Development and Assessment of a Microcomputed Tomography Compatible Five Degrees-of-Freedom Knee Joint Motion Simulator

Currently available knee joint kinematic tracking systems fail to nondestructively capture the subtle variation in joint and soft tissue kinematics that occur in native, injured, and reconstructed joint states. Microcomputed tomography (CT) imaging has the potential as a noninvasive, high-resolution kinematic tracking system, but no dynamic simulators exist to take advantage of this. The purpose of this work was to develop and assess a novel micro-CT compatible knee joint simulator to quantify the knee joint's kinematic and kinetic response to clinically (e.g., pivot shift test) and functionally (e.g., gait) relevant loading. The simulator applies closed-loop, load control over four degrees-of-freedom (DOF) (internal/external rotation, varus/valgus rotation, anterior/posterior translation, and compression/distraction), and static control over a fifth degree-of-freedom (flexion/extension). Simulator accuracy (e.g., load error) and repeatability (e.g., coefficient of variation) were assessed with a cylindrical rubber tubing structure and a human cadaveric knee joint by applying clinically and functionally relevant loads along all active axes. Micro-CT images acquired of the joint at a loaded state were then used to calculate joint kinematics. The simulator loaded both the rubber tubing and the cadaveric specimen to within 0.1% of the load target, with an intertrial coefficient of variation below 0.1% for all clinically relevant loading protocols. The resultant kinematics calculated from the acquired images agreed with previously published values, and produced errors of 1.66 mm, 0.90 mm, 4.41 deg, and 1.60 deg with respect to anterior translation, compression, internal rotation, and valgus rotation, respectively. All images were free of artifacts and showed knee joint displacements in response to clinically and functionally loading with isotropic CT image voxel spacing of 0.15 mm. The results of this study demonstrate that the joint-motion simulator is capable of applying accurate, clinically and functionally relevant loads to cadaveric knee joints, concurrent with micro-CT imaging. Nondestructive tracking of bony landmarks allows for the precise calculation of joint kinematics with less error than traditional optical tracking systems.

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Control System for an Elbow Joint Motion Simulator

Volume 9: Mechanical Systems and Control, Parts A, B, and C ◽

10.1115/imece2007-42806 ◽

2007 ◽

Author(s):

Patrick J. Schimoler ◽

Jeffrey S. Vipperman ◽

Laurel Kuxhaus ◽

Angela M. Flamm ◽

Daniel D. Budny ◽

...

Keyword(s):

Control System ◽

Elbow Joint ◽

Degrees Of Freedom ◽

Biceps Brachii ◽

Control Algorithms ◽

Joint Motion ◽

Motion Simulator ◽

Co Activation ◽

Flexion Extension ◽

The Many

The many muscles crossing the elbow joint allow for its motions to be created from different combinations of muscular activations. Muscles are strictly contractile elements and the joints they surround rely on varying loads from opposing antagonists for stability and movement. In designing a control system to actuate an elbow in a realistic manner, unidirectional, tendon-like actuation and muscle co-activation must be considered in order to successfully control the elbow’s two degrees of freedom. Also important is the multifunctionality of certain muscles, such as the biceps brachii, which create moments impacting both degrees of freedom: flexion / extension and pronation / supination. This paper seeks to develop and implement control algorithms on an elbow joint motion simulator that actuates cadaveric elbow specimens via four major muscles that cross the elbow joint. The algorithms were validated using an anatomically-realistic mechanical elbow. Clinically-meaningful results, such as the evaluation of radial head implants, can only be obtained under repeatable, realistic conditions; therefore, physiologic motions must be created by the application of appropriate loads. This is achieved by including load control on the muscles’ actuators as well as displacement control on both flexion / extension and supination / pronation.

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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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Online sonification improves cycling performance through kinematic and muscular reorganisations

Scientific Reports ◽

10.1038/s41598-020-76498-0 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Benjamin O’Brien ◽

Romain Hardouin ◽

Guillaume Rao ◽

Denis Bertin ◽

Christophe Bourdin

Keyword(s):

Knee Joint ◽

Real Time ◽

Degrees Of Freedom ◽

Ventilatory Threshold ◽

Cycling Performance ◽

Joint Kinematics ◽

Auditory Display ◽

Beneficial Effects ◽

Silent Condition

AbstractBased on a previous study that demonstrated the beneficial effects of sonification on cycling performance, this study investigated which kinematic and muscular activities were changed to pedal effectively. An online error-based sonification strategy was developed, such that, when negative torque was applied to the pedal, a squeak sound was produced in real-time in the corresponding headphone. Participants completed four 6-min cycling trials with resistance values associated with their first ventilatory threshold. Different auditory display conditions were used for each trial (Silent, Right, Left, Stereo), where sonification was only presented for 20 s at the start of minutes 1, 2, 3, and 4. Joint kinematics and right leg muscular activities of 10 muscles were simultaneously recorded. Our results showed participants were more effective at pedalling when presented sonification, which was consistent with previously reported findings. In comparison to the Silent condition, sonification significantly limited ankle and knee joint ranges of motion and reduced muscular activations. These findings suggest performance-based sonification significantly affected participants to reduce the complexity of the task by altering the coordination of the degrees of freedom. By making these significant changes to their patterns, participants improved their cycling performance despite lowering joint ranges of motion and muscular activations.

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Knee joint motion: Description and measurement

Proceedings of the Institution of Mechanical Engineers Part H Journal of Engineering in Medicine ◽

10.1243/0954411981534132 ◽

1998 ◽

Vol 212 (5) ◽

pp. 357-372 ◽

Cited By ~ 54

Author(s):

A M J Bull ◽

A A Amis

Keyword(s):

Knee Joint ◽

Degrees Of Freedom ◽

Euler Angle ◽

Helical Axis ◽

Joint Motion ◽

Spatial Motion ◽

Electromagnetic Devices ◽

Linkage Methods ◽

Knee Joint Motion ◽

6 Degrees Of Freedom

Knee joint motion has been described in various ways in the literature. These are explained and commented on. Two methods for describing knee joint motion with 6 degrees of freedom (DOF)—Euler angle and the helical axis of motion—are discussed. Techniques to measure joint motion which can either approximate the motion to less than 6 DOF or fully measure the spatial motion are identified. These include electrical linkage methods, radiographic and video techniques, fluoroscopic techniques and electromagnetic devices. In those cases where the full spatial motion is measured, the data are available to describe the motion in simpler terms (or with less DOF) than three rotations with three translations. This is necessary for clinical application and to facilitate communication between the clinician and the engineer.

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Development of a knee joint motion simulator to evaluate deep knee flexion of artificial knee joints

2008 30th Annual International Conference of the IEEE Engineering in Medicine and Biology Society ◽

10.1109/iembs.2008.4650230 ◽

2008 ◽

Author(s):

Y. Takano ◽

M. Ueno ◽

K. Kiguchi ◽

J. Itou ◽

M. Mawatari ◽

...

Keyword(s):

Knee Joint ◽

Knee Flexion ◽

Knee Joints ◽

Joint Motion ◽

Motion Simulator ◽

Knee Joint Motion

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Differences in tibiofemoral kinematics between the unloaded robotic passive path and a weightbearing knee simulator

Orthopedic Reviews ◽

10.4081/or.2012.e2 ◽

2012 ◽

Vol 3 (2) ◽

pp. 2 ◽

Cited By ~ 4

Author(s):

Markus Wünschel ◽

Ulf Leichtle ◽

JiaHsuan Lo ◽

Nikolaus Wülker ◽

Otto Müller

Keyword(s):

Knee Joint ◽

Degrees Of Freedom ◽

Weight Bearing ◽

Reaction Force ◽

Joint Kinematics ◽

Vertical Ground Reaction Force ◽

Knee Simulator ◽

6 Degrees Of Freedom ◽

Tibiofemoral Kinematics

Cadaveric in vitro studies are essential to test hypotheses concerning surgical manipulations in the same individual. Robotic technologies as well as different knee-models have been developed to get an in-depth comprehension of knee joint kinematics. The purpose of this study was to compare utilization of these different established principles. Ten human cadaveric knee specimens were used to measure the kinematics during a weight-bearing flexion in a 6-degrees-of-freedom knee simulator. While flexing the knee, joint quadriceps muscle forces were dynamically simulated to reach a vertical ground reaction force of 100N. Fourteen knee specimens were mounted in 6-degrees-of-freedom robotic manipulator with a universal force sensor. The unloaded flexing motion of each specimen was measured by finding positions for each degree of flexion where all forces are minimal (passive path). The kinematic data of the kneesimulator and the robot concerning internal-external rotation, anterior-posterior translation, varus-valgus motion, and medial-lateral translation was examined. For all investigated degrees of freedom the kinematics of the robotic passive path differed from the loaded kinematics in the knee simulator. Simulated bodyweight as well as the examination method used has a substantial influence on joint kinematics during flexion which has to be considered when interpreting biomechanical studies as well as clinical tests.

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