ARTIFACTS ON ANKLE 3D KINEMATICS RESULTING FROM MOTION OF SHANK LATERAL BAR IN MOTION ANALYSIS PROTOCOLS

Lateral shank bar is used by several motion analysis protocols for the definition of the anatomical reference frame of the shank. In addition to critical static alignment, the lateral bar can be affected by relevant motion relative to the underlying bony segment during walking, and this motion can result into a significant error superimposed to the relevant resulting ankle kinematics. The present study quantified the propagation of lateral bar motion to relevant 3D ankle kinematics during walking in normal subjects. Lateral bar motion critically affects particularly ankle internal-external rotation and kinematic values at heel-strike.