Figure 1.

Simplified schematic of the one degree-of-freedom apparatus used for the proprioception assessment. The motor (gray) actuates the handle (blue) in wrist flexion-extension direction. A touchscreen (semitransparent dark gray) is placed over the wrist interface, in direct line of sight, occluding the tested wrist, hand and part of the forearm from vision. With the non-assessed hand, the subject aligns the gauge (red) on the touchscreen with the perceived wrist position. During the whole assessment, the head rests on the support frame and the subject hears white noise through headphones.