scholarly journals Errors Associated With Utilizing Prescribed Scapular Kinematics to Estimate Unconstrained, Natural Upper Extremity Motion in Musculoskeletal Modeling

2017 ◽  
Vol 33 (6) ◽  
pp. 469-473 ◽  
Author(s):  
R. Tyler Richardson ◽  
Elizabeth A. Rapp ◽  
R. Garry Quinton ◽  
Kristen F. Nicholson ◽  
Brian A. Knarr ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Musculoskeletal Modeling ◽  
Motion Model ◽  
Scapular Kinematics ◽  
Unconstrained Model ◽  
Research Questions ◽  
Extremity Motion ◽  
Kinematic Errors ◽  
Scapular Motion ◽  
Forward Reach

Musculoskeletal modeling is capable of estimating physiological parameters that cannot be directly measured, however, the validity of the results must be assessed. Several models utilize a scapular rhythm to prescribe kinematics, yet it is unknown how well they replicate natural scapular motion. This study evaluated kinematic errors associated with a model that employs a scapular rhythm using 2 shoulder movements: abduction and forward reach. Two versions of the model were tested: the original MoBL ARMS model that utilizes a scapular rhythm, and a modified MoBL ARMS model that permits unconstrained scapular motion. Model estimates were compared against scapulothoracic kinematics directly measured from motion capture. Three-dimensional scapulothoracic resultant angle errors associated with the rhythm model were greater than 10° for abduction (mean: 16.4°, max: 22.4°) and forward reach (mean: 11.1°, max: 16.5°). Errors generally increased with humerothoracic elevation with all subjects reporting greater than 10° differences at elevations greater than 45°. Errors associated with the unconstrained model were less than 10°. Consequently, use of the original MoBL ARMS model is cautioned for applications requiring precise scapulothoracic kinematics. These findings can help determine which research questions are suitable for investigation with these models and assist in contextualizing model results.

Spatial Kinematic Analysis of the Upper Extremity Using a Biplanar Videotaping Method

1981 ◽  
Vol 103 (1) ◽  
pp. 11-17 ◽  
Author(s):  
N. A. Langrana
Keyword(s):  
Upper Extremity ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Assistive Device ◽  
Kinematic Data ◽  
Computer Aided ◽  
Extremity Motion ◽  
Accuracy And Repeatability ◽  
Three Dimensional Space

A biplanar videotaping system is used to generate spatial kinematic data of an upper extremity motion. The technique is based upon the characterization of each segment by four points in three-dimensional space using biplanar videotaping and subsequent analysis by computer-aided descriptive geometry. The tests were conducted to determine the system’s accuracy and repeatability. The results of the joint kinematics of the test subjects performing a diagonal reaching activity with and without an orthosis (or an assistive device) are presented.

scholarly journals Scapular Dyskinesis: From Basic Science to Ultimate Treatment

2020 ◽  
Vol 17 (8) ◽  
pp. 2974 ◽  
Author(s):  
Longo Umile Giuseppe ◽  
Risi Ambrogioni Laura ◽  
Alessandra Berton ◽  
Vincenzo Candela ◽  
Carlo Massaroni ◽  
...  
Keyword(s):  
Scapular Dyskinesis ◽  
Clinical Tests ◽  
High Quality ◽  
Scapular Kinematics ◽  
Multiple Factors ◽  
Comprehensive Search ◽  
Shoulder Kinematics ◽  
And Function ◽  
Shoulder Pathologies ◽  
Scapular Motion

Background: This study intends to summarize the causes, clinical examination, and treatments of scapular dyskinesis (SD) and to briefly investigate whether alteration can be managed by a precision rehabilitation protocol planned on the basis of features derived from clinical tests. Methods: We performed a comprehensive search of PubMed, Cochrane, CINAHL and EMBASE databases using various combinations of the keywords “Rotator cuff”, “Scapula”, “Scapular Dyskinesis”, “Shoulder”, “Biomechanics” and “Arthroscopy”. Results: SD incidence is growing in patients with shoulder pathologies, even if it is not a specific injury or directly related to a particular injury. SD can be caused by multiple factors or can be the trigger of shoulder-degenerative pathologies. In both cases, SD results in a protracted scapula with the arm at rest or in motion. Conclusions: A clinical evaluation of altered shoulder kinematics is still complicated. Limitations in observing scapular motion are mainly related to the anatomical position and function of the scapula itself and the absence of a tool for quantitative SD clinical assessment. High-quality clinical trials are needed to establish whether there is a possible correlation between SD patterns and the specific findings of shoulder pathologies with altered scapular kinematics.

INTRA- AND INTER-EXAMINER RELIABILITY OFIN VIVOTHREE-DIMENSIONAL MEASUREMENT OF THE SCAPULAR POSES USING A MARKER-BASED LOCATOR

2018 ◽  
Vol 30 (01) ◽  
pp. 1850001
Author(s):  
Mei-Ying Kuo ◽  
Shih-Wun Hong ◽  
Jia-Da Li ◽  
Tung-Wu Lu ◽  
Horng-Chaung Hsu
Keyword(s):  
Tracking System ◽  
Three Dimensional ◽  
Optical Tracking ◽  
Optical Tracking System ◽  
Rater Reliability ◽  
Reliability Models ◽  
Scapular Kinematics ◽  
Dimensional Measurement ◽  
Shoulder Flexion ◽  
Shoulder Complex

Accurate measurement of the three-dimensional scapular kinematics is essential for a better understanding of the mechanical interactions between the scapula and the other segments of the shoulder complex. The purposes of the study were: (i) to development a marker-based scapular locator for measuring scapular poses, and (ii) to determine the intra- and inter-rater reliability of the locator in terms of intra-class correlations (ICC). Twenty-two healthy volunteers without shoulder pathologies participated in the current study. Each subject was tested separately by two raters using the marker-based scapular locator while performing static shoulder flexion at 20, 40, 60, 80, 100 and 120 degrees in the scapular plane. Two reliability models, ICC[Formula: see text] and ICC[Formula: see text], were used to analyze the intra- and inter-rater reliability for scapular rotations and translations. Good to excellent intra-user reliability for both examiners was found for the scapular rotations (range: 0.82–0.99) and displacements (range: 0.72–0.99) for different shoulder flexion conditions. Good to excellent inter-rater reliability was found for scapular rotations (range: 0.63–0.95) and translations (range: 0.70–0.95) for all conditions. The results showed that high intra- and inter-examiner reliability could be achieved for scapular rotations and translation using the marker-based scapular locator. The proposed new scapular locator with an optical tracking system will be helpful for future applications in basic and clinical studies of the shoulder complex during arm movements.

Three-Dimensional Scapular Kinematics during the Throwing Motion

2008 ◽  
Vol 24 (1) ◽  
pp. 24-34 ◽  
Author(s):  
Kristin E. Meyer ◽  
Erin E. Saether ◽  
Emily K. Soiney ◽  
Meegan S. Shebeck ◽  
Keith L. Paddock ◽  
...  
Keyword(s):  
Internal Rotation ◽  
Glenohumeral Joint ◽  
External Rotation ◽  
Angular Position ◽  
Three Dimensional ◽  
Low Velocity ◽  
Dynamic Activity ◽  
Motion Data ◽  
Asymptomatic Subjects ◽  
Scapular Motion

Proper scapular motion is crucial for normal shoulder mechanics. Scapular motion affects glenohumeral joint function during throwing, yet little is known about this dynamic activity. Asymptomatic subjects (10 male and 10 female), ages 21 to 45, were analyzed. Electromagnetic surface sensors on the sternum, acromion, and humerus were used to collect 3-D motion data during three trials of low-velocity throwing. Scapular angular position data were described for five predetermined events throughout the throw corresponding with classic descriptions of throwing phases, and trial-to-trial reliability was determined. ANOVA compared scapular angles across events. Subjects demonstrated good to excellent reliability between trials of the throw (ICC 0.74–0.98). The scapula demonstrated a pattern of external rotation, upward rotation (peak of approx. 40°), and posterior tilting during the initial phases of the throw, progressing into internal rotation after maximum humeral horizontal abduction. During the arm acceleration phase, the scapula moved toward greater internal rotation and began anteriorly tilting. At maximum humeral internal rotation, the scapula ended in internal rotation (55°), upward rotation (20°), and anterior tilting (3°).

Three-Dimensional Analysis of Divergence Aangle on Deposition of Chromium Atoms in Laser Standing Wave Field

2013 ◽  
Vol 562-565 ◽  
pp. 1033-1036
Author(s):  
Jing Huang ◽  
Bao Hu Zhu ◽  
Wen Tao Zhang
Keyword(s):  
Dimensional Analysis ◽  
Standing Wave ◽  
Atomic Beam ◽  
Laser Field ◽  
Three Dimensional ◽  
Motion Model ◽  
Atom Beam ◽  
Standing Wave Field ◽  
Wave Laser ◽  
Beam Divergence Angle

Three-dimensional analysis of the effects of atom beam divergence angle on the process of fabricating nanograting is discussed based on the three-dimensional motion model of Cr atoms in Gaussian standing wave laser field. From the simulative results it can be seen that Atomic beam spreading plays an important role in determining the deposition nanometer quality, so the preparation of a high-collimated and transversely cooled atomic beam, typically under 0.6mrad, is essential to minimize the severely disadvantageous effects for deposition of atoms in laser standing wave

A Measurement of the Adaptation of Color Vision to the Spectral Environment

1997 ◽  
Vol 8 (2) ◽  
pp. 130-134 ◽  
Author(s):  
Steven M. Boker
Keyword(s):  
Maximum Likelihood ◽  
Visual System ◽  
Goodness Of Fit ◽  
Factor Model ◽  
Dimensional Space ◽  
Color Space ◽  
Three Dimensional ◽  
Color Matching ◽  
Four Dimensions ◽  
Unconstrained Model

An exploratory factor analysis of the reflectance spectral distributions of a sample of natural and man-made objects yields a factor pattern remarkably similar to psychophysical color-matching curves. The goodness-of-fit indices from a maximum likelihood confirmatory factor model with fixed factor loadings specified by empirical trichromatic color-matching data indicate that the human visual system performs near to an optimum value for an ideal trichromatic system composed of three linear components. An unconstrained four-factor maximum likelihood model fits significantly better than a three-factor unconstrained model, suggesting that a color metric is better represented in four dimensions than in a three-dimensional space. This fourth factor can be calculated as a nonlinear interaction term between the first three factors: thus, a trichromatic input is sufficient to compute a color space of four dimensions. The visual system may exploit this nonlinear dependency in the spectral environment in order to obtain a four-dimensional color space without the biological cost of a fourth color receptor.

Sign in / Sign up

Export Citation Format

Share Document