[Coordination patterns assessed by a continuous measure of joints coupling during upper limb repetitive movements].
We analyzed the coordination patterns between elbow, shoulder and trunk in a motor task consisting of reaching out, picking up a cylinder, and transporting it back by using the Dynamical Systems Theory and calculating the continuous relative phase (CRP), a continuous measure of the coupling between two interacting joints. We used an optoelectronic motion analysis system consisting of eight infra-red ray cameras to detect the movements of nine skin-mounted markers. We calculated the root square of the adjusted coefficient of determination, the coefficient of multiple correlation (CMC), in order to investigate the repeatability of the joints coordination. The data confirm that the CNS establishes both synergic (i.e. coupling between shoulder and trunk on the frontal plane) and hierarchical (i.e. coupling between elbow-shoulder-trunk on the horizontal plane) relationships among the available degrees of freedom to overcome the complexity due to motor redundancy. The present study describes a method to investigate the organization of the kinematic degrees of freedom during upper limb multi-joint motor tasks that can be useful to assess upper limb repetitive movements.
Draicchio
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ISPESL, Dipartimento di Medicina del Lavoro, Laboratorio di Fisiologia, Ergonomia, Postura e Movimento, Roma, Italy. francesco.draicchio@ispesl.it
Silvetti
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A
Ranavolo
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A
Iavicoli
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S
D001696:Biomechanical Phenomena; D004551:Elbow Joint / Q000502:physiology*; D006801:Humans; D012785:Shoulder Joint / Q000502:physiology*