%0 Journal Article
	%A Azadeh Rouhandeh and  Chris Joslin and  Zhen Qu and  Yuu Ono
	%D 2014
	%J International Journal of Bioengineering and Life Sciences
	%B World Academy of Science, Engineering and Technology
	%I Open Science Index 90, 2014
	%T Quantification of Soft Tissue Artefacts Using Motion Capture Data and Ultrasound Depth Measurements
	%U https://publications.waset.org/pdf/9998527
	%V 90
	%X The centre of rotation of the hip joint is needed for an
accurate simulation of the joint performance in many applications
such as pre-operative planning simulation, human gait analysis, and
hip joint disorders. In human movement analysis, the hip joint center
can be estimated using a functional method based on the relative
motion of the femur to pelvis measured using reflective markers
attached to the skin surface. The principal source of errors in
estimation of hip joint centre location using functional methods is
soft tissue artefacts due to the relative motion between the markers
and bone. One of the main objectives in human movement analysis is
the assessment of soft tissue artefact as the accuracy of functional
methods depends upon it. Various studies have described the
movement of soft tissue artefact invasively, such as intra-cortical
pins, external fixators, percutaneous skeletal trackers, and Roentgen
photogrammetry. The goal of this study is to present a non-invasive
method to assess the displacements of the markers relative to the
underlying bone using optical motion capture data and tissue
thickness from ultrasound measurements during flexion, extension,
and abduction (all with knee extended) of the hip joint. Results show
that the artefact skin marker displacements are non-linear and larger
in areas closer to the hip joint. Also marker displacements are
dependent on the movement type and relatively larger in abduction
movement. The quantification of soft tissue artefacts can be used as a
basis for a correction procedure for hip joint kinematics.

	%P 334 - 338