Birth prevalence of isolated congenital limb reduction defects in Texas 1999--2001

Objective. Congenital limb defects are common birth defects occurring in approximately 2-7/10,000 live births. Because congenital limb defects are pervasive throughout all populations, and the conditions profoundly affect quality of life, they represent a significant public health concern. Currently there is a paucity of etiologic information in the literature regarding congenital limb reduction defects which represents a major limitation in developing treatment strategies as well as identifying high risk pregnancies. ^ Additionally, despite the fact that the majority of congenital limb reduction defects are isolated, most previous studies have not separated them from those occurring as part of a known syndrome or with multiple additional congenital anomalies of unknown etiology. It stands to reason that factors responsible for multiple congenital anomalies that happen to include congenital limb reduction defects may be quite different from those factors leading to an isolated congenital limb reduction defect. ^ As a first step toward gaining etiologic understanding, this cross-sectional study was undertaken to determine the birth prevalence and obtain demographic information about non-syndromic (isolated) congenital limb reduction defects that occurred in Texas from 1999-2001. ^ Methods. The study population included all infants/fetuses with isolated congenital limb reduction defects born in Texas during 1999-2001; the comparison population was all infants who were born to mothers who were residents of Texas during the same period of time. The overall birth prevalence of limb reduction defects was determined and adjusted for ethnicity, gender, site of defect (upper limb versus lower limb), county of residence, maternal age and maternal education. ^ Results. In Texas, the overall birth prevalence of isolated CLRDs was 2.1/10,000 live births (1.5 and 0.6/10,000 live births for upper limb and lower limb, respectively). ^ The risk of isolated lower limb CLRDs in Texas was significantly lower in females when gender was examined individually (crude prevalence odds ratio of 0.57, 95% CI of 0.36-0.91) as well as in relation to all other variables used in the analysis (adjusted prevalence odds ratio of 0.58, 95% CI of 0.36-0.93). ^ Harris County (which includes the Houston metropolitan area) had significantly lower risks of all (upper limb and lower limb combined) isolated CLRDs when examined in relation to other counties in Texas, with a crude prevalence odds ratio of 0.4 (95% CI: 0.29-0.72) and an adjusted prevalence odds ratio of 0.50 (95% CI: 0.31-0.80). The risk of isolated upper limb CLRDs was significantly lower in Harris County (crude prevalence odds ratio of 0.45, CI of 0.26-0.76 and adjusted prevalence odds ratio of 0.49, CI of 0.28-0.84). This trend toward decreased risk in Harris County was not observed for isolated lower limb reduction defects (adjusted prevalence odds ratio of 0.50, 95% confidence interval: 0.22-1.12). ^ Conclusions. The birth prevalence of isolated congenital limb reduction defects in Texas is in the lower limits of the range of rates that have been reported by other authors for other states (Alabama, Arkansas, California, Georgia, Hawaii, Iowa, Maryland, Massachusetts, North Carolina, Oklahoma, Utah, Washington) and other countries (Argentina, Australia, Austria, Bolivia, Brazil, Canada, Chile, China, Colombia, Costa Rica, Croatia, Denmark, Ecuador, England, Finland, France, Germany, Hungary, Ireland, Israel, Italy, Lithuania, Mexico, Norway, Paraguay, Peru, Spain, Scotland, Sweden, Switzerland, Uruguay, and Venezuela). In Texas, the birth prevalence of isolated congenital lower limb reduction defects was greater for males than females, while the birth prevalence of isolated congenital upper limb reduction defects was not significantly different between males and females. The reduced rates of limb reduction defects in Harris County warrant further investigation. This study has provided an important first step toward gaining etiologic understanding in the study of isolated congenital limb reduction defects. ^

Metodologías de modelado, monitorización y asistencia robótica en neurorrehabilitación funcional de extremidad superior

La Organización Mundial de la Salud (OMS) prevé que para el año 2020, el Daño Cerebral Adquirido (DCA) estará entre las 10 causas más comunes de discapacidad. Estas lesiones, dadas sus consecuencias físicas, sensoriales, cognitivas, emocionales y socioeconómicas, cambian dramáticamente la vida de los pacientes y sus familias. Las nuevas técnicas de intervención precoz y el desarrollo de la medicina intensiva en la atención al DCA han mejorado notablemente la probabilidad de supervivencia. Sin embargo, hoy por hoy, las lesiones cerebrales no tienen ningún tratamiento quirúrgico que tenga por objetivo restablecer la funcionalidad perdida, sino que las terapias rehabilitadoras se dirigen hacia la compensación de los déficits producidos. Uno de los objetivos principales de la neurorrehabilitación es, por tanto, dotar al paciente de la capacidad necesaria para ejecutar las Actividades de Vida Diaria (AVDs) necesarias para desarrollar una vida independiente, siendo fundamentales aquellas en las que la Extremidad Superior (ES) está directamente implicada, dada su gran importancia a la hora de la manipulación de objetos. Con la incorporación de nuevas soluciones tecnológicas al proceso de neurorrehabilitación se pretende alcanzar un nuevo paradigma centrado en ofrecer una práctica personalizada, monitorizada y ubicua con una valoración continua de la eficacia y de la eficiencia de los procedimientos y con capacidad de generar conocimientos que impulsen la ruptura del paradigma de actual. Los nuevos objetivos consistirán en minimizar el impacto de las enfermedades que afectan a la capacidad funcional de las personas, disminuir el tiempo de incapacidad y permitir una gestión más eficiente de los recursos. Estos objetivos clínicos, de gran impacto socio-económico, sólo pueden alcanzarse desde una apuesta decidida en nuevas tecnologías, metodologías y algoritmos capaces de ocasionar la ruptura tecnológica necesaria que permita superar las barreras que hasta el momento han impedido la penetración tecnológica en el campo de la rehabilitación de manera universal. De esta forma, los trabajos y resultados alcanzados en la Tesis son los siguientes: 1. Modelado de AVDs: como paso previo a la incorporación de ayudas tecnológicas al proceso rehabilitador, se hace necesaria una primera fase de modelado y formalización del conocimiento asociado a la ejecución de las actividades que se realizan como parte de la terapia. En particular, las tareas más complejas y a su vez con mayor repercusión terapéutica son las AVDs, cuya formalización permitirá disponer de modelos de movimiento sanos que actuarán de referencia para futuros desarrollos tecnológicos dirigidos a personas con DCA. Siguiendo una metodología basada en diagramas de estados UML se han modelado las AVDs 'servir agua de una jarra' y 'coger un botella' 2. Monitorización ubícua del movimiento de la ES: se ha diseñado, desarrollado y validado un sistema de adquisición de movimiento basado en tecnología inercial que mejora las limitaciones de los dispositivos comerciales actuales (coste muy elevado e incapacidad para trabajar en entornos no controlados); los altos coeficientes de correlación y los bajos niveles de error obtenidos en los corregistros llevados a cabo con el sistema comercial BTS SMART-D demuestran la alta precisión del sistema. También se ha realizado un trabajo de investigación exploratorio de un sistema de captura de movimiento de coste muy reducido basado en visión estereoscópica, habiéndose detectado los puntos clave donde se hace necesario incidir desde un punto de vista tecnológico para su incorporación en un entorno real 3. Resolución del Problema Cinemático Inverso (PCI): se ha diseñado, desarrollado y validado una solución al PCI cuando el manipulador se corresponde con una ES humana estudiándose 2 posibles alternativas, una basada en la utilización de un Perceptrón Multicapa (PMC) y otra basada en sistemas Artificial Neuro-Fuzzy Inference Systems (ANFIS). La validación, llevada a cabo utilizando información relativa a los modelos disponibles de AVDs, indica que una solución basada en un PMC con 3 neuronas en la capa de entrada, una capa oculta también de 3 neuronas y una capa de salida con tantas neuronas como Grados de Libertad (GdLs) tenga el modelo de la ES, proporciona resultados, tanto de precisión como de tiempo de cálculo, que la hacen idónea para trabajar en sistemas con requisitos de tiempo real 4. Control inteligente assisted-as-needed: se ha diseñado, desarrollado y validado un algoritmo de control assisted-as-needed para una ortesis robótica con capacidades de actuación anticipatoria de la que existe un prototipo implementado en la actualidad. Los resultados obtenidos demuestran cómo el sistema es capaz de adaptarse al perfil disfuncional del paciente activando la ayuda en instantes anteriores a la ocurrencia de movimientos incorrectos. Esta estrategia implica un aumento en la participación del paciente y, por tanto, en su actividad muscular, fomentándose los procesos la plasticidad cerebral responsables del reaprendizaje o readaptación motora 5. Simuladores robóticos para planificación: se propone la utilización de un simulador robótico assisted-as-needed como herramienta de planificación de sesiones de rehabilitación personalizadas y con un objetivo clínico marcado en las que interviene una ortesis robotizada. Los resultados obtenidos evidencian como, tras la ejecución de ciertos algoritmos sencillos, es posible seleccionar automáticamente una configuración para el algoritmo de control assisted-as-needed que consigue que la ortesis se adapte a los criterios establecidos desde un punto de vista clínico en función del paciente estudiado. Estos resultados invitan a profundizar en el desarrollo de algoritmos más avanzados de selección de parámetros a partir de baterías de simulaciones Estos trabajos han servido para corroborar las hipótesis de investigación planteadas al inicio de la misma, permitiendo, asimismo, la apertura de nuevas líneas de investigación. Summary The World Health Organization (WHO) predicts that by the year 2020, Acquired Brain Injury (ABI) will be among the ten most common ailments. These injuries dramatically change the life of the patients and their families due to their physical, sensory, cognitive, emotional and socio-economic consequences. New techniques of early intervention and the development of intensive ABI care have noticeably improved the survival rate. However, in spite of these advances, brain injuries still have no surgical or pharmacological treatment to re-establish the lost functions. Neurorehabilitation therapies address this problem by restoring, minimizing or compensating the functional alterations in a person disabled because of a nervous system injury. One of the main objectives of Neurorehabilitation is to provide patients with the capacity to perform specific Activities of the Daily Life (ADL) required for an independent life, especially those in which the Upper Limb (UL) is directly involved due to its great importance in manipulating objects within the patients' environment. The incorporation of new technological aids to the neurorehabilitation process tries to reach a new paradigm focused on offering a personalized, monitored and ubiquitous practise with continuous assessment of both the efficacy and the efficiency of the procedures and with the capacity of generating new knowledge. New targets will be to minimize the impact of the sicknesses affecting the functional capabilitiies of the subjects, to decrease the time of the physical handicap and to allow a more efficient resources handling. These targets, of a great socio-economic impact, can only be achieved by means of new technologies and algorithms able to provoke the technological break needed to beat the barriers that are stopping the universal penetration of the technology in the field of rehabilitation. In this way, this PhD Thesis has achieved the following results: 1. ADL Modeling: as a previous step to the incorporation of technological aids to the neurorehabilitation process, it is necessary a first modelling and formalization phase of the knowledge associated to the execution of the activities that are performed as a part of the therapy. In particular, the most complex and therapeutically relevant tasks are the ADLs, whose formalization will produce healthy motion models to be used as a reference for future technological developments. Following a methodology based on UML state-chart diagrams, the ADLs 'serving water from a jar' and 'picking up a bottle' have been modelled 2. Ubiquitous monitoring of the UL movement: it has been designed, developed and validated a motion acquisition system based on inertial technology that improves the limitations of the current devices (high monetary cost and inability of working within uncontrolled environments); the high correlation coefficients and the low error levels obtained throughout several co-registration sessions with the commercial sys- tem BTS SMART-D show the high precision of the system. Besides an exploration of a very low cost stereoscopic vision-based motion capture system has been carried out and the key points where it is necessary to insist from a technological point of view have been detected 3. Inverse Kinematics (IK) problem solving: a solution to the IK problem has been proposed for a manipulator that corresponds to a human UL. This solution has been faced by means of two different alternatives, one based on a Mulilayer Perceptron (MLP) and another based on Artificial Neuro-Fuzzy Inference Systems (ANFIS). The validation of these solutions, carried out using the information regarding the previously generated motion models, indicate that a MLP-based solution, with an architecture consisting in 3 neurons in the input layer, one hidden layer of 3 neurons and an output layer with as many neurons as the number of Degrees of Freedom (DoFs) that the UL model has, is the one that provides the best results both in terms of precission and in terms of processing time, making in idoneous to be integrated within a system with real time restrictions 4. Assisted-as-needed intelligent control: an assisted-as-needed control algorithm with anticipatory actuation capabilities has been designed, developed and validated for a robotic orthosis of which there is an already implemented prototype. Obtained results demonstrate that the control system is able to adapt to the dysfunctional profile of the patient by triggering the assistance right before an incorrect movement is going to take place. This strategy implies an increase in the participation of the patients and in his or her muscle activity, encouraging the neural plasticity processes in charge of the motor learning 5. Planification with a robotic simulator: in this work a robotic simulator is proposed as a planification tool for personalized rehabilitation sessions under a certain clinical criterium. Obtained results indicate that, after the execution of simple parameter selection algorithms, it is possible to automatically choose a specific configuration that makes the assisted-as-needed control algorithm to adapt both to the clinical criteria and to the patient. These results invite researchers to work in the development of more complex parameter selection algorithms departing from simulation batteries Obtained results have been useful to corroborate the hypotheses set out at the beginning of this PhD Thesis. Besides, they have allowed the creation of new research lines in all the studied application fields.

A novel motion tracking system for evaluation of functional rehabilitation of the upper limbs

Upper limb function impairment is one of the most common sequelae of central nervous system injury, especially in stroke patients and when spinal cord injury produces tetraplegia. Conventional assessment methods cannot provide objective evaluation of patient performance and the tiveness of therapies. The most common assessment tools are based on rating scales, which are inefficient when measuring small changes and can yield subjective bias. In this study, we designed an inertial sensor-based monitoring system composed of five sensors to measure and analyze the complex movements of the upper limbs, which are common in activities of daily living. We developed a kinematic model with nine degrees of freedom to analyze upper limb and head movements in three dimensions. This system was then validated using a commercial optoelectronic system. These findings suggest that an inertial sensor-based motion tracking system can be used in patients who have upper limb impairment through data integration with a virtual reality-based neuroretation system.

Definición e implementación de métricas objetivas para la evaluación funcional del miembro superior: aplicación a población con lesión medular cervical

En personas que padecen una Lesión Medular cervical, la función de los miembros superiores se ve afectada en mayor o menor medida, dependiendo fundamentalmente del nivel de la lesión y de la severidad de la misma. El déficit en la función del miembro superior hace que la autonomía e independencia de las personas se vea reducida en la ejecución de Actividades de la Vida Diaria. En el entorno clínico, la valoración de la función del miembro superior se realiza principalmente con escalas clínicas. Algunas de ellas valoran el nivel de dependencia o independencia en la ejecución de Actividades de la Vida Diaria, como, por ejemplo, el índice de Barthel y la escala FIM (Medida de la Independencia Funcional). Otras escalas, como Jebsen-Taylor Hand Function, miden la función del miembro superior valorando la destreza y la habilidad en la ejecución de determinadas tareas funcionales. Estas escalas son generales, es decir, se pueden aplicar a distintas poblaciones de sujetos y a la presencia de distintas patologías. Sin embargo, existen otras escalas desarrolladas específicamente para valorar una patología concreta, con el objetivo de hacer las evaluaciones funcionales más sensibles a cambios. Un ejemplo es la escala Spinal Cord Independence Measure (SCIM), desarrollada para valorar Lesión Medular. Las escalas clínicas son instrumentos de medida estandarizados, válidos para su uso en el entorno clínico porque se han validado en muestras grandes de pacientes. No obstante, suelen poseer una elevada componente de subjetividad que depende principalmente de la persona que puntúa el test. Otro aspecto a tener en cuenta, es que la sensibilidad de las escalas es alta, fundamentalmente, a cambios groseros en el estado de salud o en la función del miembro superior, de forma que cambios sutiles en el sujeto pueden no ser detectados. Además, en ocasiones, poseen saturaciones en el sistema de puntuación, de forma que mejorías que se puedan producir por encima de un determinado umbral no son detectadas. En definitiva, estas limitaciones hacen que las escalas clínicas no sean suficientes, por sí mismas, para evaluar estrategias motoras del miembro superior durante la ejecución de movimientos funcionales, siendo necesaria la búsqueda de instrumentos de medida que aporten objetividad, complementen las valoraciones y, al mismo tiempo, intenten solventar las limitaciones que poseen las escalas. Los estudios biomecánicos son ejemplos de métodos objetivos, en los que diversas tecnologías se pueden utilizar para recoger información de los sujetos. Una concreción de estos estudios son los estudios cinemáticos. Mediante tecnología optoelectrónica, inercial o electromagnética, estos estudios proporcionan información objetiva acerca del movimiento realizado por los sujetos, durante la ejecución de tareas concretas. Estos sistemas de medida proporcionan grandes cantidades de datos que carecen de una interpretación inmediata. Estos datos necesariamente deben ser tratados y reducidos a un conjunto de variables que, a priori, posean una interpretación más sencilla para ser utilizados en la práctica clínica. Estas han sido las principales motivaciones de esta investigación. El objetivo principal fue proponer un conjunto de índices cinemáticos que, de forma objetiva, valoren la función del miembro superior; y validar los índices propuestos en poblaciones con Lesión Medular, para su uso como instrumentos de valoración en el entorno clínico. Esta tesis se enmarca dentro de un proyecto de investigación: HYPER (Hybrid Neuroprosthetic and Neurorobotic Devices for Functional Compensation and Rehabilitation of Motor Disorders, referencia CSD2009-00067 CONSOLIDER INGENIO 2010). Dentro de este proyecto se lleva a cabo investigación en el desarrollo de modelos, para determinar los requisitos biomecánicos y los patrones de movimiento de los miembros superiores en sujetos sanos y personas con lesión medular. Además, se realiza investigación en la propuesta de nuevos instrumentos de evaluación funcional en el campo de la rehabilitación de los miembros superiores. ABSTRACT In people who have suffered a cervical Spinal Cord Injury, upper limbs function is affected to a greater or lesser extent, depending primarily on the level of the injury and the severity of it. The deficit in the upper limb function reduces the autonomy and independence of persons in the execution of Activities of Daily Living. In the clinical setting, assessment of upper limb function is mainly performed based on clinical scales. Some value the level of dependence or independence in performing activities of daily living, such as the Barthel Index and the FIM scale (Functional Independence Measure). Other scales, such as the Jebsen-Taylor Hand Function, measure upper limb function in terms of the skill and ability to perform specific functional tasks. These scales are general, so can be applied to different populations of subjects and the presence of different pathologies. However, there are other scales developed for a specific injury, in order to make the functional assessments more sensitive to changes. An example is the Spinal Cord Independence Measure (SCIM), developed for people with Spinal Cord Injury. The clinical scales are standardized instruments measure, valid for use in the clinical setting because they have been validated in large patient samples. However, they usually have a high level of subjectivity which mainly depends on the person who scores the test. Another aspect to take into account is the high sensitivity of the scales mainly to gross changes in the health status or upper limb function, so that subtle changes in the subject may not be detected. Moreover, sometimes, have saturations in the scoring system, so that improvements which may occur above a certain threshold are not detected. For these reasons, clinical scales are not enough, by themselves, to assess motor strategies used during movements. So, it’s necessary to find measure instruments that provide objectivity, supplement the assessments and, at the same time, solving the limitations that scales have. Biomechanical studies are examples of objective methods, in which several technologies can be used to collect information from the subjects. One kind of these studies is the kinematic movement analysis. By means of optoelectronics, inertial and electromagnetic technology, these studies provide objective information about the movement performed by the subjects during the execution of specific tasks. These systems provide large quantities of data without easy and intuitive interpretation. These data must necessarily be treated and reduced to a set of variables that, a priori, having a simpler interpretation for their use in the clinical practice. These were the main motivations of this research. The main objective was to propose a set of kinematic indices, or metrics that, objectively, assess the upper limb function and validate the proposed rates in populations with Spinal Cord Injury, for use as assessment tools in the clinical setting. This dissertation is framed within a research project: HYPER (Neurorobotic Devices for Functional Compensation and Rehabilitation of Motor Disorders, grant CSD2009- 00067 CONSOLIDER INGENIO 2010). Within this research project, research is conducted in relation to the biomechanical models development for determining the biomechanical requirements and movement patterns of the upper limb in healthy and people with Spinal Cord Injury. Moreover, research is conducted with respect to the proposed of new functional assessment instruments in the field of upper limb rehabilitation.

Isometric strength of the upper extremities in Czech men older than 18 years

The aim of this study was to compare isometric strength of the upper extremities in a sample of men from the Czech republic (n=638). Only the dominant upper limb was tested. The examined subjects were 18 years old or older. The measured values (in kilograms) were obtained via hand-held dynamometry testing (a digital hand-held dynamometer). The results of the hand-held dynamometry testing were compared across six age categories (18-29, 30-39, 40-49.... 70+ years). It was found that isometric strength of the dominant upper limb in men increases up to the age group 30-39 years and then declines. The highest average value (55.6 kg) was found in the age group 30-39 years, and expectably, the lowest values (34.4 kg) were documented in the age category 70+ years. The largest decline in isometric strength (-8.8 kg) was found between the age groups 60-69 years and 70+ years.

Caractérisation tridimensionnelle de l’amplitude articulaire de l’épaule

L’épaule est l’articulation la plus mobile et la plus instable du corps humain dû à la faible quantité de contraintes osseuses et au rôle des tissus mous qui lui confèrent au moins une dizaine de degrés de liberté. La mobilité de l’épaule est un facteur de performance dans plusieurs sports. Mais son instabilité engendre des troubles musculo-squelettiques, dont les déchirures de la coiffe des rotateurs sont fréquentes et les plus handicapantes. L’évaluation de l’amplitude articulaire est un indice commun de la fonction de l’épaule, toutefois elle est souvent limitée à quelques mesures planaires pour lesquelles les degrés de liberté varient indépendamment les uns des autres. Ces valeurs utilisées dans les modèles de simulation musculo-squelettiques peuvent amener à des solutions non physiologiques. L’objectif de cette thèse était de développer des outils pour la caractérisation de la mobilité articulaire tri-dimensionnelle de l’épaule, en passant par i) fournir une méthode et son approche expérimentale pour évaluer l’amplitude articulaire tridimensionnelle de l’épaule incluant des interactions entre les degrés de liberté ; ii) proposer une représentation permettant d’interpréter les données tri-dimensionnelles obtenues; iii) présenter des amplitudes articulaires normalisées, iv) implémenter une amplitude articulaire tridimensionnelle au sein d’un modèle de simulation numérique afin de générer des mouvements sportifs optimaux plus réalistes; v) prédire des amplitudes articulaires sécuritaires et vi) des exercices de rééducation sécuritaires pour des patients ayant subi une réparation de la coiffe des rotateurs. i) Seize sujets ont été réalisé séries de mouvements d’amplitudes maximales actifs avec des combinaisons entre les différents degrés de liberté de l’épaule. Un système d’analyse du mouvement couplé à un modèle cinématique du membre supérieur a été utilisé pour estimer les cinématiques articulaires tridimensionnelles. ii) L’ensemble des orientations définies par une séquence de trois angles a été inclus dans un polyèdre non convexe représentant l’espace de mobilité articulaire prenant en compte les interactions entre les degrés de liberté. La combinaison des séries d’élévation et de rotation est recommandée pour évaluer l’amplitude articulaire complète de l’épaule. iii) Un espace de mobilité normalisé a également été défini en englobant les positions atteintes par au moins 50% des sujets et de volume moyen. iv) Cet espace moyen, définissant la mobilité physiologiques, a été utilisé au sein d’un modèle de simulation cinématique utilisé pour optimiser la technique d’un élément acrobatique de lâcher de barres réalisée par des gymnastes. Avec l’utilisation régulière de limites articulaires planaires pour contraindre la mobilité de l’épaule, seulement 17% des solutions optimales sont physiologiques. En plus, d’assurer le réalisme des solutions, notre contrainte articulaire tridimensionnelle n’a pas affecté le coût de calculs de l’optimisation. v) et vi) Les seize participants ont également réalisé des séries d’amplitudes articulaires passives et des exercices de rééducation passifs. La contrainte dans l’ensemble des muscles de la coiffe des rotateurs au cours de ces mouvements a été estimée à l’aide d’un modèle musculo-squelettique reproduisant différents types et tailles de déchirures. Des seuils de contrainte sécuritaires ont été utilisés pour distinguer les amplitudes de mouvements risquées ou non pour l’intégrité de la réparation chirurgicale. Une taille de déchirure plus grande ainsi que les déchirures affectant plusieurs muscles ont contribué à réduire l’espace de mobilité articulaire sécuritaire. Principalement les élévations gléno-humérales inférieures à 38° et supérieures à 65°, ou réalisées avec le bras maintenu en rotation interne engendrent des contraintes excessives pour la plupart des types et des tailles de blessure lors de mouvements d’abduction, de scaption ou de flexion. Cette thèse a développé une représentation innovante de la mobilité de l’épaule, qui tient compte des interactions entre les degrés de liberté. Grâce à cette représentation, l’évaluation clinique pourra être plus exhaustive et donc élargir les possibilités de diagnostiquer les troubles de l’épaule. La simulation de mouvement peut maintenant être plus réaliste. Finalement, nous avons montré l’importance de personnaliser la rééducation des patients en termes d’amplitude articulaire, puisque des exercices passifs de rééducation précoces peuvent contribuer à une re-déchirure à cause d’une contrainte trop importante qu’ils imposent aux tendons.

Unravelling the complexity of muscle impairment in chronic neck pain

Exercise interventions are deemed essential for the effective management of patients with neck pain. However, there has been a lack of consensus on optimal exercise prescription, which has resulted from a paucity of studies to quantify the precise nature of muscle impairment, in people with neck pain. This masterclass will present recent research from our laboratory, which has utilized surface electromyography to investigate cervical flexor muscle impairment in patients with chronic neck pain. This research has identified deficits in the motor control of the deep and superficial cervical flexor muscles in people with chronic neck pain, characterized by a delay in onset of neck muscle contraction associated with movement of the upper limb. In addition, people with neck pain demonstrate an altered pattern of muscle activation, which is characterized by reduced deep cervical flexor muscle activity during a low load cognitive task and increased activity of the superficial cervical flexor muscles during both cognitive tasks and functional activities. The results have demonstrated the complex, multifaceted nature of cervical muscle impairment, which exists in people with a history of neck pain. In turn, this has considerable implications for the rehabilitation of muscle function in people with neck pain disorders. (C) 2004 Elsevier Ltd. All rights reserved.

Standing with assistance of a tilt table in intensive care: A survey of Australian physiotherapy practice

Although tilt tables are used by physiotherapists to reintroduce patients to the vertical position, no quantitative evidence is available regarding their use within intensive care units (ICUs) of Australian hospitals. The purpose of this study was to evaluate the use of tilt tables in physiotherapy management of patients in ICUs across Australia. Ninety-nine physiotherapists working in Australian public ICUs were contacted via mail and asked to complete a questionnaire regarding their use of tilt tables in practice. Reasons for the use of the tilt table, contraindications, commonly used adjuncts, monitoring, and outcome measures were also investigated. Eighty-six questionnaires were returned (87% response). The tilt table was used by 58 physiotherapists (67.4%). The most common reasons for inclusion of tilt table treatment were to: facilitate weight bearing (94.8% of those who tilt); prevent muscle contractures (86%); improve lower limb strength (81%); and increase arousal (70%). The tilt table was most frequently applied to patients with neurological conditions (63.8%) and during long-term ICU stay (43.1%). Techniques often combined with tilt table treatment included upper limb exercises (93.1%) and breathing exercises (86.2%). Standing with assistance of the tilt table is used by the majority of physiotherapists working in Australian ICUs. A moderate level of agreement is demonstrated by physiotherapists regarding indications to commence tilt table treatment and adjunct modalities combined with standing with assistance of the tilt table.

Changes in head and neck position affect elbow joint position sense

Changes in the position of the head and neck have been shown to introduce a systematic deviation in the end-point error of an upper limb pointing task. Although previous authors have attributed this to alteration of perceived target location, no studies have explored the effect of changes in head and neck position on the perception of limb position. This study investigated whether changes in head and neck position affect a specific component of movement performance, that is, the accuracy of joint position sense (JPS) at the elbow. Elbow JPS was tested with the neck in four positions: neutral, flexion, rotation and combined flexion/rotation. A target angle was presented passively with the neck in neutral, after a rest period; this angle was reproduced actively with the head and neck in one of the test positions. The potential effects of distraction from head movement were controlled for by performing a movement control in which the head and neck were in neutral for the presentation and reproduction of the target angle, but moved into flexion during the rest period. The absolute and variable joint position errors (JPE) were greater when the target angle was reproduced with the neck in the flexion, rotation, and combined flexion/rotation than when the head and neck were in neutral. This study suggests that the reduced accuracy previously seen in pointing tasks with changes in head position may be partly because of errors in the interpretation of arm position.

Do you know where your arm is if you think your head has moved?

Reproduction of a previously presented elbow position is affected by changes in head position. As movement of the head is associated with local biomechanical changes, the aim of the present study was to determine if illusory changes in head position could induce similar effects on the reproduction of elbow position. Galvanic vestibular stimulation (GVS) was applied to healthy subjects in supine lying. The stimulus was applied during the presentation of an elbow position, which the subject then reproduced without stimulation. In the first study, 13 subjects received 1.5 mA stimuli, which caused postural sway in standing, confirming that the firing of vestibular afferents was affected, but no illusory changes in head position were reported. In the second study, 13 subjects received 2.0-3.0 mA GVS. Six out of 13 subjects reported consistent illusory changes in head position, away from the side of the anode. In these subjects, anode right stimulation induced illusory left lateral flexion and elbow joint position error towards extension (p=0.03), while anode left tended to have the opposite effect (p=0.16). The GVS had no effect on error in subjects who did not experience illusory head movement with either 1.5 mA stimulus (p=0.8) or 2.0-3.0 mA stimulus (p=0.7). This study demonstrates that the accuracy of elbow repositioning is affected by illusory changes in head position. These results support the hypothesis that the perceived position of proximal body segments is used in the planning and performance of accurate upper limb movements.

A programme of static positional stretches does not reduce hemiplegic shoulder pain or maintain shoulder range of motion - a randomized controlled trial

Objective: To evaluate the effectiveness of a programme of static positional stretches and positioning of the stroke-affected shoulder for maintaining shoulder external rotation and decreasing hemiplegic shoulder pain. Design: Randomized controlled trial with pretest and posttest design. Setting: Inpatient rehabilitation unit. Subjects: Thirty-two participants ( 17 treatment, 15 comparison) with a first time stroke who were admitted for rehabilitation. Interventions: Treatment participants completed a programme of static positional stretches of the stroke-affected shoulder twice daily and positioned the stroke-affected upper limb in an armrest support at all other times when seated. Main measures: The main outcome measures were pain-free range of motion into external rotation, pain in the stroke-affected shoulder at rest and with movement, motor recovery and functional independence. Results: All participants demonstrated a significant loss of external rotation ( P = 0.005) with no significant group differences. All participants demonstrated a significant improvement in motor recovery ( P < 0.01) and functional independence ( P < 0.01) with no significant group differences. There were no significant effects for pain. The comparison group recorded a decrease in mean pain reported with movement from admission to discharge, and the treatment group recorded an increase. Conclusions: Participation in the management programme did not result in improved outcomes. The results of this study do not support the application of the programme of static positional stretches to maintain range of motion in the shoulder. The effect of increasing pain for the treatment group requires further investigation.

Changes in head and neck position have a greater effect on elbow joint position sense in people with whiplash-associated disorders

Background: It has been shown that perception of elbow joint position is affected by changes in head and neck position. Further, people with whiplash-associated disorders (WAD) present with deficits in upper limb coordination and movement. Objectives: This study is aimed to determine whether the effect of changes in head position on elbow joint position error (JPE) is more pronounced in people with WAD, and to determine whether this is related to the participant's pain and anxiety levels. Methods: Nine people with chronic and disabling WAD and 11 healthy people participated in this experiment. The ability to reproduce a position at the elbow joint was assessed after changes in the position of the head and neck to 30 degrees, and with the head in the midline. Pain was monitored in WAD participants. Results: Absolute elbow JPE with the head in neutral was not different between WAD and control participants (P = 0.5). Changes in the head and neck position increased absolute elbow JPE in the WAD group (P < 0.05), but did not affect elbow JPE in the control group (P = 0.4). There was a connection between pain during testing and the effect of changes in head position on elbow JPE (P < 0.05). Discussion: Elbow JPE is affected by movement of the head and neck, with smaller angles of neck rotation in people with WAD than in healthy individuals. This observation may explain deficits in upper limb coordination in people with WAD, which may be due to the presence of pain or reduced range of motion in this population.

Illusory changes in head position induced by neck muscle vibration can alter the perception of elbow position

Acuity for elbow joint position sense (JPS) is reduced when head position is modified. Movement of the head is associated with biomechanical changes in the neck and shoulder musculoskeletal system, which may explain changes in elbow JPS. The present study aimed to determine whether elbow JPS is also influenced by illusory changes in head position. Simultaneous vibration of sternocleidomastoid (SCM) and the contralateral splenius was applied to 14 healthy adult human subjects. Muscle vibration or passive head rotation was introduced between presentation and reproduction of a target elbow position. Ten out of 14 subjects reported illusions consistent with lengthening of the vibrated muscles. In these 10 subjects, absolute error for elbow JPS increased with left SCM/right splenius vibration but not with right SCM/left splenius vibration. Absolute error also increased with right rotation, with a trend for increased error with left rotation. These results demonstrated that both actual and illusory changes in head position are associated with diminished acuity for elbow JPS, suggesting that the influence of head position on upper limb JPS depends, at least partially, on perceived head position.

Caractérisation tridimensionnelle de l’amplitude articulaire de l’épaule

L’épaule est l’articulation la plus mobile et la plus instable du corps humain dû à la faible quantité de contraintes osseuses et au rôle des tissus mous qui lui confèrent au moins une dizaine de degrés de liberté. La mobilité de l’épaule est un facteur de performance dans plusieurs sports. Mais son instabilité engendre des troubles musculo-squelettiques, dont les déchirures de la coiffe des rotateurs sont fréquentes et les plus handicapantes. L’évaluation de l’amplitude articulaire est un indice commun de la fonction de l’épaule, toutefois elle est souvent limitée à quelques mesures planaires pour lesquelles les degrés de liberté varient indépendamment les uns des autres. Ces valeurs utilisées dans les modèles de simulation musculo-squelettiques peuvent amener à des solutions non physiologiques. L’objectif de cette thèse était de développer des outils pour la caractérisation de la mobilité articulaire tri-dimensionnelle de l’épaule, en passant par i) fournir une méthode et son approche expérimentale pour évaluer l’amplitude articulaire tridimensionnelle de l’épaule incluant des interactions entre les degrés de liberté ; ii) proposer une représentation permettant d’interpréter les données tri-dimensionnelles obtenues; iii) présenter des amplitudes articulaires normalisées, iv) implémenter une amplitude articulaire tridimensionnelle au sein d’un modèle de simulation numérique afin de générer des mouvements sportifs optimaux plus réalistes; v) prédire des amplitudes articulaires sécuritaires et vi) des exercices de rééducation sécuritaires pour des patients ayant subi une réparation de la coiffe des rotateurs. i) Seize sujets ont été réalisé séries de mouvements d’amplitudes maximales actifs avec des combinaisons entre les différents degrés de liberté de l’épaule. Un système d’analyse du mouvement couplé à un modèle cinématique du membre supérieur a été utilisé pour estimer les cinématiques articulaires tridimensionnelles. ii) L’ensemble des orientations définies par une séquence de trois angles a été inclus dans un polyèdre non convexe représentant l’espace de mobilité articulaire prenant en compte les interactions entre les degrés de liberté. La combinaison des séries d’élévation et de rotation est recommandée pour évaluer l’amplitude articulaire complète de l’épaule. iii) Un espace de mobilité normalisé a également été défini en englobant les positions atteintes par au moins 50% des sujets et de volume moyen. iv) Cet espace moyen, définissant la mobilité physiologiques, a été utilisé au sein d’un modèle de simulation cinématique utilisé pour optimiser la technique d’un élément acrobatique de lâcher de barres réalisée par des gymnastes. Avec l’utilisation régulière de limites articulaires planaires pour contraindre la mobilité de l’épaule, seulement 17% des solutions optimales sont physiologiques. En plus, d’assurer le réalisme des solutions, notre contrainte articulaire tridimensionnelle n’a pas affecté le coût de calculs de l’optimisation. v) et vi) Les seize participants ont également réalisé des séries d’amplitudes articulaires passives et des exercices de rééducation passifs. La contrainte dans l’ensemble des muscles de la coiffe des rotateurs au cours de ces mouvements a été estimée à l’aide d’un modèle musculo-squelettique reproduisant différents types et tailles de déchirures. Des seuils de contrainte sécuritaires ont été utilisés pour distinguer les amplitudes de mouvements risquées ou non pour l’intégrité de la réparation chirurgicale. Une taille de déchirure plus grande ainsi que les déchirures affectant plusieurs muscles ont contribué à réduire l’espace de mobilité articulaire sécuritaire. Principalement les élévations gléno-humérales inférieures à 38° et supérieures à 65°, ou réalisées avec le bras maintenu en rotation interne engendrent des contraintes excessives pour la plupart des types et des tailles de blessure lors de mouvements d’abduction, de scaption ou de flexion. Cette thèse a développé une représentation innovante de la mobilité de l’épaule, qui tient compte des interactions entre les degrés de liberté. Grâce à cette représentation, l’évaluation clinique pourra être plus exhaustive et donc élargir les possibilités de diagnostiquer les troubles de l’épaule. La simulation de mouvement peut maintenant être plus réaliste. Finalement, nous avons montré l’importance de personnaliser la rééducation des patients en termes d’amplitude articulaire, puisque des exercices passifs de rééducation précoces peuvent contribuer à une re-déchirure à cause d’une contrainte trop importante qu’ils imposent aux tendons.

Variáveis objetivas e subjetivas para monitoramento de diferentes ciclos de temporada em jogadores de basquete

The present study aimed to evaluate, compare and relate load and training tiredness during a periodization cycle in basketball players. Eight professional male athletes aged 21.9 ± 3.4 years, all of whom participated in the São Paulo basketball championship, special division, took part in this study. The macrocycle analyzed encompassed 19 weeks divided into the following periods: Preparatory, Competitive I, and Competitive II (having 4, 6, and 9 weeks, respectively). The authors daily evaluated the athletes on subjective perception of tiredness and training load and monitored the athletes' upper limb power by quantifying their ability to throw a medicine ball. Athletes presented less fatigue (p <0.005) in the Preparatory period (13.71 ± 1.30) compared with the Competitive I (14.68 ± 1.51) and Competitive II (14.63 ± 1.22) periods. Their ability to throw the medicine ball decreased (p <0.005) in the Competitive period II (3.59 ± 0.30) compared with the Preparatory (3.80 ± 0.36) and Competitive I (3.86 ± 0.26) periods. Their monotony decreased (p <0.001) in the Competitive period II (1.18 ± 0.43) compared with the Preparatory (2.50 ± 2.01) and Competitive I (2.10 ± 1.61) periods. The results revealed the effectiveness of monitoring load and tiredness of athletes by means of the proposed method to assist in training organization during a macrocycle.