During gait with crutches

The goal of this study was to develop a three-dimensional kinematic and kinetic model of the right upper extremity and a Lofstrand crutch in order to analyze joint displacements and loads during crutch-assisted gait. A Lofstrand crutch was instrumented with a six-component load cell to measure forces and moments at the crutch tip. The crutch and the right upper extremity of a subject were instrumented with markers to obtain kinematic data. A biomechanical model based on rigid bodies was implemented in biomechanical analysis software. To demonstrate the functionality of the model, a pilot test was conducted on one healthy individual during Lofstrand crutch-assisted gait. The shoulder extended during the support phase and flexed in the swing phase, the elbow flexed during the swing, and the wrist remained in extension throughout the cycle. In the shoulder and elbow joints, the predominant reaction forces were upward, whereas the internal force moments were flexion and extension, respectively. This tool will be useful when it comes to identifying risk factors for joint pathology associated with pattern gait, aid design or crutch overuse.Peer Reviewe

Cambios en la cinemática articular tras entrenamiento de la marcha con exoesqueleto robótico ambulatorio

En los últimos años se está investigando las prestaciones de los exoesqueletos robóticos ambulatorios para la rehabilitación de la capacidad de marcha de pacientes con patologías neurológicas tales como lesión medular o accidente cerebro-vascular. Si bien existen ciertas evidencias de su impacto positivo en la función de marcha, los mecanismos responsables de las mejoras todavía no han sido correctamente descritos.La utilización de un exoesqueleto para la rehabilitación se basa en la imposición de patrones articulares normativos durante la marcha, con el objetivo de que la repetición intensiva y controlada de estos patrones durante la marcha resulte en el aprendizaje por parte del paciente de estos patrones. No obstante no se conoce el efecto inmediato sobre la cinemática del paciente de la utilización terapéutica de un exoesqueleto.En estre trabajo se presenta el análisis de la cinemática de la cadera, rodilla y tobillo de un paciente con lesión medular antes y después de una sesión de tratamiento de rehabilitación de la marcha con exoesqueleto ambulatorio.Del-Ama, A.; Megía García-Carpintero, Á.; Lozano-Berrio, V.; Pérez-Rizo, E. (2020). Cambios en la cinemática articular tras entrenamiento de la marcha con exoesqueleto robótico ambulatorio. Editorial Universitat Politècnica de València. https://doi.org/10.4995/CEABioIng.2019.10065OC

Instrumentation and biomechanical model for kinematic and kinetic analysis of upper limbs during gait with crutches

[EN] The goal of this study was to develop a three-dimensional kinematic and kinetic model of the right upper extremity and a Lofstrand crutch in order to analyze joint displacements and loads during crutch-assisted gait. A Lofstrand crutch was instrumented with a six-component load cell to measure forces and moments at the crutch tip. The crutch and the right upper extremity of a subject were instrumented with markers to obtain kinematic data. A biomechanical model based on rigid bodies was implemented in biomechanical analysis software. To demonstrate the functionality of the model, a pilot test was conducted on one healthy individual during Lofstrand crutch-assisted gait. The shoulder extended during the support phase and flexed in the swing phase, the elbow flexed during the swing, and the wrist remained in extension throughout the cycle. In the shoulder and elbow joints, the predominant reaction forces were upward, whereas the internal force moments were flexion and extension, respectively. This tool will be useful when it comes to identifying risk factors for joint pathology associated with pattern gait, aid design or crutch overuse.This work was supported by a grant from the Castile-La Mancha Social & Health Foundation (Fundación Sociosanitaria de Castilla la Mancha) (PI2010/50). The research for this manuscript was partially funded by a CONSOLIDER INGENIO grant from the Spanish Ministry of Science and Innovation under its HYPER project (Hybrid NeuroProsthetic and NeuroRobotic Devices for Functional Compensation and Rehabilitation of Motor Disorders, CSD2009- 00067). We should like to thank Ana de los Reyes, Antonio del Ama, Beatriz Crespo, Fernando Trincado, Iris Dimbwadyo, Vicente Lozano, and Soraya Pérez for their contributions to this study.Pérez-Rizo, E.; Solís-Mozos, M.; Belda Lois, JM.; Page Del Pozo, AF.; Taylor, J.; Pons, JL.; Gil-Agudo, Á. (2013). Instrumentation and biomechanical model for kinematic and kinetic analysis of upper limbs during gait with crutches. Journal of Accessibility and Design for All. 3(2):135-156. https://doi.org/10.17411/jacces.v3i2.16S1351563

Point-Mass Biomechanical Model of the Upper Extremity During Lofstrand Crutch-Assisted Gait

We propose a point-mass biomechanical model to estimate the forces and moments supported by the upper extremity during Lofstrand crutch-assisted gait. This model is based on the Newtonian classical mechanics and the angular momentum theorem. The system arm-crutch is divided into three segments: 1) crutch, 2) wrist-elbow, and 3) elbow-shoulder. The theoretical model was experimentally validated with a disabled person with spinal cord injury. Two crutch-assisted gait patterns have been chosen to carry out the experimental validation: two-point reciprocal gait and swing-through gait. Six position markers (three placed on the arm and three placed on the crutch) and two force sensors (placed on the crutch) were used in experiments for testing the model. The results were compared with a distributed-mass model based on studies previously published, concluding that the relative mean difference between models is less than 3% Body Weight and 1% Body Weight times Height when forces and moments are estimated, respectively. Some advantages of using a point-mass model are summarized: simple formulation, easy to understand; require less numerical calculation reducing the computational cost; requires less position markers placed on the subject, increasing therefore the comfort of the subject

Análisis biomecánico para confirmar el diagnóstico en neurorrehabilitación

[ES] En los pacientes con lesión medular cervical (LMC) se ve comprometida en mayor o menor medida la fuerza de las extremidades superiores, lo que se traduce en dependencia para las AVDs. Si la lesión es incompleta, puede preservarse la capacidad de marcha. En este contexto, resulta difícil realizar un diagnóstico clínico correcto y los equipos de fotogrametría constituyen una herramienta de gran valor para objetivar las secuelas motoras. El objetivo es presentar la metodología biomecánica de miembros superiores e inferiores aplicada a un caso de estudio. Se trata de un paciente varón de 61 años que padeció una LMC incompleta de etiología traumática que, previamente, había sufrido un TCE. Mediante fotogrametría se analizaron los recorridos articulares de la cadera, rodilla y tobillo durante los ciclos de la marcha y del hombro, codo y muñeca, así como una serie de índices cinemáticos descriptores del movimiento del miembro superior. Se obtuvo un patrón de marcha muy simétrico en ambos miembros inferiores. Sin embargo, la funcionalidad global y los índices de destreza en ambos miembros superiores presentaron una marcada asimetría entre ellos. Las herramientas biomecánicas evidencian aspectos del control motor no fácilmente visibles con los tests clínicos y que perfeccionan el diagnóstico de los casos complejos.[EN] In cervical spinal cord injured (SCI) patients, upper limbs strength is affected to a greater or lesser extent, producing dependence on the execution of ADLs. If the lesion is incomplete, the gait ability can be preserved. In this context, it is difficult to make a correct clinical diagnosis and the photogrammetry equipments constitute a tool of great value to determine with objectivity motor sequelae. The objective is to present the biomechanics methodology of upper and lower limbs applied to a case study. It is a 61- year-old male patient who suffered an incomplete SCI of traumatic etiology that had previously suffered a traumatic brain injury. Through photogrammetry, the range of motion of the hip, knee and ankle joints were analyzed during the cycles of the gait and the shoulder, elbow and wrist joints, as well as a series of kinematic indices describing the ability and dexterity of the upper limb movement. A very symmetrical gait pattern was obtained in both lower limbs. However, overall functionality and skill indices in both upper limbs present a high asymmetry between them. Biomechanical tools demonstrate aspects of motor control not easily visible with clinical tests and perfect diagnosis of complex casesDe Los Reyes Guzmán, A.; López-Dolado, E.; Pérez-Rizo, E.; Lozano-Berrio, V.; Gil-Agudo, A.; Del Ama Espinosa, A. (2019). Análisis biomecánico para confirmar el diagnóstico en neurorrehabilitación. En 11º Simposio CEA de Bioingeniería. Editorial Universitat Politècnica de València. 49-63. https://doi.org/10.4995/CEABioIng.2019.10045OCS496

Gait kinematic analysis in patients with a mild form of central cord syndrome

<p>Abstract</p> <p>Background</p> <p>Central cord syndrome (CCS) is considered the most common incomplete spinal cord injury (SCI). Independent ambulation was achieved in 87-97% in young patients with CCS but no gait analysis studies have been reported before in such pathology. The aim of this study was to analyze the gait characteristics of subjects with CCS and to compare the findings with a healthy age, sex and anthropomorphically matched control group (CG), walking both at a self-selected speed and at the same speed.</p> <p>Methods</p> <p>Twelve CCS patients and a CG of twenty subjects were analyzed. Kinematic data were obtained using a three-dimensional motion analysis system with two scanner units. The CG were asked to walk at two different speeds, at a self-selected speed and at a slower one, similar to the mean gait speed previously registered in the CCS patient group. Temporal, spatial variables and kinematic variables (maximum and minimum lower limb joint angles throughout the gait cycle in each plane, along with the gait cycle instants of occurrence and the joint range of motion - ROM) were compared between the two groups walking at similar speeds.</p> <p>Results</p> <p>The kinematic parameters were compared when both groups walked at a similar speed, given that there was a significant difference in the self-selected speeds (p < 0.05). Hip abduction and knee flexion at initial contact, as well as minimal knee flexion at stance, were larger in the CCS group (p < 0.05). However, the range of knee and ankle motion in the sagittal plane was greater in the CG group (p < 0.05). The maximal ankle plantar-flexion values in stance phase and at toe off were larger in the CG (p < 0.05).</p> <p>Conclusions</p> <p>The gait pattern of CCS patients showed a decrease of knee and ankle sagittal ROM during level walking and an increase in hip abduction to increase base of support. The findings of this study help to improve the understanding how CCS affects gait changes in the lower limbs.</p

Caracterización genética de aislamientos de SARS-CoV-2 en las diferentes etapas pandémicas de COVID-19 en Cuba

Introducción: El desarrollo de vacunas seguras y eficaces contra el SARS-CoV-2 supuso un enorme reto para enfrentar la pandemia de la COVID-19. La aparición de nuevas variantes del SARS-CoV-2 representa un reto en la evaluación de la efectividad de las vacunas, diferentes candidatos vacunales y terapéuticos desarrollados por la comunidad científica. Objetivos: Caracterizar la diversidad genética de aislamientos virales cubanos en el periodo comprendido entre junio de 2020 y diciembre de 2022. Métodos: Se obtuvo el ARN de SARS-CoV-2 de 27 aislamientos a partir de sobrenadante de cultivo celular y se secuenció el gen S. Las secuencias generadas se emplearon para la identificación y posterior caracterización molecular de las variantes genéticas del virus mediante análisis filogenético y el uso de las herramientas disponibles en la base de datos GISEAD. Resultados: Las variantes detectadas en los aislamientos cubanos de SARS-CoV-2 estudiados se correspondieron a las identificadas en los estudios de vigilancia genómica realizados en las diferentes etapas pandémicas de la COVID-19 en Cuba. El 33,3 % de los aislamientos secuenciados correspondieron a los diferentes linajes de la variante Ómicron, seguido de la variante Beta B 1.351 (29,6 %), otros linajes de SARS-CoV-2 (25,9 %), Alfa B 1.1.7 (7,4 %) y Delta B.1.575 (3,7 %). Se detectó la mutación D614G en todos los aislamientos de SARS-CoV-2 estudiados. Conclusiones: La caracterización molecular de los aislamientos cubanos de SARS-CoV-2 tiene una elevada diversidad genética. Posibilita evaluar in vitro e in vivo los candidatos vacunales y agentes terapéuticos desarrollados por la industria biofarmacéutica cubana

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Descripción: El curso International Business es un curso de línea de carrera de Administración y Negocios Internacionales de carácter teórico-práctico dirigido a los estudiantes del tercer ciclo con el objetivo de brindar una visión global y actual del entorno de los negocios el cual responde a un enfoque moderno de la administración estratégica de las empresas. Propósito: El curso International Business es relevante para los estudiantes porque busca desarrollar las capacidades que le permitirán al futuro profesional formular proyectos internacionales de negocios en un contexto global según las nuevas tendencias de Geomundo teniendo en cuenta los aspectos culturales, sociales, económicos, políticos, legales, jurídicos y financieros del dinámico entorno internacional los cuales impactan en el desempeño de las organizaciones donde ejercerá laboralmente, teniendo como prerrequisito el curso 1Introduction to International Business. El curso contribuye directamente al desarrollo de la competencia específica de Formulación de Proyectos Internacionales del nivel 1

Kinematic analysis of the daily activity of drinking from a glass in a population with cervical spinal cord injury

Background Three-dimensional kinematic analysis equipment is a valuable instrument for studying the execution of movement during functional activities of the upper limbs. The aim of this study was to analyze the kinematic differences in the execution of a daily activity such as drinking from a glass between two groups of patients with tetraplegia and a control group. Methods A total of 24 people were separated into three groups for analysis: 8 subjects with metameric level C6 tetraplegia, 8 subjects with metameric level C7 tetraplegia and 8 control subjects (CG). A set of active markers that emit infrared light were positioned on the upper limb. Two scanning units were used to record the sessions. The activity of drinking from a glass was broken down into a series of clearly identifiable phases to facilitate analysis. Movement times, velocities, and the joint angles of the shoulder, elbow and wrist in the three spatial planes were the variables analyzed. Results The most relevant differences between the three groups were in the wrist. Wrist palmar flexion during the back transport phase was greater in the patients with C6 and C7 tetraplegia than in the CG, whereas the highest wrist dorsal flexion values were in forward transport in the subjects with C6 or C7 tetraplegia, who required complete activation of the tenodesis effect to complete grasping. Conclusions A detailed description was made of the three-dimensional kinematic analysis of the task of drinking from a glass in healthy subjects and in two groups of patients with tetraplegia. This was a useful application of kinematic analysis of upper limb movement in a clinical setting. Better knowledge of the execution of this movement in each of these groups allows therapeutic recommendations to be specifically adapted to the functional deficit present. This information can be useful in designing wearable robots to compensate the performance of AVD, such as drinking, in people with cervical SCI

Consenso Mexicano para el Tratamiento de la Hepatitis C

El objetivo del Consenso Mexicano para el Tratamiento de la Hepatitis C fue el de desarrollar un documento como guía en la práctica clínica con aplicabilidad en México. Se tomó en cuenta la opinión de expertos en el tema con especialidad en: gastroenterología, infectología y hepatología. Se realizó una revisión de la bibliografía en MEDLINE, EMBASE y CENTRAL mediante palabras claves referentes al tratamiento de la hepatitis C. Posteriormente se evaluó la calidad de la evidencia mediante el sistema GRADE y se redactaron enunciados, los cuales fueron sometidos a voto mediante un sistema modificado Delphi, y posteriormente se realizó revisión y corrección de los enunciados por un panel de 34 votantes. Finalmente se clasificó el nivel de acuerdo para cada oración. Esta guía busca dar recomendaciones con énfasis en los nuevos antivirales de acción directa y de esta manera facilitar su uso en la práctica clínica. Cada caso debe ser individualizado según sus comorbilidades y el manejo de estos pacientes siempre debe ser multidisciplinario. Abstract The aim of the Mexican Consensus on the Treatment of Hepatitis C was to develop clinical practice guidelines applicable to Mexico. The expert opinion of specialists in the following areas was taken into account: gastroenterology, infectious diseases, and hepatology. A search of the medical literature was carried out on the MEDLINE, EMBASE, and CENTRAL databases through keywords related to hepatitis C treatment. The quality of evidence was subsequently evaluated using the GRADE system and the consensus statements were formulated. The statements were then voted upon, using the modified Delphi system, and reviewed and corrected by a panel of 34 voting participants. Finally, the level of agreement was classified for each statement. The present guidelines provide recommendations with an emphasis on the new direct-acting antivirals, to facilitate their use in clinical practice. Each case must be individualized according to the comorbidities involved and patient management must always be multidisciplinary