Fig. 1

Motor-controlled isokinetic custom apparatus to measure the extension stiffness in wrist joint. A Configuration of the experimental setup. B Appearance of the device. Left side: Overall picture of the equipment and positioning of the forearm and hand compartment. The hands were fixed with all fingers extended to reflect not only the spasticity of wrist flexors but also that of the extrinsic finger flexors. Right side: Lateral view of the motor and encoder compartment. C Top view of the hand compartment: The force sensor with a sliding system and hand plate. D Detailed view of the motor and encoder compartment. The axis of rotation (dotted arrow) was aligned with the axis of the wrist joint (solid circle in C)