In virtually unloaded conditions, the tibiotalar (ankle) joint behaves as a single degree-of-freedom system, and two fibres within the calcaneal-fibular and tibio-calcaneal liga-ments remain nearly isometric throughout the flexion arc [1]. A relevant theoretical model also showed that three articular surfaces and two ligaments act together as a mechanism to control the passive kinematics [2]. Two equivalent spatial parallel mechanisms were formulated, with ligament fibres assumed isometric and articulating surfaces assumed rigid, either as three sphere-plane contacts, or as a single spherical pair. Predicted and measured motion in three specimens compared fairly well. Important enhancement of this previous work is here presented, with more accurate experimental data, more anatomical model surfaces, and a more robust mathematical model.
A new spatial mechanism model for the kinematics analysis of the tibiotalar joint / FRANCI R.; PARENTI CASTELLI V.; BELVEDERE C.; LEARDINI A.. - STAMPA. - (2008), pp. 1-1. (Intervento presentato al convegno i-FAB 2008,1st International Foot and Ankle Biomechanics Conference tenutosi a Bologna, Italia nel 4-6 Septembre 2008).
A new spatial mechanism model for the kinematics analysis of the tibiotalar joint
FRANCI, RICCARDO;PARENTI CASTELLI, VINCENZO;BELVEDERE, CLAUDIO;LEARDINI, ALBERTO
2008
Abstract
In virtually unloaded conditions, the tibiotalar (ankle) joint behaves as a single degree-of-freedom system, and two fibres within the calcaneal-fibular and tibio-calcaneal liga-ments remain nearly isometric throughout the flexion arc [1]. A relevant theoretical model also showed that three articular surfaces and two ligaments act together as a mechanism to control the passive kinematics [2]. Two equivalent spatial parallel mechanisms were formulated, with ligament fibres assumed isometric and articulating surfaces assumed rigid, either as three sphere-plane contacts, or as a single spherical pair. Predicted and measured motion in three specimens compared fairly well. Important enhancement of this previous work is here presented, with more accurate experimental data, more anatomical model surfaces, and a more robust mathematical model.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
