AN INTEGRATED PROCEDURE TO ASSESS KNEE-JOINT KINEMATICS AND KINETICS DURING GAIT USING AN OPTOELECTRIC SYSTEM AND STANDARDIZED X-RAYS

This paper describes a 3-D gait analysis system, which combines optoel ectric motion tracking and a standardized X-ray procedure, to calculat e the net knee-joint forces and moments of a normal subject group duri ng walking. The optoelectric system collects kinematic data from infra -red LED markers placed at selected skin surface locations and project ing probes attached to the lower limb. A standardized X-ray procedure is used to move surface markers into their designated bony landmarks b ased on individual bone structure, which reduces the error caused by u ncertainty of skin-surface marker locations. Based on moved-in marker information, different joint coordinate systems are proposed for kinem atic and kinetic analysis of the knee joint. Normalized data of knee a ngles, net reaction forces and net moments from 35 young, normal subje cts are presented.