A Novel Device to Evaluate the Stiffness of Ankle-Foot Orthosis Devices

[+] Author and Article Information
P. Cappa, F. Patanè, M. M. Pierro

Department of Mechanics and Aeronautics, University of Rome “La Sapienza,” Via Eudossiana 18, Rome, ItalyClinical Engineering Service, Children’s Hospital “Bambino Gesù,” Piazza San Onofrio, 4, Rome, ItalyPaediatric Neuro-Rehabilitation Division, Children’s Hospital “Bambino Gesè,” Palidoro, Rome, Italy

J Biomech Eng 125(6), 913-917 (Jan 09, 2004) (5 pages) doi:10.1115/1.1634993 History: Received October 21, 2002; Revised May 06, 2003; Online January 09, 2004
Copyright © 2003 by ASME
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Grahic Jump Location
Scheme of the AFO testing machine: two elementary rotation of abduction and flexion are represented here by angles β<0 and α<0 respectively, 0O1 is the “neutral” position of the “knee”; the rotation γ is also showed.
Grahic Jump Location
Variation of the total moment Mα2+Mβ2+Mγ2 as a function of α and β. The moment Mγ is always zeroed because the foot is free to rotate.
Grahic Jump Location
(a) Variation of the average stiffness Kα (averaged between −6° and 6°) as a function of β; (b) variation of the average stiffness Kβ (averaged between −10° and 10°) as a function of α.



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