Dynamic stiffness measurement and the control of movement

Experimental characterization of muscle, joint, and limb dynamic stiffness is essential for understanding how the nervous system normally controls movement and posture, and for devising control systems using functional neuromuscular stimulation (FNS) for restoring these behaviors in paralyzed individuals. Dynamic stiffness arises from a number of different sources, many of which nonlinear. The authors discuss the impact that definition of dynamic stiffness and associated experimental techniques have on its physiological interpretation and functional significance