[Differences in biomechanical parameters during sit to stand transfer between elderly with and without history of frequent falls]. / Diferencias biomecánicas durante la transferencia de sedente a bípedo entre adultos mayores con y sin historia de caídas frecuentes.

INTRODUCTION: The phenomenon of frequent falls (FF) is a health problem in the older population, and is a reason why tools need to be designed for the objective assessment of the risk of FF. In this sense the use of biomechanical parameters could be of use in designing these. The aim of this work was to describe the biomechanical differences registered during a sit to stand transfer (STS) between subjects with and without a history of frequent falls. MATERIAL AND METHOD: A sample of sixty voluntary older adults were assessed, divided in two groups of thirty subjects. The first group was composed of older adults without history of frequent falls (WoHFF) and the other group with history of frequent falls (WHFF). In both groups the velocity of the mass centre, the anterior flexion of the trunk, the joint and support moments of the lower extremity and the time of execution during the TSB was assessed. RESULTS: The subjects WHFF generate a slower vertical velocity (P<0.001), lower slope (P<0.001), greater anterior trunk flexion (P<0.0001), lower support moment (P=0.001) and took longer in executing the STS (P=0.0001) than the group WoHFF. CONCLUSIONS: Differences exist in the biomechanical parameters registered during the STS between the elderly WHFF and WoHFF. The results indicate that the function of the hip extensor muscles could have an important role in the execution of the STS in subjects WHFF. The biomechanical parameters assessed during the STS should be considered as useful tools to distinguish between subjects WHFF and WoHFF, and should be considered in the design of tools to determine the risk of frequent falls.

[Differences in momentum development when standing up from a chair between elderly with and without frequent falls history]. / Diferencias en el desarrollo de momentum al levantarse desde una silla en adultos mayores con y sin historia de caídas frecuentes.

INTRODUCTION: The momentum of the upper body (UB) during transfer sit-to-stand (STS) could be sensitive to the deterioration of dynamic postural control, and also the risk of falls. The aim of this study is to quantify the differences in the momentum development on UB during the STS in a sample of fall and no-fall elderly subjects. MATERIAL AND MEHODS: The sample consisted of twenty three voluntary elderly subjects (n=23), six elderly adults with antecedents of frequent falls (more than two within a year period) and seventeen without histories of frequent falls. Through a motion analysis system we registered the kinematics of UB during STS, from which we calculated the momentum of UB. The determined analysis variables were: the maximum values of the vertical (P(V)M) and horizontal (P(H)M) lineal momenta, the minimum (L(Max)) and maximum (L(Min)) values of the angular momentum and maximum trunk flexion (thetaM(UB)). RESULTS: No difference was observed in P(H)M, L(Max) and L(Min) (P>0.05) between both groups. However, a significant difference was found for the variable P(V)M (P=0.03) and thetaM(UB) (P=0.03) between both groups. CONCLUSIONS: We can conclude that, for the sample studied, the frequent fall condition relates to a smaller capacity to develop vertical momentum and increase flexion of the upper body.

Diferencias biomecánicas durante la transferencia de sedente a bípedo entre adultos mayores con y sin historia de caídas frecuentes / Differences in biomechanical parameters during sit to stand transfer between elderly with and without history of frequent falls

Introducción. El fenómenos de caídas frecuentes (CF) es un problema de salud para la población adulta mayor, por lo cual el diseño de herramientas objetivas en la valoración del riesgo de CF es necesario, en este sentido la utilización de parámetros biomecánicos puede ser de utilidad en el diseño de estas. El objetivo de este trabajo estuvo en describir las diferencias biomecánicas registradas durante la transferencia de sedente a bípedo (TSB) entre sujetos con y sin historia de caídas frecuentes. Material y método. Se evaluó una muestra de 60 sujetos adultos mayores, divididos en 2 grupos de 30. El primero de ellos formado por sujetos sin historia de caídas frecuentes (SHCF) y el otro con historia de caídas frecuentes (CHCF). En ambos grupos se evaluó la velocidad del centro de masa, la magnitud de flexión anterior de tronco, los momentos articulares y de soporte de la extremidad inferior y el tiempo de ejecución durante la TSB. Resultados. Los sujetos CHCF generaron menor velocidad vertical (p<0,001), menor pendiente (p<0,001), mayor inclinaron de tronco (p<0,0001), menor momento de soporte (p=0,001) y tardaron más en ejecutar la TSB (p=0,0001) que el grupo SHCF. Conclusiones. Existen diferencias en los parámetros biomecánicos registrados durante la TSB entre ancianos CHCF y SHCF. Los resultados indican que la función de los músculos extensores de cadera podrían tener un importante rol en la ejecución de la TSB en sujetos CHCF. Las variables biomecánicas registradas durante la TSB deben ser consideradas como herramientas útiles para diferenciar entre sujetos CHCF y SHCF, pudiendo ser consideradas en el diseño de herramientas para determinar el riesgo de caídas frecuentes(AU)

Introduction. The phenomenon of frequent falls (FF) is a health problem in the older population, and is a reason why tools need to be designed for the objective assessment of the risk of FF. In this sense the use of biomechanical parameters could be of use in designing these. The aim of this work was to describe the biomechanical differences registered during a sit to stand transfer (STS) between subjects with and without a history of frequent falls. Material and method. A sample of sixty voluntary older adults were assessed, divided in two groups of thirty subjects. The first group was composed of older adults without history of frequent falls (WoHFF) and the other group with history of frequent falls (WHFF). In both groups the velocity of the mass centre, the anterior flexion of the trunk, the joint and support moments of the lower extremity and the time of execution during the TSB was assessed. Results. The subjects WHFF generate a slower vertical velocity (P<0.001), lower slope (P<0.001), greater anterior trunk flexion (P<0.0001), lower support moment (P=0.001) and took longer in executing the STS (P=0.0001) than the group WoHFF. Conclusions. Differences exist in the biomechanical parameters registered during the STS between the elderly WHFF and WoHFF. The results indicate that the function of the hip extensor muscles could have an important role in the execution of the STS in subjects WHFF. The biomechanical parameters assessed during the STS should be considered as useful tools to distinguish between subjects WHFF and WoHFF, and should be considered in the design of tools to determine the risk of frequent falls(AU)

Diferencias en el desarrollo de momentum al levantarse desde una silla en adultos mayores con y sin historia de caídas frecuentes / Differences in the momentum development during transfers sit to stand between fall and no fall elderly

Introducción El momentum del cuerpo superior (CS) que comprende los segmentos de tronco, cabeza y extremidades superiores, durante la transferencia de sedestación a bipedestación (STS [sit-to-stand]) podría ser sensible al deterioro del control postural dinámico y con ello al riesgo de caídas. El objetivo de este estudio fue cuantificar las diferencias en el desarrollo del momentum sobre el CS durante el STS en una muestra de adultos mayores con y sin historia de caídas frecuentes (SHCF).Material y métodos La muestra fue de veintitrés adultos mayores voluntarios (n=23), siete con antecedentes de caídas frecuentes (más de dos caídas en el ultimo año) y dieciséis sin dicho antecedente.Material y métodos Mediante un sistema de análisis de movimiento se registró la cinemática del CS durante el STS, a partir de la cual se calculó el momentum del CS. Como variables de análisis se determinaron los valores máximos del momentum lineal vertical (PVM) y horizontal (PHM), como también los máximos (LMax) y mínimos (LMin) del momentum angular, además de la máxima flexión de tronco (θMCS).Resultados No se observaron diferencias significativas en las variables de PHM, LMax y LMin (p>0,05). Existió diferencia significativa en PVM (p=0,03) y en θMCS (p=0,03) entre ambos grupos.Conclusiones Para la muestra evaluada, una característica de los sujetos con antecedentes de caídas frecuentes fue la pobre capacidad de generar momentum en el sentido vertical y un aumento de la flexión del cuerpo superior, en comparación con los sujetos SHCF (AU)

Introduction The momentum of the upper body (UB) during transfer sit-to-stand (STS) could be sensitive to the deterioration of dynamic postural control, and also the risk of falls. The aim of this study is to quantify the differences in the momentum development on UB during the STS in a sample of fall and no-fall elderly subjects.Material and mehods The sample consisted of twenty three voluntary elderly subjects (n=23), six elderly adults with antecedents of frequent falls (more than two within a year period) and seventeen without histories of frequent falls. Material and mehodsThrough a motion analysis system we registered the kinematics of UB during STS, from which we calculated the momentum of UB. The determined analysis variables were: the maximum values of the vertical (PVM) and horizontal (PHM) lineal momenta, the minimum (LMax) and maximum (LMin) values of the angular momentum and maximum trunk flexion (θMUB).Results No difference was observed in PHM, LMax and LMin (P>0.05) between both groups. However, a significant difference was found for the variable PVM (P=0.03) and θMUB (P=0.03) between both groups. ConclusionsWe can conclude that, for the sample studied, the frequent fall condition relates to a smaller capacity to develop vertical momentum and increase flexion of the upper body (AU)