Article

The current study aimed to quantify the soft tissue artifacts of selected markers
on the thigh and shank, and their effects on the calculated joint center
translations, angles and moments of the knee during sit-to-stand. Ten patients
with total knee replacements rose from a chair under simultaneous surveillance of
a motion capture system, a force-plate and a fluoroscopy system. The "true" poses
of the thigh and shank were defined by those of the femoral and tibial components
obtained using a three-dimensional fluoroscopy method. The soft tissue artifacts
of the skin markers were calculated as their movement relative to the underlying
prosthesis components. The joint center translations, angles and moments at the
knee were also calculated separately using skin markers and the registered
prosthesis poses. Considerable soft tissue artifacts were found, leading to
significantly underestimated flexion and internal rotation angles, and extensor
moments, but overestimated joint center translations and adduction. The current
study provides accurate data of the kinematics and kinetics of total knee
replacements during sit-to-stand. The effects of soft tissue artifacts on the
calculated joint center translations, angles and moments were also quantified for
the first time in the literature. The results may help in developing guidelines
for using skin markers and in establishing databases in the biomechanical
assessment of sit-to-stand in patients with total knee replacements.
CI - Copyright (c) 2011. Published by Elsevier B.V.

Langue : ANGLAIS