Relative fascicle excursion effects on dynamic strength generation during gait in children with cerebral palsy

Evaluation of muscle structure gives us a better understanding of how muscles contribute to force generation which is significantly altered in children with cerebral palsy (CP). While most muscle structure parameters have shown to be significantly correlated to different expressions of strength development in children with CP and typically developing (TD) children, conflicting results are found for muscle fascicle length. Muscle fascicle length determines muscle excursion and velocity, and contrary to what might be expected, correlations of fascicle length to rate of force development have not been found for children with CP. The lack of correlation between muscle fascicle length and rate of force development in children with CP could be due, on the one hand, to the non-optimal joint position adopted for force generation on the isometric strength tests as compared to the position of TD children. On the other hand, the lack of correlation could be due to the erroneous assumption that muscle fascicle length is representative of sarcomere length. Thus, the relationship between muscle architecture parameters reflecting sarcomere length, such as relative fascicle excursions and dynamic power generation, should be assessed. Understanding of the underlying mechanisms of weakness in children with CP is key for individualized prescription and assessment of muscle-targeted interventions. Findings could imply the detection of children operating on the descending limb of the sarcomere length–tension curve, which in turn might be at greater risk of developing crouch gait. Furthermore, relative muscle fascicle excursions could be used as a predictive variable of outcomes related to crouch gait prevention treatments such as strength training

Actividad EEG durante dos tipos de estimulación sensitiva. A propósito de un caso.

[Objetivo] Entender mejor los fenómenos neurofisiológicos que acontecen a nivel cortical en el sujeto sano ante la exploración rutinaria de la sensibilidad.Peer reviewe

Effectiveness of Unihemispheric Concurrent Dual-Site Stimulation over M1 and Dorsolateral Prefrontal Cortex Stimulation on Pain Processing: A Triple Blind Cross-Over Control Trial.

Background: Transcranial direct current stimulation (tDCS) of the motor cortex (M1) produces short-term inhibition of pain. Unihemispheric concurrent dual-site tDCS (UHCDS-tDCS) over the M1 and dorsolateral prefrontal cortex (DLPFC) has greater effects on cortical excitability than when applied alone, although its effect on pain is unknown. The aim of this study was to test if anodal UHCDS-tDCS over the M1 and DLPFC in healthy participants could potentiate conditioned pain modulation (CPM) and diminish pain temporal summation (TS). Methods: Thirty participants were randomized to receive a sequence of UHCDS-tDCS, M1-tDCS and sham-tDCS. A 20 min 0.1 mA/cm2 anodal or sham-tDCS intervention was applied to each participant during three test sessions, according to a triple-blind cross-over trial design. For the assessment of pain processing before and after tDCS intervention, the following tests were performed: tourniquet conditioned pain modulation (CPM), pressure pain temporal summation (TS), pressure pain thresholds (PPTs), pressure pain tolerance, mechanosensitivity and cold hyperalgesia. Motor function before and after tDCS intervention was assessed with a dynamometer to measure maximal isometric grip strength. Results: No statistically significant differences were found between groups for CPM, pressure pain TS, PPT, pressure pain tolerance, neural mechanosensitivity, cold hyperalgesia or grip strength (p > 0.05). Conclusions: Neither UHCDS-tDCS nor M1-tDCS facilitated CPM or inhibited TS in healthy subjects following one intervention session.post-print3107 K

Locomotor training through a novel robotic platform for gait rehabilitation in pediatric population: short report

[Background] Cerebral Palsy (CP) is a disorder of posture and movement due to a defect in the immature brain. The use of robotic devices as alternative treatment to improve the gait function in patients with CP has increased. Nevertheless, current gait trainers are focused on controlling complete joint trajectories, avoiding postural control and the adaptation of the therapy to a specific patient. This paper presents the applicability of a new robotic platform called CPWalker in children with spastic diplegia.[Findings] CPWalker consists of a smart walker with body weight and autonomous locomotion support and an exoskeleton for joint motion support. Likewise, CPWalker enables strategies to improve postural control during walking. The integrated robotic platform provides means for testing novel gait rehabilitation therapies in subjects with CP and similar motor disorders. Patient-tailored therapies were programmed in the device for its evaluation in three children with spastic diplegia for 5 weeks. After ten sessions of personalized training with CPWalker, the children improved the mean velocity (51.94 ± 41.97 %), cadence (29.19 ± 33.36 %) and step length (26.49 ± 19.58 %) in each leg. Post-3D gait assessments provided kinematic outcomes closer to normal values than Pre-3D assessments.[Conclusions] The results show the potential of the novel robotic platform to serve as a rehabilitation tool. The autonomous locomotion and impedance control enhanced the children’s participation during therapies. Moreover, participants’ postural control was substantially improved, which indicates the usefulness of the approach based on promoting the patient’s trunk control while the locomotion therapy is executed. Although results are promising, further studies with bigger sample size are required.The work presented in this paper has been carried out with the financial support from the Ministerio de Economía y Competitividad of Spain, under Contract DPI2012-39133-C03-01.Peer reviewe

Entrenamiento robótico de la marcha en pacientes con Parálisis Cerebral: definición de objetivos, propuesta de tratamiento e implementación clínica preliminar

[Resumen] El uso de dispositivos robóticos para rehabilitación de la marcha se ha incrementado en los últimos años de manera notable. Sin embargo, hay una falta de estudios que proporcionen pautas detalladas sobre cómo usar la robótica de rehabilitación para obtener los máximos beneficios del tratamiento. Esta contribución presenta un programa de entrenamiento detallado para rehabilitación robótica de la marcha de niños con Parálisis Cerebral (PC). Éste está centrado en la consecución de diferentes especificaciones de la International Classification of Functioning, Disability and Health framework, Children and Youth version (ICF-CY). El programa de entrenamiento se divide en 16 sesiones, en las que los pacientes trabajan control motor, fuerza y potencia en sus extremidades inferiores. Resultados de una validación clínica con 4 pacientes pediátricos muestran mejoras en diferentes aspectos de la marcha, tales como velocidad, fuerza, longitud de paso o desempeño según la Gross Motor Function Measure-88. Este estudio fue registrado públicamente con el número ISRCTN18254257 el 23 de Marzo de 2017

Entrenamiento y rehabilitación de la marcha en pacientes pediátricos a través de la plataforma robótica CPWalker

[Resumen] La Parálisis Cerebral (PC) está relacionada con un trastorno de la postura y el movimiento debido a una lesión ocasionada en el cerebro cuando éste no se ha desarrollado completamente. Al ser una de las discapacidades más prevalentes a edades tempranas, la investigación y el desarrollo de dispositivos robóticos para la rehabilitación de la marcha en estos pacientes ha incrementado en los últimos tiempos. Sin embargo, los dispositivos actuales están enfocados sólo en controlar trayectorias de movimiento, olvidando el control postural del usuario y la adaptación de la terapia a las necesidades específicas de cada paciente. Este documento presenta los resultados preliminares de la aplicación de una nueva plataforma robótica (CPWalker) en la rehabilitación de la marcha de niños con diplejía espástica, durante una validación de cinco semanas. CPWalker está formado por un andador inteligente con sistema de control de peso y locomoción autónoma y un exoesqueleto robótico que realiza el movimiento guiado de las articulaciones. Además, el dispositivo incluye la posibilidad de mejorar el control postural del paciente durante la marcha, adaptando la terapia a las necesidades demandadas por el usuario.El trabajo presentado en este documento ha sido financiado por el Ministerio de Economía y Competitividad español, a través del contrato DPI2012-39133-C03-01https://doi.org/10.17979/spudc.978849749808

Azimuthal anisotropy of charged jet production in root s(NN)=2.76 TeV Pb-Pb collisions

We present measurements of the azimuthal dependence of charged jet production in central and semi-central root s(NN) = 2.76 TeV Pb-Pb collisions with respect to the second harmonic event plane, quantified as nu(ch)(2) (jet). Jet finding is performed employing the anti-k(T) algorithm with a resolution parameter R = 0.2 using charged tracks from the ALICE tracking system. The contribution of the azimuthal anisotropy of the underlying event is taken into account event-by-event. The remaining (statistical) region-to-region fluctuations are removed on an ensemble basis by unfolding the jet spectra for different event plane orientations independently. Significant non-zero nu(ch)(2) (jet) is observed in semi-central collisions (30-50% centrality) for 20 <p(T)(ch) (jet) <90 GeV/c. The azimuthal dependence of the charged jet production is similar to the dependence observed for jets comprising both charged and neutral fragments, and compatible with measurements of the nu(2) of single charged particles at high p(T). Good agreement between the data and predictions from JEWEL, an event generator simulating parton shower evolution in the presence of a dense QCD medium, is found in semi-central collisions. (C) 2015 CERN for the benefit of the ALICE Collaboration. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).Peer reviewe

Production of He-4 and (4) in Pb-Pb collisions at root(NN)-N-S=2.76 TeV at the LHC

Results on the production of He-4 and (4) nuclei in Pb-Pb collisions at root(NN)-N-S = 2.76 TeV in the rapidity range vertical bar y vertical bar <1, using the ALICE detector, are presented in this paper. The rapidity densities corresponding to 0-10% central events are found to be dN/dy4(He) = (0.8 +/- 0.4 (stat) +/- 0.3 (syst)) x 10(-6) and dN/dy4 = (1.1 +/- 0.4 (stat) +/- 0.2 (syst)) x 10(-6), respectively. This is in agreement with the statistical thermal model expectation assuming the same chemical freeze-out temperature (T-chem = 156 MeV) as for light hadrons. The measured ratio of (4)/He-4 is 1.4 +/- 0.8 (stat) +/- 0.5 (syst). (C) 2018 Published by Elsevier B.V.Peer reviewe