scholarly journals Kinematics or Kinetics: Optimum Measurement of the Vertical Variations of the Center of Mass during Gait Initiation

Sensors ◽  
2021 ◽  
Vol 21 (23) ◽  
pp. 7954
Author(s):  
Antoine Langeard ◽  
Charlotte Mathon ◽  
Mourad Ould-Slimane ◽  
Leslie Decker ◽  
Nicolas Bessot ◽  
...  
Keyword(s):  
Motion Capture ◽  
Center Of Mass ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Minimal Detectable Change ◽  
Intraclass Correlation Coefficients ◽  
Kinematic Method ◽  
Risk Of Falls ◽  
Vertical Variations

Background: During gait, the braking index represents postural control, and consequently, the risk of falls. Previous studies based their determination of the braking index during the first step on kinetic methods using force platforms, which are highly variable. This study aimed to investigate whether determining the braking index with a kinematic method, through 3D motion capture, provides more precise results. Methods: Fifty participants (20 to 40 years) performed ten trials in natural and fast gait conditions. Their braking index was estimated from their first step simultaneously using a force platform and VICON motion capture system. The reliability of each braking index acquisition method was assessed by intraclass correlation coefficients, standard error measurements, and the minimal detectable change. Results: Both kinetic and kinematic methods allowed good to excellent reliability and similar minimum detectable changes (10%). Conclusion: Estimating the braking index through a kinetic or a kinematic method was highly reliable.

scholarly journals Interday Reliability and Usefulness of a Reactive Strength Index Derived From 2 Maximal Rebound Jump Tests

2019 ◽  
Vol 14 (9) ◽  
pp. 1200-1204
Author(s):  
Thomas M. Comyns ◽  
Eamonn P. Flanagan ◽  
Sean Fleming ◽  
Evan Fitzgerald ◽  
Damian J. Harper
Keyword(s):  
Female Athletes ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Strength Index ◽  
Warm Up ◽  
Intraclass Correlation Coefficients ◽  
Jump Test ◽  
Moderate Change ◽  
Familiarization Session

Purpose: To examine the interday reliability and usefulness of a reactive strength index (RSI) derived from a maximal 5-rebound jump test (5max RJT) and a maximal 10-rebound jump test (10/5 RJT). Methods: Twenty male field-sport athletes (24.5 [3.0] y, 1.78 [0.1] m, 84.9 [5.2] kg) and 15 female participants (21.1 [0.9] y, 1.65 [0.73] m, 62.0 [5.1] kg) performed 2 maximal repetitions of the 5max RJT and the 10/5 RJT on 2 testing days after a specific warm-up. A 1-wk period separated testing days, and these sessions were preceded by a familiarization session. RSI was calculated by dividing jump height (in meters) by contact time (in seconds). The 5max RJT and the 10/5 RJT trial with the highest RSI on each testing day were used for reliability and usefulness analysis. Results: Both tests were deemed reliable for determining RSI for male, female, and pooled male and female cohorts, as the intraclass correlation coefficients were ≥.80 and the coefficient of variation was ≤10%. Only the 5max RJT was rated as “good” at detecting the smallest worthwhile change in performance for female athletes (smallest worthwhile change: 0.10 > typical error: 0.07). The 5max RJT for men and the 10/5 RJT for men and women were rated “good” in detecting a moderate change in performance only. Conclusions: Both tests are reliable for the determination of RSI, but the usefulness of the tests in detecting the smallest worthwhile change is questionable.

Genetic variation in the quantitative levels of an NADP (H)-binding protein (FX) in human erythrocytes

Blood ◽  
1981 ◽  
Vol 57 (2) ◽  
pp. 209-217 ◽  
Author(s):  
L Lenzerini ◽  
U Benatti ◽  
A Morelli ◽  
S Pontremoli ◽  
A De Flora ◽  
...  
Keyword(s):  
Genetic Variation ◽  
Preliminary Data ◽  
Binding Protein ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Red Cell ◽  
Genetic Origin ◽  
Intraclass Correlation Coefficients ◽  
The Individual

Abstract FX is a red cell NADP(H)-binding protein that has been well defined biochemically and immunologically but whose function is still unknown. Preliminary data indicated that the levels of this protein are significantly increased in hemizygotes, heterozygotes, and homozygotes for the G6PD Mediterranean mutant, thus raising the question of whether or not the individual variation in FX levels is more or less directly influenced by X-linked genes. The present study, based on a large series of population and family data collected in Sardinia, confirms unequivocally the above mentioned interaction, but shows at the same time that the variances in FX levels “between sibships” are 2–3 times larger than those “within sibships,” when the analysis is done separately for the G6PD-normal or the G6PD-deficient sibs. From the comparison of the interclass and intraclass correlation coefficients, it appears that about 60% of the total variation of FX is of genetic origin. Moreover, the FX levels of children, analyzed in a pairwise manner, were found to be more positively correlated with those of their fathers (r = 0.39) than with those of their maternal grandfathers (0.20). This latter finding obviously favors the conclusion that “autosomal”; rather than “X-linked” genes are involved in the determination of the FX levels.

scholarly journals Test-retest reliability and minimal detectable change of the Balance Evaluation Systems Test and its two abbreviated versions in persons with mild to moderate spinocerebellar ataxia: A pilot study

2020 ◽  
Vol 47 (4) ◽  
pp. 479-486
Author(s):  
Yuki Kondo ◽  
Kyota Bando ◽  
Yosuke Ariake ◽  
Wakana Katsuta ◽  
Kyoko Todoroki ◽  
...  
Keyword(s):  
Spinocerebellar Ataxia ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Minimal Detectable Change ◽  
Detectable Change ◽  
Retest Reliability ◽  
Evaluation Systems ◽  
Intraclass Correlation Coefficients ◽  
Interclass Correlation ◽  
Test Retest Reliability

BACKGROUND: The reliability of the evaluation of the Balance Evaluation Systems Test (BESTest) and its two abbreviated versions are confirmed for balance characteristics and reliability. However, they are not utilized in cases of spinocerebellar ataxia (SCA). OBJECTIVE: We aimed to examine the test-retest reliability and minimal detectable change (MDC) of the BESTest and its abbreviated versions in persons with mild to moderate spinocerebellar ataxia. METHODS: The BESTest was performed in 20 persons with SCA at baseline and one month later. The scores of the abbreviated version of the BESTest were determined from the BESTest scores. The interclass correlation coefficient (1,1) was used as a measure of relative reliability. Furthermore, we calculated the MDC in the BESTest and its abbreviated versions. RESULTS: The intraclass correlation coefficients (1,1) and MDC at 95% confidence intervals were 0.92, 8.7(8.1%), 0.91, 4.1(14.5%), and 0.81, 5.2(21.6%) for the Balance, Mini-Balance, and Brief-Balance Evaluation Systems Tests, respectively. CONCLUSIONS: The BESTest and its abbreviated versions had high test-retest reliability. The MDC values of the BESTest could enable clinicians and researchers to interpret changes in the balance of patients with SCA more precisely.

Determination of Facial Symmetry in Unilateral Cleft Lip and Palate Patients from Three-Dimensional Data: Technical Report and Assessment of Measurement Errors

2006 ◽  
Vol 43 (2) ◽  
pp. 129-137 ◽  
Author(s):  
Emeka Nkenke ◽  
Bernhard Lehner ◽  
Manuel Kramer ◽  
Gerd Haeusler ◽  
Stefanie Benz ◽  
...  
Keyword(s):  
Measurement Errors ◽  
Cleft Lip ◽  
Cleft Lip And Palate ◽  
Intraclass Correlation ◽  
Three Dimensional ◽  
Correlation Coefficients ◽  
Intraclass Correlation Coefficients ◽  
Surface Areas ◽  
Technical Report

Objective To assess measurement errors of a novel technique for the three-dimensional determination of the degree of facial symmetry in patients suffering from unilateral cleft lip and palate malformations. Design Technical report, reliability study. Setting Cleft Lip and Palate Center of the University of Erlangen-Nuremberg, Erlangen, Germany. Patients The three-dimensional facial surface data of five 10-year-old unilateral cleft lip and palate patients were subjected to the analysis. Distances, angles, surface areas, and volumes were assessed twice. Main Outcome Measures Calculations were made for method error, intraclass correlation coefficient, and repeatability of the measurements of distances, angles, surface areas, and volumes. Results The method errors were less than 1 mm for distances and less than 1.5° for angles. The intraclass correlation coefficients showed values greater than .90 for all parameters. The repeatability values were comparable for cleft and noncleft sides. Conclusion The small method errors, high intraclass correlation coefficients, and comparable repeatability values for cleft and noncleft sides reveal that the new technique is appropriate for clinical use.

Reliability and Validity of a Wireless Accelerometer for the Assessment of Postural Sway

2015 ◽  
Vol 31 (3) ◽  
pp. 159-163 ◽  
Author(s):  
Nathan W. Saunders ◽  
Panagiotis Koutakis ◽  
Anne D. Kloos ◽  
Deborah A. Kegelmeyer ◽  
Jessica D. Dicke ◽  
...  
Keyword(s):  
Postural Sway ◽  
Center Of Mass ◽  
Intraclass Correlation ◽  
Reliability And Validity ◽  
Correlation Coefficients ◽  
Discrimination Capability ◽  
Intraclass Correlation Coefficients ◽  
Balance Task ◽  
Eyes Open ◽  
Test Retest Reliability

Clinicians are in need of valid and objective measures of postural sway. Accelerometers have been shown to be suitable alternatives to expensive and stationary force plates. We evaluated the test-retest reliability and balance task discrimination capability of a new wireless triaxial accelerometer (YEI 3-Space Sensor). Four testing conditions (eyes open or closed, while on a firm or compliant surface) were used to progressively challenge the static balance of 20 healthy male (n = 8) and female (n = 12) older adults (mean age 81 ± 4.3 y). Subjects completed 2 blocks of three 30-second trials per condition. The accelerometer was positioned on the lower back to acquire mediolateral (M-L) and anterior-posterior (A-P) accelerations. Intraclass correlation coefficients were all good to excellent, with values ranging from .736 to .972 for trial-to-trial and from .760 to .954 for block-to-block. A significant stepwise increase in center of mass acceleration root mean square values was found across the 4 balance conditions (F[1.49, 28.26] = 39.54, P < .001). The new accelerometer exhibited good to excellent trial-to-trial and block-to-block reliability and was sensitive to differences in visual and surface conditions and acceleration axes.

scholarly journals Reliability of the ForceFrame With and Without a Fixed Upper-Limb Mold in Shoulder Rotation Strength Assessments Compared With Traditional Hand-Held Dynamometry

2021 ◽  
pp. 1-4
Author(s):  
Jamon Couch ◽  
Marc Sayers ◽  
Tania Pizzari
Keyword(s):  
Upper Limb ◽  
External Rotation ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Shoulder Abduction ◽  
Minimal Detectable Change ◽  
Retest Reliability ◽  
Intraclass Correlation Coefficients ◽  
Shoulder Strength ◽  
Test Retest Reliability

Context: An imbalance between shoulder internal rotation (IR) and external rotation (ER) strength in athletes is proposed to increase the risk of sustaining a shoulder injury. Hand-held (HHD) and externally fixed dynamometry are reliable forms of assessing shoulder IR and ER strength. A new externally fixed device with an attachable fixed upper-limb mold (The ForceFrame) exists; however, its reliability in measuring shoulder strength is yet to be investigated. Objective: To determine the test–retest reliability of the ForceFrame, with and without the fixed upper-limb mold, in the assessment of shoulder IR and ER strength, as compared with HHD. Design: Test–retest reliability study. Setting: Laboratory, clinical. Participants: Twenty-two healthy and active individuals were recruited from the university community and a private physiotherapy practice. Main Outcome Measures: Maximal isometric shoulder IR and ER strength was measured using the ForceFrame and traditional HHD in neutral and at 90° shoulder abduction. Mean (SD) strength measures were calculated. Test–retest reliability was analyzed using intraclass correlation coefficients (3, 1). The SEM and minimal detectable change were calculated. Results: Good to excellent test–retest reliability was found for all shoulder strength tests across Hand-held dynamometry (HHD) and externally fixed dynamometry (EFD) are reliable forms (intraclass correlation coefficients [3, 1] = .854–.916). The minimal detectable changes ranged between 25.61 and 41.84 N across tests. Test–retest reliability was not affected by the dynamometer or testing position. Conclusions: The results from this study indicate that both the ForceFrame and HHD are suitable for measuring shoulder strength in clinical practice. The use of the fixed upper-limb mold with the ForceFrame does not improve reliability.

Evaluating Intratester Reliability of Manual Masking of Plantar Pressure Measurements Associated with Chronic Gout

2011 ◽  
Vol 101 (5) ◽  
pp. 424-429
Author(s):  
Keith Rome ◽  
David George Survepalli ◽  
Maria Lobo ◽  
Nicola Dalbeth ◽  
Fiona McQueen ◽  
...  
Keyword(s):  
Plantar Pressure ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Minimal Detectable Change ◽  
Pressure Measurements ◽  
Detectable Change ◽  
Limits Of Agreement ◽  
Intraclass Correlation Coefficients ◽  
Chronic Gout ◽  
Pressure Time

Background: Plantar pressure measurements are commonly used to evaluate foot function in chronic musculoskeletal conditions. However, manually identifying anatomical landmarks is a source of measurement error and can produce unreliable data. The aim of this study was to evaluate intratester reliability associated with manual masking of plantar pressure measurements in patients with gout. Methods: Twenty-five patients with chronic gout (mean disease duration, 22 years) were recruited from rheumatology outpatient clinics. Patients were excluded if they were experiencing an acute gout flare at the time of assessment, had lower-limb amputation, or had diabetes mellitus. Manual masking of peak plantar pressures and pressure-time integrals under ten regions of the foot were undertaken on two occasions on the same day using an in-shoe pressure measurement system. Test-retest reliability was assessed by using intraclass correlation coefficients, SEM, 95% limits of agreement, and minimal detectable change. Results: Mean peak pressure intraclass correlation coefficients ranged from 0.92 to 0.97, with SEM of 8% to 14%. The 95% limits of agreement ranged from−150.3 to 133.5 kPa, and the minimal detectable change ranged from 30.8 to 80.6 kPa. For pressure-time integrals, intraclass correlation coefficients were 0.86 to 0.94, and SEM were 5% to 29%, with the greater errors observed under the toes. The 95% limits of agreement ranged from −48.5 to 48.8 kPa/sec, and the minimal detectable change ranged from 6.8 to 21.0 kPa/sec. Conclusions: These findings provide clinicians with information confirming the errors associated with manual masking of plantar pressure measurements in patients with gout. (J Am Podiatr Med Assoc 101(5): 424–429, 2011)

scholarly journals Intrasession and Intersession Reliability of Isometric Trunk and Hip Strength Measurements Using the Portable Tension Dynamometer

2021 ◽  
pp. 1-4
Author(s):  
Sakiko Oyama ◽  
Edgar Garza ◽  
Kylie Dugan
Keyword(s):  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Minimal Detectable Change ◽  
Detectable Change ◽  
Leg Length ◽  
Trunk Flexion ◽  
Hip Strength ◽  
Intraclass Correlation Coefficients ◽  
Hip Abduction ◽  
Abduction Strength

Context: The trunk/pelvis is an important link between the upper- and lower-extremities. Therefore, assessing strength of the trunk and hip muscles that control the segments is clinically meaningful. While an isokinetic dynamometer can be used to measure trunk strength, the equipment is expensive and not portable. Objective: To test the reliability of simple trunk and hip strength measures that utilize a bar, straps, and a portable tension dynamometer. Design: Test–retest reliability study. Setting: Biomechanics research laboratory. Patients (or Other Participants): Twenty college-age individuals (10 males/10 females, age = 20.9 [3.7] y) participated. Intervention(s): The participants attended 2 testing sessions, 1 week apart. The participants’ trunk-flexion, rotation, and hip abduction strength were measured at each session. Main Outcome Measures: Peak trunk flexion, rotation, and hip abduction forces were normalized to the participant’s body weight (BW). In addition, hip-abduction torque was calculated by multiplying the force times the leg length and normalized to BW. The trial data from both sessions were used to calculate the intrasession reliability, and the averages from the 2 sessions were used to calculate the intersession reliability. Intraclass correlation coefficients, SEM, and minimal detectable change were calculated to evaluate reliability of measures. Results: The intrasession intraclass correlation coefficients (SEM) for trunk flexion, rotation, hip abduction, and hip abduction torque were .837 (5.2% BW), .978 (1.3% BW), .955 (1.0% BW), and .969 (5.8 N·m/BW), respectively. The intersession reliability for trunk flexion, rotation, hip abduction, and hip abduction torque were .871 (4.3% BW), .801 (3.8% BW), .894 (1.5% BW), and .968 (5.9 N·m/BW), respectively. Conclusions: The measures of trunk and hip abduction strength are highly repeatable within a session. The reliability of the measures between sessions was also good/excellent with relatively small SEM and minimal detectable change. The tests described in this study can be used to assess changes in trunk/hip strength over time.

scholarly journals Association Between Markerless Motion Capture Screenings and Musculoskeletal Injury Risk for Military Trainees: A Large Cohort and Reliability Study

2021 ◽  
Vol 9 (10) ◽  
pp. 232596712110416
Author(s):  
Ben R. Hando ◽  
W. Casan Scott ◽  
Jacob F. Bryant ◽  
Juste N. Tchandja ◽  
Ryan M. Scott ◽  
...  
Keyword(s):  
Lower Extremity ◽  
Motion Capture ◽  
Injury Risk ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Musculoskeletal Injury ◽  
Retest Reliability ◽  
Intraclass Correlation Coefficients ◽  
Markerless Motion Capture ◽  
Test Retest Reliability

Background: Markerless motion capture (MMC) systems used to screen for musculoskeletal injury (MSKI) risk have become popular in military and collegiate athletic settings. However, little is known regarding the test-retest reliability or, more importantly, the ability of these systems to accurately identify individuals at risk for MSKI. Purpose: To determine the association between scores from a proprietary MMC movement screen test and the likelihood of suffering a subsequent MSKI and establish the test-retest reliability of the MMC system used. Study Design: Cohort study; Level of evidence, 3. Methods: Trainees for the Air Force Special Warfare program underwent MMC screenings immediately before entering the 8-week training course. MSKI data were extracted from a database for the surveillance period for each trainee. Logistic regression analyses were performed to identify associations between baseline MMC scores and the likelihood of suffering any MSKI or, specifically, a lower extremity MSKI. The test-retest portion of the study collected MMC scores from 10 separate participants performing 4 trials of the standard test procedures. Reliability was assessed using intraclass correlation coefficients by a single rater. Results: Overall, 1570 trainees, of whom 800 (51%) suffered an MSKI, were included in the analysis. MMC scores poorly predicted the likelihood of any or a lower extremity MSKI (odds ratio, 1.01-1.02). Further, receiver operating characteristic curve analyses demonstrated poor sensitivity and specificity for prediction of MSKI with MMC scores (area under the curve = 0.53). Finally, intraclass correlation coefficients from the test-retest analysis of MMC scores ranged from 0.157 to 0.602. Conclusion: This MMC system displayed poor to moderate test-retest reliability and did not demonstrate the ability to discriminate between individuals who were and were not likely to suffer an MSKI.

Validity of the Open Barbell and Tendo Weightlifting Analyzer Systems Versus the Optotrak Certus 3D Motion-Capture System for Barbell Velocity

2019 ◽  
Vol 14 (4) ◽  
pp. 540-543 ◽  
Author(s):  
Jacob A. Goldsmith ◽  
Cameron Trepeck ◽  
Jessica L. Halle ◽  
Kristin M. Mendez ◽  
Alex Klemp ◽  
...  
Keyword(s):  
Motion Capture ◽  
Analysis Of Variance ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Motion Capture System ◽  
Training Experience ◽  
Warm Up ◽  
3 Dimensional ◽  
Intraclass Correlation Coefficients ◽  
3D Motion Capture

Purpose: To examine the validity of 2 linear position transducers, the Tendo Weightlifting Analyzer System (TWAS) and Open Barbell System (OBS), compared with a criterion device, the Optotrak Certus 3-dimensional motion-capture system (OC3D). Methods: A total of 25 men (age, 25 [3] y; height, 174.0 [6.7] cm; body mass, 89.0 [14.7] kg; squat 1-repetition maximum [1RM], 175.8 [34.7] kg) with ≥2 y of resistance-training experience completed a back 1RM and 1 set to failure at 70% of 1RM. Average concentric velocity (ACV) and peak concentric velocity (PCV) were recorded by all 3 devices during the final warm-up set, all 1RM attempts, and every repetition during the 70% set. Results: In total, 575 samples were obtained. Bland–Altman plots, mountain plots, a 1-way analysis of variance, SEM, and intraclass correlation coefficients were used to analyze validity. The analysis of variance showed no difference (P = .089) between devices for ACV. However, for PCV, TWAS was significantly different (ie, inaccurate) from OC3D (P < .001) and OBS (P = .001), but OBS was similar (P = .412) to OC3D. For ACV, intraclass correlation coefficients were higher for OBS than for TWAS. Bland–Altman plots showed agreement for ACV for both devices against OC3D but large limits of agreement for PCV for both devices. Mountain plots showed valid ACV for both devices, however, but slightly greater ACV and PCV accuracy with OBS than TWAS. Conclusions: Both devices may provide valid ACV measurements, but some metrics suggest more accurate ACV with OBS vs TWAS. For PCV, neither device is particularly accurate; however, OBS seems to be more accurate than TWAS.

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