FLUOROSCOPIC ANALYSIS FOR THE ESTIMATION OF IN VIVO ELBOW KINEMATICS: INFLUENCE OF 3D MODEL

2012 ◽  
Vol 12 (03) ◽  
pp. 1250046 ◽  
Author(s):  
LUCA TERSI ◽  
SILVIA FANTOZZI ◽  
RITA STAGNI ◽  
ANGELO CAPPELLO
Keyword(s):  
Cost Function ◽  
Three Dimensional ◽  
Elbow Flexion ◽  
Estimation Algorithm ◽  
Healthy Male Subject ◽  
Distance Map ◽  
3D Fluoroscopy ◽  
Flexion Extension ◽  
Single Bone

The reliable knowledge that model-based three-dimensional (3D) fluoroscopy can provide about in vivo joints kinematics is essential to diagnose orthopedic pathologies, develop new prosthesis, and evaluate clinical procedures. To exploit 3D fluoroscopy for the analysis of elbow kinematics, its use was evaluated considering a single model for the forearm or two different models for the ulna and radius. Active elbow flexion-extension and prono-supination motor tasks of a healthy male subject were acquired by means of fluoroscopy. The 3D bone models were automatically aligned to the relevant projections. The pose estimation algorithm sought the tangency condition of the projection rays with the model surface, minimizing a cost function and exploiting an adaptive distance map. Five iterative guided alignments were performed to avoid the final convergence to a local minimum. The results highlighted the critical alignment of the ulna/radius model, particularly when prono-supination is performed. From the physiological motion patterns and given the values of the cost function, 3D fluoroscopy was proven to be applicable to the analysis of the elbow kinematics when single bone models for the ulna and radius are used.

In Vivo Determination of the Direction of Rotation and Moment-Angle Relationship of Individual Elbow Muscles

1998 ◽  
Vol 120 (5) ◽  
pp. 625-633 ◽  
Author(s):  
L. Zhang ◽  
J. Butler ◽  
T. Nishida ◽  
G. Nuber ◽  
H. Huang ◽  
...  
Keyword(s):  
Muscle Activation ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Elbow Flexion ◽  
Joint Movement ◽  
Flexion Extension ◽  
Relationship Of ◽  
Three Dimensional Space

The direction of rotation (DOR) of individual elbow muscles, defined as the direction in which a muscle rotates the forearm relative to the upper arm in three-dimensional space, was studied in vivo as a function of elbow flexion and forearm rotation. Electrical stimulation was used to activate an individual muscle selectively, and the resultant flexion-extension, supination-pronation, and varus-valgus moments were used to determine the DOR. Furthermore, multi-axis moment-angle relationships of individual muscles were determined by stimulating the muscle at a constant submaximal level across different joint positions, which was assumed to result in a constant level of muscle activation. The muscles generate significant moments about axes other than flexion-extension, which is potentially important for actively controlling joint movement and maintaining stability about all axes. Both the muscle DOR and the multi axis moments vary with the joint position systematically. Variations of the DOR and moment-angle relationship across muscle twitches of different amplitudes in a subject were small, while there were considerable variations between subjects.

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.

Investigation of Vibration Characteristics of the Ligamentous Lumbar Spine Using the Finite Element Approach

1994 ◽  
Vol 116 (4) ◽  
pp. 377-383 ◽  
Author(s):  
Vijay K. Goel ◽  
Hosang Park ◽  
Weizeng Kong
Keyword(s):  
Finite Element ◽  
Resonant Frequency ◽  
Cyclic Load ◽  
Static Load ◽  
Three Dimensional ◽  
Element Model ◽  
Upper Body ◽  
Experimental Investigations ◽  
Flexion Extension

A nonlinear, three-dimensional finite element model of the ligamentous L4-SI segment was developed to analyze the dynamic response of the spine in the absence of damping. The effects of the upper body mass were simulated by including a mass of 40 kg on the L4 vertebral body. The modal analyses of the model indicated a resonant frequency of 17.5 Hz in axial mode and 3.8 Hz in flexion-extension mode. Accordingly, the predicted responses for the cyclic load of −400 ± 40 N applied at four different frequencies (5, 11, 16.5, and 25 Hz) were compared with the corresponding results for axial compressive static loads (−360, and −440 N). As compared to the static load cases, the predicted responses were higher for the cyclic loading. For example, the effect of cyclic load at 11 Hz was to produce significant changes (9.7 – 19.0 percent) in stresses, loads transmitted through the facets, intradiscal pressure (IDP), disk bulge, as compared to the static load predictions. The responses were found to be frequency dependent as well; supporting the in vivo observations of other investigators that the human spine has a resonant frequency. For example, the 11 Hz model (DYN11) compared to the DYN5 model showed an increase in majority of the predicted parameters. The parameters showed an increase with frequency until 17.5 Hz (resonant frequency of the model); thereafter a decrease at 25 Hz. A chronic change in these parameters, especially at the resonant frequency, beyond the “base” values may trigger the bone remodeling process leading to spinal degeneration/disorders associated with chronic vibration exposure. Future directions for extending the present model as a complement to the experimental investigations are also discussed.

scholarly journals In vivo three-dimensional mandibular kinematics and functional point trajectories during temporomandibular activities using 3d fluoroscopy

2020 ◽  
pp. 20190464
Author(s):  
Chien-Chih Chen ◽  
Cheng-Chung Lin ◽  
Hong-Po Hsieh ◽  
Yang-Chieh Fu ◽  
Yunn-Jy Chen ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Mouth Opening ◽  
Three Dimensions ◽  
Forward Movement ◽  
Joint Activities ◽  
End Point ◽  
3D Fluoroscopy ◽  
Point Trajectories ◽  
Functional Point

Objectives: To measure in vivo three-dimensional kinematics of the mandible and associated end-point trajectories and to quantify their relationships during temporomandibular joint activities using 3D fluoroscopy. Methods: A novel fluoroscopy-based 3D measurement method was used to measure motions of the mandible and the associated end points (i.e. incisors and lateral poles of both condyles) during open close, lateral gliding and protrusion-retraction movements in healthy young individuals. The contributions of each of the rotational and translational components of the mandible to the end-point trajectories were quantified through experiment-based computer simulations. Results: The mandibular rotation was found to account for 91% of the maximal mouth-opening-capacity and 73% of the maximal lateral incisor movement, while the condylar translation contributed to 99% of the anterior protrusion distance. Incisor trajectories were nearly vertical within the first 60% of the maximal opening during the open-close movement. Conclusions: Similar condylar downward rotation paths but with bilaterally asymmetrical ranges were used to perform basic mandibular movements of different targeted TI trajectories in three dimensions, that is, open-close, lateral-gliding and protrusion-retraction. Mandibular rotations contributed to the majority of the principal displacement components of the incisor, that is, vertical during open-close and towards the working-side-during lateral-gliding, while mandibular translation contributed mainly to the forward movement of the incisor during protrusion-retraction. Owing to the anatomical constraints, the freedom of mandibular translation is limited and mainly in the anteroposterior direction, which is considered helpful for the control and stability of the TMJ during oral activities.

scholarly journals Comparison of modelling and tracking methods for analysing elbow and forearm kinematics

2019 ◽  
Vol 233 (11) ◽  
pp. 1113-1121 ◽  
Author(s):  
Wei Wang ◽  
Dongmei Wang ◽  
Mariska Wesseling ◽  
Bin Xue ◽  
Feiyue Li
Keyword(s):  
Three Dimensional ◽  
Optimal Estimation ◽  
Elbow Flexion ◽  
Coordinate Systems ◽  
Kinematic Data ◽  
Measurement Protocol ◽  
Flexion Extension ◽  
Good Consistency ◽  
Optical Motion ◽  
Optical Motion Capture

This study aimed to find an optimal measurement protocol of elbow and forearm kinematics using different modelling and tracking methods. Kinematic data of elbow flexion/extension and forearm pronation/supination was acquired using optical motion capture from 12 healthy male volunteers. Segment coordinate systems for humerus, forearm, radius, ulna, and hand were defined. Different tracking methods, using anatomical markers or rigid or point maker clusters, were used to compute the three-dimensional rotations. Marker placement errors were assessed to evaluate the rigid body assumption. Multiple comparisons demonstrated statistical differences between tracking methods: compared to using only anatomical markers, tracking using clusters reduced the estimated range of pronation/supination by 14.9%–43.2%, while it estimated increased flexion/extension by 5.3%–9.1%. The study suggests using only anatomical markers exerts the optimal estimation of elbow and forearm kinematics. Modelling using the coordinate systems of the humerus and forearm and of the humerus and ulna, respectively, demonstrated good consistency with literature and are correspondingly regarded as the most appropriate approach for measuring pronation/supination and flexion/extension. The results are valuable in establishing a measurement protocol for analysing elbow and forearm kinematics, avoiding confusions and misinterpretations in communicating results from different methodologies.

An algorithm for estimation of chromosome motion in Four-Dimensional microscopic images

1994 ◽  
Vol 52 ◽  
pp. 930-931
Author(s):  
Wallace Marshall ◽  
David Agard ◽  
John Sedat
Keyword(s):  
Nuclear Organization ◽  
Three Dimensional ◽  
Estimation Algorithm ◽  
Structural Features ◽  
Random Motion ◽  
Structural Representation ◽  
Functional Roles ◽  
The Face ◽  
Chromosome Motion

Analysis of the three-dimensional organization of chromosomes within the nucleus has revealed a number of characteristic structural features. Yet imaging of living nuclei indicate that chromosomes undergo considerable random motion. Maintenance of nuclear organization in the face of such motion is thought to involve the attachment of chromosomes to the nuclear envelope or matrix. Yet while such attachments have been proposed to play a variety of functional roles as well as maintain nuclear organization, direct evidence for the existence of these mechanical interactions in vivo has been lacking. One way to demonstrate such attachment directly would be to estimate the motion of chromosomes and attempt thereby to demonstrate the presence of fixed points, which would indicate attachment of chromatin to some fixed superstructure.We have previously presented a motion estimation algorithm that is designed for tracking the motion of nonrigid and featureless objects such as chromosomes. This algorithm starts with a structural representation for the set of chromosomes at each time point, and then finds a correspondence between elements of the representations at successive time points.

scholarly journals Ranges of Cervical Intervertebral Disc Deformation During an In Vivo Dynamic Flexion–Extension of the Neck

2017 ◽  
Vol 139 (6) ◽  
Author(s):  
Yan Yu ◽  
Haiqing Mao ◽  
Jing-Sheng Li ◽  
Tsung-Yuan Tsai ◽  
Liming Cheng ◽  
...  
Keyword(s):  
Cervical Spine ◽  
Imaging System ◽  
Human Subjects ◽  
Three Dimensional ◽  
Cervical Disc ◽  
Significant Difference ◽  
Flexion Extension ◽  
Fluoroscopic Imaging ◽  
Magnetic Resonance Imaging Mri

While abnormal loading is widely believed to cause cervical spine disc diseases, in vivo cervical disc deformation during dynamic neck motion has not been well delineated. This study investigated the range of cervical disc deformation during an in vivo functional flexion–extension of the neck. Ten asymptomatic human subjects were tested using a combined dual fluoroscopic imaging system (DFIS) and magnetic resonance imaging (MRI)-based three-dimensional (3D) modeling technique. Overall disc deformation was determined using the changes of the space geometry between upper and lower endplates of each intervertebral segment (C3/4, C4/5, C5/6, and C6/7). Five points (anterior, center, posterior, left, and right) of each disc were analyzed to examine the disc deformation distributions. The data indicated that between the functional maximum flexion and extension of the neck, the anterior points of the discs experienced large changes of distraction/compression deformation and shear deformation. The higher level discs experienced higher ranges of disc deformation. No significant difference was found in deformation ranges at posterior points of all the discs. The data indicated that the range of disc deformation is disc level dependent and the anterior region experienced larger changes of deformation than the center and posterior regions, except for the C6/7 disc. The data obtained from this study could serve as baseline knowledge for the understanding of the cervical spine disc biomechanics and for investigation of the biomechanical etiology of disc diseases. These data could also provide insights for development of motion preservation surgeries for cervical spine.

scholarly journals Three-Dimensional Assessment of Upper Limb Proprioception via a Wearable Exoskeleton

2021 ◽  
Vol 11 (6) ◽  
pp. 2615
Author(s):  
Elisa Galofaro ◽  
Erika D’Antonio ◽  
Fabrizio Patané ◽  
Maura Casadio ◽  
Lorenzo Masia
Keyword(s):  
Neurological Diseases ◽  
Scientific Evidence ◽  
Three Dimensional ◽  
Sensory Information ◽  
Elbow Flexion ◽  
Muscle Spindles ◽  
Shoulder Abduction ◽  
Anatomical Location ◽  
Preferred Direction ◽  
Flexion Extension

Proprioception—the sense of body segment’s position and movement—plays a crucial role in human motor control, integrating the sensory information necessary for the correct execution of daily life activities. Despite scientific evidence recognizes that several neurological diseases hamper proprioceptive encoding with consequent inability to correctly perform movements, proprioceptive assessment in clinical settings is still limited to standard scales. Literature on physiology of upper limb’s proprioception is mainly focused on experimental approaches involving planar setups, while the present work provides a novel paradigm for assessing proprioception during single—and multi-joint matching tasks in a three-dimensional workspace. To such extent, a six-degrees of freedom exoskeleton, ALEx-RS (Arm Light Exoskeleton Rehab Station), was used to evaluate 18 healthy subjects’ abilities in matching proprioceptive targets during combined single and multi-joint arm’s movements: shoulder abduction/adduction, shoulder flexion/extension, and elbow flexion/extension. Results provided evidence that proprioceptive abilities depend on the number of joints simultaneously involved in the task and on their anatomical location, since muscle spindles work along their preferred direction, modulating the streaming of sensory information accordingly. These findings suggest solutions for clinical sensorimotor evaluation after neurological disease, where assessing proprioceptive deficits can improve the recovery path and complement the rehabilitation outcomes.

In Vivo Three-Dimensional Mechanical Actions of Individual Flexor-Pronator Muscles: Role in Elbow Valgus Stability

2008 ◽  
Vol 24 (4) ◽  
pp. 325-332 ◽  
Author(s):  
Jason E. Hsu ◽  
Qiyu Peng ◽  
David A. Schafer ◽  
Jason L. Koh ◽  
Gordon W. Nuber ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Ulnar Collateral Ligament ◽  
Elbow Flexion ◽  
Force Sensor ◽  
Muscle Group ◽  
Collateral Ligament ◽  
Flexor Carpi Radialis ◽  
Pronator Teres ◽  
Flexor Carpi Ulnaris

The flexor-pronator mass is thought to be the primary dynamic valgus stabilizer of the elbow and protects the ulnar collateral ligament. However, in vivo multiaxis actions of individual muscles of the flexor-pronator group and their roles in valgus stability have not been investigated quantitatively. This study tested the hypothesis that individual muscles of the flexor-pronator muscle group produce a significant varus moment that provides elbow valgus stability. The flexor carpi ulnaris, flexor carpi radialis, and pronator teres were selectively activated, and the resulting multiaxis moments at the elbow measured at 0°, 30°, 60°, and 90° of elbow flexion using a six-axis force sensor were analyzed for their role in generating varus moment and protecting the ulnar collateral ligament. Considerable off-axis moments were generated by each muscle tested. Through the range of elbow flexion, the varus moment was the major component of the multiaxis action of the flexor carpi ulnaris (p< .001). The flexor carpi radialis and pronator teres had significant actions as elbow flexors and pronators (p≤ .032); these muscles also had a significant varus contribution at 90° elbow flexion (p≤.019). The results suggest that the flexor-pronator muscle group plays an important role in valgus stability of the elbow. In particular, the flexor carpi ulnaris creates a significant varus moment, which is important in unloading and protecting the ulnar collateral ligament. Rehabilitation and strengthening of the flexor-pronator muscle group may help prevent failure of the ulnar collateral ligament and may also help compensate for a medially insufficient elbow.

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