen University | And 7 more authors.
BMC Pediatrics | Year: 2015

Background: Preterm infants are at risk for neurodevelopmental disorders, including motor, cognitive or behavioural problems, which may potentially be modified by early intervention. The EU CareToy Project Consortium ( http://www.caretoy.eu ) has developed a new modular system for intensive, individualized, home-based and family-centred early intervention, managed remotely by rehabilitation staff. A randomised controlled trial (RCT) has been designed to evaluate the efficacy of CareToy training in a first sample of low-risk preterm infants. Methods/Design: The trial, randomised, multi-center, evaluator-blinded, parallel group controlled, is designed according to CONSORT Statement. Eligible subjects are infants born preterm without major complications, aged 3-9 months of corrected age with specific gross-motor abilities defined by Ages & Stages Questionnaire scores. Recruited infants, whose parents will sign a written informed consent for participation, will be randomized in CareToy training and control groups at baseline (T0). CareToy group will perform four weeks of personalized activities with the CareToy system, customized by the rehabilitation staff. The control group will continue standard care. Infant Motor Profile Scale is the primary outcome measure and a total sample size of 40 infants has been established. Bayley-Cognitive subscale, Alberta Infants Motor Scale and Teller Acuity Cards are secondary outcome measures. All measurements will be performed at T0 and at the end of training/control period (T1). For ethical reasons, after this first phase infants enrolled in the control group will perform the CareToy training, while the training group will continue standard care. At the end of open phase (T2) all infants will be assessed as at T1. Further assessment will be performed at 18 months corrected age (T3) to evaluate the long-term effects on neurodevelopmental outcome. Caregivers and rehabilitation staff will not be blinded whereas all the clinical assessments will be performed, videotaped and scored by blind assessors. The trial is ongoing and it is expected to be completed by April 2015. Discussion: This paper describes RCT methodology to evaluate CareToy as a new tool for early intervention in preterm infants, first contribution to test this new type of system. It presents background, hypotheses, outcome measures and trial methodology. Trial registration: ClinicalTrials.gov: NCT01990183 . EU grant ICT-2011.5.1-287932. © 2014 Sgandurra et al.; licensee BioMed Central Ltd.

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