scholarly journals Compressive Loads on the Lumbar Spine During Lifting: 4D WATBAK versus Inverse Dynamics Calculations

2005 ◽  
Vol 2 (3-4) ◽  
pp. 149-159
Author(s):  
M. H. Cole ◽  
P. N. Grimshaw
Keyword(s):  
Lumbar Spine ◽  
Dynamic Model ◽  
Inverse Dynamics ◽  
Sagittal Plane ◽  
Three Dimensional ◽  
Work Capacity ◽  
Industrial Applications ◽  
Static Compression ◽  
Biomechanical Models ◽  
Occupational Setting

Numerous two- and three-dimensional biomechanical models exist for the purpose of assessing the stresses placed on the lumbar spine during the performance of a manual material handling task. More recently, researchers have utilised their knowledge to develop specific computer-based models that can be applied in an occupational setting; an example of which is 4D WATBAK. The model used by 4D WATBAK bases its predications on static calculations and it is assumed that these static loads reasonably depict the actual dynamic loads acting on the lumbar spine. Consequently, it was the purpose of this research to assess the agreement between the static predictions made by 4D WATBAK and those from a comparable dynamic model. Six individuals were asked to perform a series of five lifting tasks, which ranged from lifting 2.5 kg to 22.5 kg and were designed to replicate the lifting component of the Work Capacity Assessment Test used within Australia. A single perpendicularly placed video camera was used to film each performance in the sagittal plane. The resultant two-dimensional kinematic data were input into the 4D WATBAK software and a dynamic biomechanical model to quantify the compression forces acting at the L4/L5 intervertebral joint. Results of this study indicated that as the mass of the load increased from 2.5 kg to 22.5 kg, the static compression forces calculated by 4D WATBAK became increasingly less than those calculated using the dynamic model (mean difference ranged from 22.0% for 2.5 kg to 42.9% for 22.5 kg). This study suggested that, for research purposes, a validated three-dimensional dynamic model should be employed when a task becomes complex and when a more accurate indication of spinal compression or shear force is required. Additionally, although it is clear that 4D WATBAK is particularly suited to industrial applications, it is suggested that the limitations of such modelling tools be carefully considered when task-risk and employee safety are concerned.

Gait Analysis Using Multibody Simulation Tools and Inverse Dynamics Procedures

2005 ◽  
Author(s):  
Miguel Silva ◽  
Jorge Ambro´sio
Keyword(s):  
Gait Analysis ◽  
Inverse Dynamics ◽  
Three Dimensional ◽  
Biomechanical Model ◽  
Whole Body ◽  
Dynamics Analysis ◽  
Natural Coordinates ◽  
Kinematic Constraints ◽  
Biomechanical Models ◽  
Inverse Dynamics Analysis

The use of inverse dynamics methodologies for the evaluation of intersegmental reaction forces and the moments-of-force at the anatomical joints, in the framework of gait analysis, not only requires that appropriate biomechanical models are used but also that kinematic and kinetic data sets are available. This paper discusses the quality of the results of the inverse dynamics analysis with respect to the filtering procedures used and the kinematic consistency of the position, velocity and acceleration data. A three-dimensional whole body response biomechanical model based on a multibody formulation with natural coordinates is used. The model has 16 anatomical segments that are described using 33 rigid bodies in a total of 44 degrees-of-freedom. In biomechanical applications, one of the advantages of the current formulation is that the set of anatomical points used to reconstruct the spatial motion of the subject is also used to construct the set of natural coordinates that describe the biomechanical model itself. Based on the images collected by four synchronized video cameras, the three-dimensional trajectories of the anatomical points are reconstructed using standard photogrammetry techniques and Direct Linear Transformations. The trajectories obtained are then filtered in order to reduce the noise levels introduced during the reconstruction procedure using 2nd order Butterworth low-pass filters with properly chosen cut-off frequencies. The filtered data is used in the inverse dynamics analysis either directly or after being modified in order to ensure its consistency with the biomechanical model’s kinematic constraints. It is also shown that the use of velocities and accelerations consistent with the kinematic constraints or those obtained through the time derivatives of the spline interpolation curves of the reconstructed trajectories lead to similar results.

Capturing Three-Dimensional In Vivo Lumbar Intervertebral Joint Kinematics Using Dynamic Stereo-X-Ray Imaging

2013 ◽  
Vol 136 (1) ◽  
Author(s):  
Ameet K. Aiyangar ◽  
Liying Zheng ◽  
Scott Tashman ◽  
William J. Anderst ◽  
Xudong Zhang
Keyword(s):  
Lumbar Spine ◽  
Three Dimensional ◽  
Lumbar Vertebrae ◽  
Lumbar Vertebra ◽  
Weight Lifting ◽  
Data Set ◽  
X Ray ◽  
Biomechanical Models ◽  
Lifting Task

Availability of accurate three-dimensional (3D) kinematics of lumbar vertebrae is necessary to understand normal and pathological biomechanics of the lumbar spine. Due to the technical challenges of imaging the lumbar spine motion in vivo, it has been difficult to obtain comprehensive, 3D lumbar kinematics during dynamic functional tasks. The present study demonstrates a recently developed technique to acquire true 3D lumbar vertebral kinematics, in vivo, during a functional load-lifting task. The technique uses a high-speed dynamic stereo-radiography (DSX) system coupled with a volumetric model-based bone tracking procedure. Eight asymptomatic male participants performed weight-lifting tasks, while dynamic X-ray images of their lumbar spines were acquired at 30 fps. A custom-designed radiation attenuator reduced the radiation white-out effect and enhanced the image quality. High resolution CT scans of participants' lumbar spines were obtained to create 3D bone models, which were used to track the X-ray images via a volumetric bone tracking procedure. Continuous 3D intervertebral kinematics from the second lumbar vertebra (L2) to the sacrum (S1) were derived. Results revealed motions occurring simultaneously in all the segments. Differences in contributions to overall lumbar motion from individual segments, particularly L2–L3, L3–L4, and L4–L5, were not statistically significant. However, a reduced contribution from the L5–S1 segment was observed. Segmental extension was nominally linear in the middle range (20%–80%) of motion during the lifting task, but exhibited nonlinear behavior at the beginning and end of the motion. L5–S1 extension exhibited the greatest nonlinearity and variability across participants. Substantial AP translations occurred in all segments (5.0 ± 0.3 mm) and exhibited more scatter and deviation from a nominally linear path compared to segmental extension. Maximum out-of-plane rotations (<1.91 deg) and translations (<0.94 mm) were small compared to the dominant motion in the sagittal plane. The demonstrated success in capturing continuous 3D in vivo lumbar intervertebral kinematics during functional tasks affords the possibility to create a baseline data set for evaluating the lumbar spinal function. The technique can be used to address the gaps in knowledge of lumbar kinematics, to improve the accuracy of the kinematic input into biomechanical models, and to support development of new disk replacement designs more closely replicating the natural lumbar biomechanics.

Influence of dynamic factors on calculating cumulative low back loads

2005 ◽  
Vol 5 (2) ◽  
pp. 89-97
Author(s):  
Jack P. Callaghan ◽  
Kiera Keown ◽  
David M. Andrews
Keyword(s):  
Dynamic Model ◽  
Sagittal Plane ◽  
Average Error ◽  
Low Back ◽  
Materials Handling ◽  
Biomechanical Models ◽  
Modeling Approaches ◽  
Video Recordings ◽  
Dynamic Factors ◽  
Manual Materials Handling

This study examined the error induced in estimating cumulative low back loading for exposure to dynamic manual materials handling tasks by using either static or quasi-dynamic biomechanical models when compared to a dynamic model. Ten male subjects performed three sagittal plane lifting tasks at three different lifting speeds and using three different hand loads. Digitized video recordings and measured hand forces were collected in order to calculate cumulative L4/L5 spinal loading (compression, moment, joint shear, and reaction shear) using rigid link and single muscle equivalent biomechanical models. Cumulative loading was calculated using three modeling approaches: static, quasi-dynamic, and dynamic. The calculation of cumulative loading using the dynamic model was set as the "gold standard" and error in the static and quasi-dynamic approaches was determined by comparison with the dynamic model. The use of a quasi-dynamic model resulted in an average error of −2.76% across all 10 subjects, 3 tasks, 3 lifting speeds and 3 masses. The static model had an average error of −12.55%. The error in both modeling approaches was significantly effected by the type of task performed, mass lifted, speed of lift, and model variable examined indicating that neither model produced consistent errors across the lifting parameters. The small errors associated with the quasi-dynamic model indicates that it holds promise as a method to reduce the amount of data required to estimate cumulative loading yet still preserve the dynamic loading exposure of a manual materials handling task.

scholarly journals Three-Dimensional Motion Analysis of Lumbopelvic Rhythm During Trunk Extension

2016 ◽  
Vol 50 (1) ◽  
pp. 53-62 ◽  
Author(s):  
Michio Tojima ◽  
Naoshi Ogata ◽  
Yasuo Nakahara ◽  
Nobuhiko Haga
Keyword(s):  
Lumbar Spine ◽  
Linear Function ◽  
Motion Analysis ◽  
Sagittal Plane ◽  
Spinous Process ◽  
Three Dimensional ◽  
Quadratic Function ◽  
Muscle Groups ◽  
Lumbar Spinal ◽  
Trunk Extension

Abstract Hip–spine coordination, known as the lumbopelvic rhythm, can be expressed as the lumbar–hip ratio. The lumbopelvic rhythm and lumbar–hip ratio can be used to assess lower limb function. We clarified the lumbopelvic rhythm and lumbar–hip ratio during trunk extension. We established a novel set of marker positions for three-dimensional motion analysis to assess the lumbar spinal angle. The original markers were placed on both paravertebral muscle groups at the 11th thoracic spinous process level, the 10th and 12th thoracic spinous processes, and the pelvis. We measured angle data during trunk extension using three-dimensional motion analysis, and the data for eight healthy male subjects were categorized into backward and forward phases. The lumbar–hip ratio increased significantly from 1.2 to 1.9 (mean, 1.6) in the backward phase, indicating considerable movement of the lumbar spine compared with hip movement in the latter phase. In the forward phase, the ratio decreased significantly from 1.9 to 0.5 (mean, 1.5). After completion of 80% of the forward phase, the lumbar–hip ratio decreased to <1.0. The lumbopelvic rhythm for trunk extension was better expressed by a cubic or quadratic function than a linear function. According to a linear function, when the hip extends by 1°, lumbar spine extends by 1.9°. Therefore, lumbar spinal movement was greater than hip movement in the sagittal plane. The implication of the curved line would indicate lumbar extension instead of the limitation of hip extension.

Performance Analysis and Feedback Control of ATRIAS, A Three-Dimensional Bipedal Robot

2013 ◽  
Vol 136 (2) ◽  
Author(s):  
Alireza Ramezani ◽  
Jonathan W. Hurst ◽  
Kaveh Akbari Hamed ◽  
J. W. Grizzle
Keyword(s):  
Energy Efficiency ◽  
Dynamic Model ◽  
Degrees Of Freedom ◽  
Sagittal Plane ◽  
Center Of Mass ◽  
Three Dimensional ◽  
The Body ◽  
Energetic Efficiency ◽  
Natural Terrain ◽  
Walking Speeds

This paper develops feedback controllers for walking in 3D, on level ground, with energy efficiency as the performance objective. Assume The Robot Is A Sphere (ATRIAS) 2.1 is a new robot that has been designed for the study of 3D bipedal locomotion, with the aim of combining energy efficiency, speed, and robustness with respect to natural terrain variations in a single platform. The robot is highly underactuated, having 6 actuators and, in single support, 13 degrees of freedom. Its sagittal plane dynamics are designed to embody the spring loaded inverted pendulum (SLIP), which has been shown to provide a dynamic model of the body center of mass during steady running gaits of a wide diversity of terrestrial animals. A detailed dynamic model is used to optimize walking gaits with respect to the cost of mechanical transport (CMT), a dimensionless measure of energetic efficiency, for walking speeds ranging from 0.5 (m/s) to 1.4 (m/s). A feedback controller is designed that stabilizes the 3D walking gaits, despite the high degree of underactuation of the robot. The 3D results are illustrated in simulation. In experiments on a planarized (2D) version of the robot, the controller yielded stable walking.

On Squat Jump Exercise

2016 ◽  
Author(s):  
Dumitru I. Caruntu ◽  
Ricardo Moreno
Keyword(s):  
Dynamic Model ◽  
Inverse Dynamics ◽  
Sagittal Plane ◽  
Contact Point ◽  
Point Location ◽  
Squat Jump ◽  
Jump Exercise ◽  
Joint Contact ◽  
Good Agreement

This paper deals with the mechanics of the human leg and forces in the muscles, ligaments, and joint contact in the leg during a squat jump exercise. An inverse dynamics approach is used in this work. A 2-D dynamic model of one limb in the sagittal plane is used to investigate this ballistic task. Results are then compared to data available in the literature. They show good agreement. The response of the ligament forces and the tibio-femoral contact point location during the exercise are reported.

scholarly journals Fusing Accelerometry with Videography to Monitor the Effect of Fatigue on Punching Performance in Elite Boxers

Sensors ◽  
2020 ◽  
Vol 20 (20) ◽  
pp. 5749
Author(s):  
Nicos Haralabidis ◽  
David John Saxby ◽  
Claudio Pizzolato ◽  
Laurie Needham ◽  
Dario Cazzola ◽  
...  
Keyword(s):  
Inverse Dynamics ◽  
Sagittal Plane ◽  
Three Dimensional ◽  
Statistical Parametric Mapping ◽  
Shoulder Abduction ◽  
Inertial Measurement Units ◽  
Inertial Measurement ◽  
Fatigue Protocol ◽  
Custom Made ◽  
Measurement Units

Wearable sensors and motion capture technology are accepted instruments to measure spatiotemporal variables during punching performance and to study the externally observable effects of fatigue. This study aimed to develop a computational framework enabling three-dimensional inverse dynamics analysis through the tracking of punching kinematics obtained from inertial measurement units and uniplanar videography. The framework was applied to six elite male boxers performing a boxing-specific punch fatigue protocol. OpenPose was used to label left side upper-limb landmarks from which sagittal plane kinematics were computed. Custom-made inertial measurement units were embedded into the boxing gloves, and three-dimensional punch accelerations were analyzed using statistical parametric mapping to evaluate the effects of both fatigue and laterality. Tracking simulations of a sub-set of left-handed punches were formulated as optimal control problems and converted to nonlinear programming problems for solution with a trapezoid collocation method. The laterality analysis revealed the dominant side fatigued more than the non-dominant, while tracking simulations revealed shoulder abduction and elevation moments increased across the fatigue protocol. In future, such advanced simulation and analysis could be performed in ecologically valid contexts, whereby multiple inertial measurement units and video cameras might be used to model a more complete set of dynamics.

Pitching Effects of Buoyancy During Four Competitive Swimming Strokes

2014 ◽  
Vol 30 (5) ◽  
pp. 609-618 ◽  
Author(s):  
Raymond C.Z. Cohen ◽  
Paul W. Cleary ◽  
Simon M. Harrison ◽  
Bruce R. Mason ◽  
David L. Pease
Keyword(s):  
Sagittal Plane ◽  
Center Of Mass ◽  
National Level ◽  
Three Dimensional ◽  
Capture Process ◽  
Competitive Swimming ◽  
Biomechanical Models ◽  
Markerless Motion Capture ◽  
The Mean ◽  
Butterfly Stroke

The purpose of this study was to determine the pitching effects of buoyancy during all competitive swimming strokes—freestyle, backstroke, butterfly, and breaststroke. Laser body scans of national-level athletes and synchronized multiangle swimming footage were used in a novel markerless motion capture process to produce three-dimensional biomechanical models of the swimming athletes. The deforming surface meshes were then used to calculate swimmer center-of-mass (CoM) positions, center-of-buoyancy (CoB) positions, pitch buoyancy torques, and sagittal plane moments of inertia (MoI) throughout each stroke cycle. In all cases the mean buoyancy torque tended to raise the legs and lower the head; however, during part of the butterfly stroke the instantaneous buoyancy torque had the opposite effect. The swimming strokes that use opposing arm and leg strokes (freestyle and backstroke) had smaller variations in CoM positions, CoB positions, and buoyancy torques. Strokes with synchronized left-right arm and leg movement (butterfly and breaststroke) had larger variations in buoyancy torques, which impacts the swimmer’s ability to maintain a horizontal body pitch for these strokes. The methodology outlined in this paper enables the rotational effects of buoyancy to be better understood by swimmers, allowing better control of streamlined horizontal body positioning during swimming to improve performance.

scholarly journals A computer-based approach for developing linamarase inhibitory agents

2020 ◽  
Vol 5 (7) ◽  
Author(s):  
Lucas Paul ◽  
Celestin N. Mudogo ◽  
Kelvin M. Mtei ◽  
Revocatus L. Machunda ◽  
Fidele Ntie-Kang
Keyword(s):  
Structure Elucidation ◽  
Three Dimensional ◽  
Data Bank ◽  
Competitive Inhibitor ◽  
Industrial Applications ◽  
Dimensional Structure ◽  
Full Understanding ◽  
The Poor ◽  
Computer Based ◽  
Inhibitory Agents

AbstractCassava is a strategic crop, especially for developing countries. However, the presence of cyanogenic compounds in cassava products limits the proper nutrients utilization. Due to the poor availability of structure discovery and elucidation in the Protein Data Bank is limiting the full understanding of the enzyme, how to inhibit it and applications in different fields. There is a need to solve the three-dimensional structure (3-D) of linamarase from cassava. The structural elucidation will allow the development of a competitive inhibitor and various industrial applications of the enzyme. The goal of this review is to summarize and present the available 3-D modeling structure of linamarase enzyme using different computational strategies. This approach could help in determining the structure of linamarase and later guide the structure elucidation in silico and experimentally.

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