Bayesian inverse kinematics vs. least-squares inverse kinematics in estimates of planar postures and rotations in the absence of soft tissue artifact

The purpose of this study was to quantify the effect of soft tissue artifact during three-dimensional motion capture and assess the effectiveness of an optimization method to reduce this effect. Four subjects were captured performing upper-arm internal-external rotation with retro-reflective marker sets attached to their upper extremities. A mechanical arm, with the same marker set attached, replicated the tasks human subjects performed. Artificial sinusoidal noise was then added to the recorded mechanical arm data to simulate soft tissue artifact. All data were processed by an optimization model. The result from both human and mechanical arm kinematic data demonstrates that soft tissue artifact can be reduced by an optimization model, although this error cannot be successfully eliminated. The soft tissue artifact from human subjects and the simulated soft tissue artifact from artificial sinusoidal noise were demonstrated to be considerably different. It was therefore concluded that the kinematic noise caused by skin movement artifact during upper-arm internal-external rotation does not follow a sinusoidal pattern and cannot be effectively eliminated by an optimization model.

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Using MR Imaging and X-Ray Fluoroscopy to Quantify the Effects of Soft-Tissue Artifact on Measurement of Knee-Joint Kinematics

ASME 2009 Summer Bioengineering Conference, Parts A and B ◽

10.1115/sbc2009-206551 ◽

2009 ◽

Author(s):

Massoud Akbarshahi ◽

Justin W. Fernandez ◽

Anthony Schache ◽

Richard Baker ◽

Marcus G. Pandy

Keyword(s):

Soft Tissue ◽

Knee Joint ◽

Soft Tissues ◽

Surgical Techniques ◽

Joint Kinematics ◽

Segmental Motion ◽

Coordinate Systems ◽

Knee Joint Kinematics ◽

Soft Tissue Artifact

The ability to accurately measure joint kinematics in vivo is of critical importance to researchers in the field of biomechanics [1]. Applications range from the quantitative evaluation of different surgical techniques, treatment methods and/or implant designs, to the development of computer-based models capable of simulating normal and pathological musculoskeletal conditions [1,2]. Currently, non-invasive marker-based three dimensional (3D) motion analysis is the most commonly used method for quantitative assessment of normal and pathological locomotion. The accuracy of this technique is influenced by movement of the soft tissues relative to the underlying bones, which causes inaccuracies in the determination of segmental anatomical coordinate systems and tracking of segmental motion. The purpose of this study was to quantify the errors in the measurement of knee-joint kinematics due solely to soft-tissue artifact (STA) in healthy subjects. To facilitate valid inter-subject comparisons of the kinematic data, relevant anatomical coordinate systems were defined using 3D bone models generated from magnetic resonance imaging (MRI).

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Validation of a new method for bone motion measurement by soft-tissue artifact compensation through spatial interpolation

2015 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS) ◽

10.1109/iros.2015.7353733 ◽

2015 ◽

Author(s):

Simon Bouvel ◽

Viviane Pasqui ◽

Guillaume Morel

Keyword(s):

Soft Tissue ◽

Spatial Interpolation ◽

New Method ◽

Motion Measurement ◽

Soft Tissue Artifact

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Knee joint kinematics and kinetics during the hop and cut after soft tissue artifact suppression: Time to reconsider ACL injury mechanisms?

Journal of Biomechanics ◽

10.1016/j.jbiomech.2017.06.049 ◽

2017 ◽

Vol 62 ◽

pp. 132-139 ◽

Cited By ~ 4

Author(s):

Kenneth B. Smale ◽

Brigitte M. Potvin ◽

Mohammad S. Shourijeh ◽

Daniel L. Benoit

Keyword(s):

Soft Tissue ◽

Knee Joint ◽

Acl Injury ◽

Joint Kinematics ◽

Injury Mechanisms ◽

Knee Joint Kinematics ◽

Artifact Suppression ◽

Soft Tissue Artifact ◽

Kinematics And Kinetics ◽

Suppression Time

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A comparison of three-dimensional rotation formalisms for least-squares and Bayesian inverse kinematics

10.31219/osf.io/z3ftr ◽

2021 ◽

Author(s):

Ben Serrien ◽

Klevis Aliaj ◽

Todd Pataky

Keyword(s):

Least Squares ◽

Inverse Kinematics ◽

Degrees Of Freedom ◽

Estimation Error ◽

Computational Cost ◽

Three Dimensional ◽

Linear Least Squares ◽

Computationally Efficient ◽

Rotational Degrees Of Freedom ◽

Value Decomposition

Marker-based inverse kinematics (IK) is prone to errors arising from measurementnoise and soft-tissue artefacts. Various least-squares and Bayesian methods canbe applied to limit the estimation error to a minimum. Recently proposed meth-ods like Bayesian IK come at an increased computational cost however. In thistechnical paper, we present an overview of eight different least squares or BayesianIK methods, including their accuracy and computational load for IK problemsinvolving a single rigid body and three rotational degrees-of-freedom, whose at-titude is estimated from four noisy marker positions. The results indicate thatNon-Linear Least Squares, Variational Bayesian and full Bayesian IK are supe-rior to Singular Value Decomposition in terms of accuracy, with approximatelya two-fold error reduction. However, only Non-Linear Least Squares and Varia-tional Bayesian IK are computationally efficient enough to scale towards practicaluse in biomechanical applications, with computational durations of 1-10 ms; fullyBayesian procedures required approximately 30 s for single rotation calculations.All Python code and supplementary material can be found in this paper’s GitHubrepository: https://github.com/benserrien/pybik.

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A Femoral Clamp to Reduce Soft Tissue Artifact: Accuracy and Reliability in Measuring Three-Dimensional Knee Kinematics During Gait

Journal of Biomechanical Engineering ◽

10.1115/1.4045115 ◽

2019 ◽

Vol 142 (4) ◽

Author(s):

Ziyun Ding ◽

Manuela Güdel ◽

Samuel H. L. Smith ◽

Richard A. Ademefun ◽

Anthony M. J. Bull

Keyword(s):

Soft Tissue ◽

Knee Joint ◽

Degrees Of Freedom ◽

Intraclass Correlation ◽

Joint Kinematics ◽

Cluster Method ◽

Coefficient Of Determination ◽

Knee Joint Kinematics ◽

Soft Tissue Artifact ◽

Rigid Cluster

Abstract The accurate measurement of full six degrees-of-freedom (6DOFs) knee joint kinematics is prohibited by soft tissue artifact (STA), which remains the greatest source of error. The purpose of this study was to present and assess a new femoral clamp to reduce STA at the thigh. It was hypothesized that the device can preserve the natural knee joint kinematics pattern and outperform a conventional marker mounted rigid cluster during gait. Six healthy subjects were asked to walk barefoot on level ground with a cluster marker set (cluster gait) followed by a cluster-clamp-merged marker set (clamp gait) and their kinematics was measured using the cluster method in cluster gait and the cluster and clamp methods simultaneously in clamp gait. Two operators performed the gait measurement. A 6DOFs knee joint model was developed to enable comparison with the gold standard knee joint kinematics measured using a dual fluoroscopic imaging technique. One-dimensional (1D) paired t-tests were used to compare the knee joint kinematics waveforms between cluster gait and clamp gait. The accuracy was assessed in terms of the root-mean-square error (RMSE), coefficient of determination, and Bland–Altman plots. Interoperator reliability was assessed using the intraclass correlation coefficient (ICC). The result showed that the femoral clamp did not change the walking speed and knee joint kinematics waveforms. Additionally, clamp gait reduced the rotation and translation errors in the transverse plane and improved the interoperator reliability when compared to the rigid cluster method, suggesting a more accurate and reliable measurement of knee joint kinematics.

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