Application of the Joint Coordinate System to Three-Dimensional Joint Attitude and Movement Representation: A Standardization Proposal

1993 ◽  
Vol 115 (4A) ◽  
pp. 344-349 ◽  
Author(s):  
G. K. Cole ◽  
B. M. Nigg ◽  
J. L. Ronsky ◽  
M. R. Yeadon
Keyword(s):  
Coordinate System ◽  
Three Dimensional ◽  
Axial Rotation ◽  
Distal Segment ◽  
The Body ◽  
Proximal Segment ◽  
Practical Applications ◽  
Flexion Extension ◽  
Joint Coordinate System ◽  
Selection Of

The selection of an appropriate and/or standardized method for representing 3-D joint attitude and motion is a topic of popular debate in the field of biomechanics. The joint coordinate system (JCS) is one method that has seen considerable use in the literature. The JCS consists of an axis fixed in the proximal segment, an axis fixed in the distal segment, and a “floating” axis. There has not been general agreement in the literature on how to select the body fixed axes of the JCS. The purpose of this paper is to propose a single definition of the body fixed axes of the JCS. The two most commonly used sets of body fixed axes are compared and the differences between them quantified. These differences are shown to be relevant in terms of practical applications of the JCS. Argumentation is provided to support a proposal for a standardized selection of body fixed axes of the JCS consisting of the axis eˆ1 embedded in the proximal segment and chosen to represent flexion-extension, the “floating” axis eˆ2 chosen to represent ad-abduction, and the axis eˆ3 embedded in the distal segment and chosen to represent axial rotation of that segment. The algorithms for the JCS are then documented using generalized terminology.

scholarly journals Robust Identification of Three-Dimensional Thumb and Index Finger Kinematics With a Minimal Set of Markers

2013 ◽  
Vol 135 (9) ◽  
Author(s):  
Raviraj Nataraj ◽  
Zong-Ming Li
Keyword(s):  
Coordinate System ◽  
Degrees Of Freedom ◽  
Index Finger ◽  
Three Dimensional ◽  
Axial Rotation ◽  
Solution Model ◽  
Convergence Criteria ◽  
Minimal Set ◽  
Motion Error ◽  
Flexion Extension

This study presents a methodology to determine thumb and index finger kinematics while utilizing a minimal set of markers. The motion capture of skin-surface markers presents inherent challenges for the accurate and comprehensive measurement of digit kinematics. As such, it is desirable to utilize robust methods for assessing digit kinematics with fewer markers. The approach presented in this study involved coordinate system alignment, locating joint centers of rotation, and a solution model to estimate three-dimensional (3-D) digit kinematics. The solution model for each digit was based on assumptions of rigid-body interactions, specific degrees of freedom (DOFs) at each located joint, and the aligned coordinate system definitions. Techniques of inverse kinematics and optimization were applied to calculate the 3-D position and orientation of digit segments during pinching between the thumb and index finger. The 3-D joint center locations were reliably fitted with mean coefficients of variation below 5%. A parameterized form of the solution model yielded feasible solutions that met specified tolerance and convergence criteria for over 85% of the test points. The solution results were intuitive to the pinching function. The thumb was measured to be rotated about the CMC joint to bring it into opposition to the index finger and larger rotational excursions (>10 deg) were observed in flexion/extension compared to abduction/adduction and axial rotation for all joints. While the solution model produced results similar to those computed from a full marker set, the model facilitated the usage of fewer markers, which inherently lessened the effects of passive motion error and reduced the post-experimental effort required for marker processing.

Kinematics and Laxity of Ulnohumeral Joint Under Valgus-Varus Stress

1998 ◽  
Vol 02 (01) ◽  
pp. 45-54 ◽  
Author(s):  
Shinji Tanaka ◽  
Kai-Nan An ◽  
Bernard F. Morrey
Keyword(s):  
Elbow Joint ◽  
Three Dimensional ◽  
Elbow Flexion ◽  
Axial Rotation ◽  
Joint Laxity ◽  
Treatment Modalities ◽  
Trochlear Groove ◽  
Flexion Extension ◽  
Varus Stress ◽  
Baseline Information

Three-dimensional kinematics of the ulnohumeral joint under simulated active elbow joint flexion-extension was obtained by using an electromagnetic tacking device. The joint motion was analyzed based on Eulerian angle description. In order to minimize the effect of "downstream cross-talk" on calculation of the three Eulerian angles, an optimal axis to best represent flexion-extension of the elbow joint was established. This axis, on average, is close to the line joining the centers of the capitellum and the trochlear groove. Furthermore, joint laxity under valgus-varus stress was also examined. With the weight of the forearm as the stress, maximums of 7.6° valgus-varus laxity and 5.3° axial rotation laxity were observed within a range of elbow flexion. The results of this study provide useful baseline information on joint laxity for the evaluation of elbow joints with implant replacements and other surgical treatment modalities.

scholarly journals Biomechanical Analysis of Allograft Spacer Failure as a Function of Cortical-Cancellous Ratio in Anterior Cervical Discectomy/Fusion: Allograft Spacer Alone Model

2020 ◽  
Vol 10 (18) ◽  
pp. 6413
Author(s):  
Ji-Won Kwon ◽  
Hwan-Mo Lee ◽  
Tae-Hyun Park ◽  
Sung Jae Lee ◽  
Young-Woo Kwon ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Element Model ◽  
Axial Rotation ◽  
Biomechanical Analysis ◽  
Flexion Extension ◽  
Hybrid Motion ◽  
Anterior Cervical Discectomy Fusion ◽  
Flexion And Extension ◽  
Additional Fixation ◽  
Lateral Walls

The design and ratio of the cortico-cancellous composition of allograft spacers are associated with graft-related problems, including subsidence and allograft spacer failure. Methods: The study analyzed stress distribution and risk of subsidence according to three types (cortical only, cortical cancellous, cortical lateral walls with a cancellous center bone) and three lengths (11, 12, 14 mm) of allograft spacers under the condition of hybrid motion control, including flexion, extension, axial rotation, and lateral bending,. A detailed finite element model of a previously validated, three-dimensional, intact C3–7 segment, with C5–6 segmental fusion using allograft spacers without fixation, was used in the present study. Findings: Among the three types of cervical allograft spacers evaluated, cortical lateral walls with a cancellous center bone exhibited the highest stress on the cortical bone of spacers, as well as the endplate around the posterior margin of the spacers. The likelihood of allograft spacer failure was highest for 14 mm spacers composed of cortical lateral walls with a cancellous center bone upon flexion (PVMS, 270.0 MPa; 250.2%) and extension (PVMS: 371.40 MPa, 344.2%). The likelihood of allograft spacer subsidence was also highest for the same spacers upon flexion (PVMS, 4.58 MPa; 28.1%) and extension (PVMS: 12.71 MPa, 78.0%). Conclusion: Cervical spacers with a smaller cortical component and of longer length can be risk factors for allograft spacer failure and subsidence, especially in flexion and extension. However, further study of additional fixation methods, such as anterior plates/screws and posterior screws, in an actual clinical setting is necessary.

scholarly journals The 6-Plus–Person Lift Transfer Technique Compared With Other Methods of Spine Boarding

2008 ◽  
Vol 43 (1) ◽  
pp. 6-13 ◽  
Author(s):  
Gianluca Del Rossi ◽  
Mary Beth H. Horodyski ◽  
Bryan P. Conrad ◽  
Christian P. Di Paola ◽  
Matthew J. Di Paola ◽  
...  
Keyword(s):  
Spinal Injury ◽  
Three Dimensional ◽  
Axial Rotation ◽  
Linear Displacement ◽  
Angular Motion ◽  
Spinal Segment ◽  
Spinal Motion ◽  
Spinal Immobilization ◽  
Flexion Extension ◽  
Spine Board

Abstract Context: To achieve full spinal immobilization during on-the-field management of an actual or potential spinal injury, rescuers transfer and secure patients to a long spine board. Several techniques can be used to facilitate this patient transfer. Objective: To compare spinal segment motion of cadavers during the execution of the 6-plus–person (6+) lift, lift-and-slide (LS), and logroll (LR) spine-board transfer techniques. Design: Crossover study. Setting: Laboratory. Patients or Other Participants: Eight medical professionals (1 woman, 7 men) with 5 to 32 years of experience were enlisted to help carry out the transfer techniques. In addition, test conditions were performed on 5 fresh cadavers (3 males, 2 females) with a mean age of 86.2 ± 11.4 years. Main Outcomes Measure(s): Three-dimensional angular and linear motions initially were recorded during execution of transfer techniques, initially using cadavers with intact spines and then after C5-C6 spinal segment destabilization. The mean maximal linear displacement and angular motion obtained and calculated from the 3 trials for each test condition were included in the statistical analysis. Results: Flexion-extension angular motion, as well as anteroposterior and distraction-compression linear motion, did not vary between the LR and either the 6+ lift or LS. Compared with the execution of the 6+ lift and LS, the execution of the LR generated significantly more axial rotation (P  =  .008 and .001, respectively), more lateral flexion (P  =  .005 and .003, respectively), and more medial-lateral translation (P  =  .003 and .004, respectively). Conclusions: A small amount of spinal motion is inevitable when executing spine-board transfer techniques; however, the execution of the 6+ lift or LS appears to minimize the extent of motion generated across a globally unstable spinal segment.

FINITE ELEMENT MODELING OF HUMAN THORACIC SPINE

2004 ◽  
Vol 08 (04) ◽  
pp. 133-144 ◽  
Author(s):  
Tian-Xia Qiu ◽  
Ee-Chon Teo
Keyword(s):  
Finite Element ◽  
Thoracic Spine ◽  
Three Dimensional ◽  
Axial Rotation ◽  
Torsional Stiffness ◽  
Fe Model ◽  
Thoracic Vertebrae ◽  
Fundamental Information ◽  
Flexion Extension ◽  
Scoliosis Correction

Mathematical models, which can accurately represent the geometric, material and physical characteristics of the human spine structure, are useful in predicting biomechanical behaviors of the spine. In this study, a three-dimensional finite element (FE) model of thoracic spine (T1–T12) was developed, based on geometrical data of embalmed thoracic vertebrae (T1–T12) obtained from a precise flexible digitizer, and validated against published thoracolumbar experimental results in terms of the torsional stiffness of the whole thoracic spine (T1–T12) under axial torque alone and combined with distraction and compression loads. The torsional stiffness was increased by over 60% with application of a 425 N distraction force. A trend in increasing torsional stiffness with increasing distraction forces was detected. The validated model was then loaded under moment rotation in three anatomical planes to determine the ranges of motion (ROMs). The ROMs were approximately 37°, 31°, 32°, 51° for flexion, extension, lateral bending and axial rotation, respectively. These results may offer an insight to better understanding the kinematics of the human thoracic spine and provide clinically relevant fundamental information for the evaluation of spinal stability and instrumented devices functionality for optimal scoliosis correction.

A biomechanical comparison of three anterior thoracolumbar implants after corpectomy: are two screws better than one?

2006 ◽  
Vol 4 (3) ◽  
pp. 213-218 ◽  
Author(s):  
Dean Chou ◽  
Adolfo Espinoza Larios ◽  
Robert H. Chamberlain ◽  
Mary S. Fifield ◽  
Roger Hartl ◽  
...  
Keyword(s):  
Biomechanical Testing ◽  
Three Dimensional ◽  
Axial Rotation ◽  
Single Screw ◽  
Flexion Extension ◽  
Rod System ◽  
Mesh Cage ◽  
Left And Right ◽  
Plate System ◽  
Better Than

Object A flexibility experiment using human cadaveric thoracic spine specimens was performed to determine biomechanical differences among thoracolumbar two-screw plate, single-screw plate, and dual-rod systems. A secondary goal was to investigate differences in the ability of the systems to stabilize the spine after a one- or two-level corpectomy. Methods The authors evaluated 21 cadaveric spines implanted with a titanium mesh cage and three types of anterior thoracolumbar supplementary instrumentation after one-level thoracic corpectomies. Pure moments were applied quasistatically while three-dimensional motion was measured optoelectronically. The lax zone, stiff zone, and range of motion (ROM) were measured during flexion, extension, left and right lateral bending, and left and right axial rotation. Corpectomies were expanded to two levels, and testing was repeated with longer hardware. Biomechanical testing showed that the single-bolt plate system was no different from the dual-rod system with two screws in limiting ROM. The single-bolt plate system performed slightly better than the two-screw plate system. Across the same two levels, there was an average of 19% more motion after a two-level corpectomy than after a one-level corpectomy. In general, however, the difference across the different loading modes was insignificant. Conclusions Biomechanically, the single-screw plate system is equivalent to a two-screw dual-rod and a two-screw plate system. All three systems performed similarly in stabilizing the spine after one- or two-level corpectomies.

scholarly journals EFFECTS OF THE SCHROTH METHOD IN CHILDREN WITH IDIOPATHIC SCOLIOSIS

2019 ◽  
Vol 16 (2) ◽  
pp. 749
Author(s):  
Bojan Jorgić ◽  
Petra Mančić ◽  
Saša Milenković ◽  
Nikola Jevtić ◽  
Mladen Živković
Keyword(s):  
Idiopathic Scoliosis ◽  
Sagittal Plane ◽  
Three Dimensional ◽  
Exercise Program ◽  
Frontal Plane ◽  
Axial Rotation ◽  
The Body ◽  
Scoliosis Correction ◽  
Lateral Curvature ◽  
Positive Effect

Scoliosis is a multifactorial three-dimensional (3D) spinal deformation which always includes elementary deformations on three planes: a lateral curvature on the frontal plane, loss of natural physiological curvature on the sagittal plane and, in most cases, increase of lordosis in the lumbosacral joint (hyperlordosis), and a (very typical) vertebral axial rotation on the horizontal plane. One of the best methods in scoliosis correction is the Schroth method. In view of the above, the objective of this study is to identify the effects of the Schroth method on correcting functional-motor status in children with adolescent idiopathic scoliosis (IS). The participant sample comprised 20 children, of an average age of 14.5, who took part in the 10-day Schroth Camp. The following measure instruments were used for the assessment of the effect of the Schroth method: the Sorensen test, the Sit-and-reach test, and height assessment. Statistically significant improvements were identified across the results of all three tests, for the Sorensen test: 45.6±19.29 s, the Sit-and-reach test: 4.05±2.25 cm, and height 1.4±0.66 cm. It can be concluded that the conducted Schroth method exercise program exerted a positive effect on improving motor functionality, as well as enhancing flexibility and isometric endurance of the lumbar extensors of the spine. Additionally, there was an increase in height, which indicates a positive effect in terms of the functionality and symmetry of the left and right sides of the body, and in terms of improved posture on the frontal and sagittal planes.

scholarly journals Finite element analysis of wedge and biconcave deformity in four different height restoration after augmentation of osteoporotic vertebral compression fracture

2020 ◽  
Author(s):  
Xiao-Hua Zuo ◽  
Ying-Bing Chen ◽  
Peng Xie ◽  
Wen-Dong Zhang ◽  
Xiang-Yun Xue ◽  
...  
Keyword(s):  
Finite Element ◽  
Three Dimensional ◽  
Axial Rotation ◽  
Neutral Position ◽  
Element Analysis ◽  
Flexion Extension ◽  
Dimensional Finite Element ◽  
Von Mises ◽  
Three Dimensional Finite Element ◽  
Wedge Fracture

Abstract Purpose Biomechanical comparison of wedge and biconcave deformity of different height restoration after augmentation of osteoporotic vertebral compression fractures was analyzed by three-dimensional finite element analysis (FEA). Methods Three-dimensional finite element model (FEM) of T11-L2 segment was constructed from CT scan of elderly osteoporosis patient. The von Mises stresses of vertebrae, intervertebral disc, facet joints, displacement, and range of motion (ROM) of wedge and biconcave deformity were compared at four different heights (Genant 0–3 grade) after T12 vertebral augmentation. Results In wedge deformity, the stress of T12 decreased as the vertebral height in neutral position, flexion, extension and left axial rotation, whereas increased sharply in bending at Genant 0; L1 and L2 decreased in all positions excluding flexion of L2, and T11 increased in neutral position, flexion, extension, and right axial rotation at Genant 0. No significant changes in biconcave deformity. The stress of T11-T12, T12-L1, and L1-L2 intervertebral disc gradually increased or decreased under other positions in wedge fracture, whereas L1-L2 no significant change in biconcave fracture. The utmost overall facet joint stress is at Genant 3, whereas there is no significant change under the same position in biconcave fracture. The displacement and ROM of the wedge fracture had ups and downs, while a decline in all positions excluding extension in biconcave fracture. Conclusions The vertebral restoration height after augmentation to Genant 0 affects the von Mises stress, displacement, and ROM in wedge deformity, which may increase the risk of fracture; Whereas restored or not in biconcave deformity.

scholarly journals The natural selection of metabolism and mass selects allometric transitions from prokaryotes to mammals

2016 ◽  
Author(s):  
Lars Witting
Keyword(s):  
Natural Selection ◽  
Body Mass ◽  
Three Dimensional ◽  
The Body ◽  
Net Energy ◽  
A Value ◽  
Spatial Dimensions ◽  
Self Replication ◽  
Selection Of ◽  
Evolution Proceeds

AbstractInter-specific body mass allometries can evolve from the natural selection of mass, with ±1/4 and ±3/4 exponents following from the geometry of intra-specific interactions when density dependent foraging occurs in two spatial dimensions (2D, Witting, 1995). The corresponding values for three dimensional interactions (3D) are ±1/6 and ±5/6.But the allometric exponents in mobile organisms are more diverse than the prediction. The exponent for mass specific metabolism tends to cluster around −1/4 and −1/6 in terrestrial and pelagic vertebrates, but it is strongly positive in prokaryotes with an apparent value around 5/6 (DeLong et al., 2010). And a value around zero has been reported in protozoa, and on the macro evolutionary scale from prokaryotes over larger unicells to multicellular vertebrates (Makarieva et al., 2005, 2008).I show that mass specific metabolism can be selected as the pace of the resource handling that generates net energy for self-replication and the selection of mass, and that this selection of metabolism and mass is sufficient to explain metabolic exponents that decline from 5/6 over zero to −1/6 in 3D, and from 3/4 over zero to −1/4 in 2D. The decline follows from a decline in the importance of mass specific metabolism for the selection of mass, and it suggestsi) that the body mass variation in prokaryotes is selected from primary variation in mass specific metabolism,ii) that the variation in multicellular animals are selected from primary variation in the handling and/or densities of the underlying resources,iii) that protozoa are selected as an intermediate lifeform between prokaryotes and multicellular animals, andiv) that macro evolution proceeds along an upper bound on mass specific metabolism.

Flight performance and visual control of flight of the free-flying housefly ( Musca domestica L.) I. Organization of the flight motor

1986 ◽  
Vol 312 (1158) ◽  
pp. 527-551 ◽  
Keyword(s):  
Coordinate System ◽  
Degrees Of Freedom ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Rigid Bodies ◽  
The Body ◽  
Midsagittal Plane ◽  
Torque Vector ◽  
Translation Velocity ◽  
Flight Motor

Free-flying houseflies have been filmed simultaneously from two sides. The orientation of the flies’ body axes in three-dimensional space can be seen on the films. A method is presented for the reconstruction of the flies’ movements in a fly-centred coordinate system, relative to an external coordinate system and relative to the airstream. The flies are regarded as three-dimensionally rigid bodies. They move with respect to the six degrees of freedom they thus possess. The analysis of the organization of the flight motor from the kinematic data leads to the following conclusions: the sideways movements can, at least qualitatively, be explained by taking into account the sideways forces resulting from rolling the body about the long axis and the influence of inertia. Thus, the force vector generated by the flight motor is most probably located in the fly’s midsagittal plane. The direction of this vector can be varied by the fly in a restricted range only. In contrast, the direction of the torque vector can be freely adjusted by the fly. No coupling between the motor force and the torques is indicated. Changes of flight direction may be explained by changes in the orientation of the body axes: straight flight at an angle of sideslip differing from zero is due to rolling. Sideways motion during the banked turns as well as the decrease of translation velocity observed in curves are a consequence of the inertial forces and rolling. The results are discussed with reference to studies about the aerodynamic performance of insects and the constraints for aerial pursuit.

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