Modelo dinámico de los movimientos de flexo extensión cervical del cuello humano, basado en pares de rodadura

Abstract

The aim of this investigation was to design a dynamic model of the cervical flexion-extension movements of the human neck. A dynamic-inverse study and an analogy with rigid solid materials and the state of the art were carried out to determine and mention anthropometric data related to physical and geometrical properties of the head. For example: mass, moment of inertia, position of occipital condyles, center of mass, turning angle and so on. From the inverse dynamics, it was necessary to get experimental data of instantaneous acceleration of the gravity center of the head that is why it was necessary to record a video at 30 frames per second (FPS). This recording shows a person in motion cervical flexion- extension in a sagittal plane during a given time period. By analyzing the movements, the head trajectory coordinates (x,y) according to the time could be gotten. Later, we made a filtration process for rectification of experimental data in order to eliminate the noise in the data. Finally, we carried out trajectory settings and the calculation of its derivatives (instantaneous velocity and acceleration). The calculations of reaction forces and momentum generating in the occipital condyles for several movement cycles of cervical flexion extension have been carried by Matlab algorithms.