The Reliability of a New Device Designed to Assess Gastrocnemius Contracture

2002 ◽  
Vol 23 (7) ◽  
pp. 655-660 ◽  
Author(s):  
Justin Greisberg ◽  
John Drake ◽  
Joseph Crisco ◽  
Christopher DiGiovanni
Keyword(s):  
Repeated Measures ◽  
Three Dimensional ◽  
Knee Extension ◽  
Ankle Dorsiflexion ◽  
Repeated Measurements ◽  
Observer Variability ◽  
New Device ◽  
Measuring Devices ◽  
Inter Observer Variability ◽  
Full Knee Extension

Gastrocnemius contracture may be a significant cause of many foot disorders. Gastrocnemius tension can be estimated clinically by measuring maximum ankle dorsiflexion during full knee extension. Such measurements, when made with currently available goniometric devices, are subject to high levels of intra- and inter-observer variability. We have designed a device to more consistently measure ankle dorsiflexion, using three dimensional tracking sensors on the leg and foot. The applied dorsiflexion torque is kept constant by a computer, and the computer also monitors hindfoot position to maintain a neutrally aligned foot during testing. Repeated measurements on 26 feet were taken to determine the consistency of the device. The correlation coefficient for the measurements was 0.96, indicating very low intra- observer variability. The standard deviation of the repeated measures was 2°. Based on the 95% confidence interval, the device can be considered accurate to within 4°. Given this accuracy, this instrument could be used to assess gastrocnemius tension, its role in foot pathology, and the effectiveness of surgical lengthening. Compared to other currently available measuring devices, this instrument is the most reliable in estimating ankle dorsiflexion, since it is capable of controlling hindfoot position and applied dorsiflexion torque, and it can be easily constructed by other laboratories.

Relationship Between Weightbearing Ankle Dorsiflexion Passive Range of Motion and Ankle Kinematics During Gait

2017 ◽  
Vol 107 (1) ◽  
pp. 39-45 ◽  
Author(s):  
Min-Hyeok Kang ◽  
Jae-Seop Oh
Keyword(s):  
Range Of Motion ◽  
Three Dimensional ◽  
Knee Extension ◽  
Ankle Dorsiflexion ◽  
Physically Active ◽  
Ankle Kinematics ◽  
The Difference ◽  
Analysis System ◽  
The Relationship ◽  
Paired T Test

Background: Measurement of weightbearing ankle dorsiflexion (DF) passive range of motion (PROM) has been suggested as a way to estimate ankle kinematics during gait; however, no previous study has demonstrated the relationship between ankle DF during gait and ankle DF PROM with knee extension. We examine the relationship between maximum ankle DF during gait and nonweightbearing and weightbearing ankle DF PROM with knee extension. Methods: Forty physically active individuals (mean ± SD age, 21.63 ± 1.73 years) participated in this study. Ankle DF PROM with knee extension was measured in the nonweightbearing and weightbearing conditions; maximum ankle DF during gait was assessed using a three-dimensional motion analysis system. The relationship between each variable was calculated using the Pearson product moment correlation coefficient, and the difference in ankle DF PROM between the nonweightbearing and weightbearing conditions was analyzed using a paired t test. Results: The weightbearing measurement (r = 0.521; P < .001) for ankle DF PROM showed a greater correlation with maximum ankle DF during gait than did the nonweightbearing measurement (r = 0.245; P = .029). Ankle DF PROM was significantly greater in the weightbearing than in the nonweightbearing condition (P < .001) despite a significant correlation between the two measurements (r = 0.402; P < .001). Conclusions: These findings indicate that nonweightbearing and weightbearing measurements of ankle DF PROM with knee extension should not be used interchangeably and that weightbearing ankle DF PROM with the knee extended is more appropriate for estimating ankle DF during gait.

scholarly journals Biomechanical Analysis of Running in Shoes with Different Heel-to-Toe Drops

2021 ◽  
Vol 11 (24) ◽  
pp. 12144
Author(s):  
Masen Zhang ◽  
Huijuan Shi ◽  
Hui Liu ◽  
Xinglong Zhou
Keyword(s):  
Lower Extremity ◽  
Repeated Measures ◽  
Impact Force ◽  
Three Dimensional ◽  
Knee Extension ◽  
Biomechanical Analysis ◽  
Initial Contact ◽  
Vertical Loading ◽  
Peak Knee ◽  
Running Shoes

The heel-to-toe drop of running shoes is a key parameter influencing lower extremity kinematics during running. Previous studies testing running shoes with lower or larger drops generally used minimalist or maximalist shoes, where the factors outside of the drop may lead to the observed changes in running biomechanics. Therefore, our aim was to compare the strike patterns, impact force, and lower extremity biomechanics when running in shoes that varied only in their drops. Eighteen habitual rearfoot strikers performed trials wearing running shoes with four drop conditions: 15 mm, 10 mm, 5 mm, and without a drop. Three-dimensional (3D) tracks of the reflective markers and impact force were synchronously collected using a video graphic acquisition system and two force plates. The biomechanical parameters were compared among the four drop conditions using one-way ANOVA of repeated measures. A greater foot inclination angle (p = 0.001, ηp2 = 0.36) at initial contact and a lower vertical loading rate (p = 0.002, ηp2 = 0.32) during the standing phase were found when running in shoes with large drops compared with running in shoes without a drop. Running in shoes with large drops, as opposed to without, significantly increased the peak knee extension moment (p = 0.002, ηp2 = 0.27), but decreased the peak ankle eversion moment (p = 0.001, ηp2 = 0.35). These findings suggest that the heel-to-toe drop of running shoes significantly influences the running pattern and the loading on lower extremity joints. Running shoes with large drops may be disadvantageous for runners with knee weakness and advantageous for runners with ankle weakness.

Effect of Different Insole Materials on Kinetic and Kinematic Variables of the Walking Gait in Healthy People

2018 ◽  
Vol 108 (5) ◽  
pp. 390-396 ◽  
Author(s):  
Ramadan Özmanevra ◽  
Salih Angin ◽  
İzge H. Günal ◽  
Ata Elvan
Keyword(s):  
Repeated Measures ◽  
Knee Flexion ◽  
Reaction Force ◽  
Three Dimensional ◽  
Ankle Dorsiflexion ◽  
Healthy People ◽  
Walking Gait ◽  
System A ◽  
Significant Difference ◽  
Analysis System

Background: There is a lack of data that could address the effects of off-the-shelf insoles on gait variables in healthy people. Methods: Thirty-three healthy volunteers ranging in age from 18 to 35 years were included to this study. Kinematic and kinetic data were obtained in barefoot, shoe-only, steel insole, silicone insole, and polyurethane insole conditions using an optoelectronic three-dimensional motion analysis system. A repeated measures analysis of variance test was used to identify statistically significant differences between insole conditions. The alpha level was set at P < .05 Results: Maximum knee flexion was higher in the steel insole condition (P < .0001) compared with the silicone insole (P = .001) and shoe-only conditions (P = .032). Reduced maximum knee flexion was recorded in the polyurethane insole condition compared with the shoe-only condition (P = .031). Maximum knee flexion measured in the steel insole condition was higher compared to the barefoot condition (P = .020). Higher maximum ankle dorsiflexion was observed in the barefoot condition, and there were significant differences between the polyurethane insole (P < .0001), silicone insole (P = .001), steel insole (P = .002), and shoe conditions (P = .004). Least and highest maximum ankle plantarflexion were detected in the steel insole and silicone insole conditions, respectively. Maximum ankle plantarflexion in the barefoot and steel insole conditions (P = .014) and the barefoot and polyurethane insole conditions (P = .035) were significant. There was no significant difference between conditions for ground reaction force or joint moments. Conclusions: Insoles made by different materials affect maximum knee flexion, maximum ankle dorsiflexion, and maximum ankle plantarflexion. This may be helpful during the decision-making process when selecting the insole material for any pathological conditions that require insole prescription.

scholarly journals P275 Feasibility and accuracy of the automated quantification of two- and three-dimensional left ventricular ejection fraction and its role in the arrhythmic risk stratification of organic heart disease

2020 ◽  
Vol 21 (Supplement_1) ◽  
Author(s):  
M Previtero ◽  
N Ruozi ◽  
G Sammarco ◽  
D Azzolina ◽  
R M Tenaglia ◽  
...  
Keyword(s):  
Heart Disease ◽  
Risk Stratification ◽  
Three Dimensional ◽  
Left Ventricular ◽  
Left Ventricular Ejection ◽  
Observer Variability ◽  
Ventricular Ejection Fraction ◽  
Inter Observer Variability ◽  
Organic Heart Disease ◽  
The One

Abstract BACKGROUND New automated approaches for left heart chamber quantification based on adaptive analytics algorithms have been introduced for both two- (2DE) and three-dimensional (3DE) echocardiography. These algorithms measure a left ventricular ejection fraction (LVEF) and reduce the intra- and inter-observer variability associated with the conventional manual tracing of LV endocardial borders. However, the clinical utility of these algorithms in the sudden cardiac death (SCD) risk stratification of patients with organic heart disease remains to be clarified. PURPOSE We sought to test the feasibility and the accuracy of two automated algorithms that measure 2DE and 3DE LVEF in patients with impaired LV systolic function and to define the cut-off values for fully automated 2DE and 3DE LVEF that could predict major arrhythmic events (MAE). We wanted also to assess the feasibility of replacing manual 2DE and semi-automated (SA) 3DE LVEF with fully-automated (FA) 2DE and 3DE LVEF respectively, in the stratification of high arrhythmic risk patients. METHODS We prospectively enrolled 240 patients (63 ± 13 years, 81% men) with both ischemic and non-ischemic cardiomyopathy with 2DE LVEF < 50%, no previous MAE or coronary artery revascularization < 90 days, after at least 3 months of optimal medical therapy for heart failure. MAE were defined as SCD, resuscitated cardiac arrest (CA), ventricular fibrillation, sustained ventricular tachycardia and appropriate ICD shocks. The risk detection cut-off values for 2DE and 3DE FA LVEF were computed using the maximally selected rank statistics method. In order to predict the risk of MAE we created four different risk models, including both clinical characteristics (age, NYHA class, aetiology of the LV dysfunction) and imaging-derived data (2DE manual LVEF, 2DE FA LVEF, 3DE SA LVEF and 3DE FA LVEF), analyzed by a ROC curve. RESULTS During a 27 ± 25months follow-up period, 31 patients (13%) presented MAE including SCD (n= 22; 9%), resuscitated CA (n = 3; 1%) and appropriate ICD shocks (n = 6; 2%). Both 2DE and 3DE FA LVEF showed high feasibility (92% and 95%, respectively), and good agreement with conventional LVEF (2DE mean difference 4 ± 7%, and 3DE mean difference 4 ± 7%). We identified two FA LVEF cut-offs for the MAE detection: 2DE <39% (p = 0.006) and 3DE <37% (p = 0.005). The model including the 2DE FA LVEF showed an area under the curve (AUC) larger than the one including conventional 2DE LVEF (0.83 vs 0.80). Conversely, the AUC obtained with FA 3DE LVEF model was slightly lower than the one obtained using SA 3DE LVEF model (0.80 vs 0.84). CONCLUSIONS Both 2DE and 3DE FA LVEF are feasible and accurate alternative to the conventional (manual) or SA endocardial border tracing. The use of specific FA 2DE LVEF cut-off values showed a comparable predictive power in the MAE risk stratification compared to the conventional one with the advantage of very low intra- and inter-observer variability.

The Influence of Different Force and Pressure Measuring Transducers on Lower Extremity Kinematics Measured During Running

2014 ◽  
Vol 30 (1) ◽  
pp. 166-172 ◽  
Author(s):  
Jonathan Sinclair ◽  
Sarah J. Hobbs ◽  
Paul J. Taylor ◽  
Graham Currigan ◽  
Andrew Greenhalgh
Keyword(s):  
Repeated Measures ◽  
Force Plate ◽  
Three Dimensional ◽  
Measuring Transducer ◽  
Camera Motion ◽  
Gait Patterns ◽  
3 Dimensional ◽  
Measuring Devices ◽  
Analysis System ◽  
Camera Motion Analysis

In running analyses where both kinetic and kinematic information is recorded, participants are required to make foot contact with a force and/or pressure measuring transducer. Problems arise if participants modify their gait patterns to ensure contact with the device. There is currently a paucity of research investigating the influence of different underfoot kinetic measuring devices on 3-dimensional kinematics of running. Fifteen participants ran at 4.0 m/s in four different conditions: over a floor embedded force plate, Footscan, Matscan, and with no device. Three-dimensional angular kinematic parameters were collected using an eight camera motion analysis system. Hip, knee, and ankle joint kinematics were contrasted using repeated-measures ANOVAs. Participants also rated their subjective comfort in striking each of the three force measuring devices. Significant differences from the uninhibited condition were observed using the Footscan and Matscan in all three planes of rotation, whereas participants subjectively rated the force plate significantly more comfortable than either the Footscan/Matscan devices. The findings of the current investigation therefore suggest that the disguised floor embedded force plate offers the most natural running condition. It is recommended that analyses using devices such as the Footscan/Matscan mats overlying the laboratory surface during running should be interpreted with caution.

scholarly journals Robust Resolution-Enhanced Prostate Segmentation in Magnetic Resonance and Ultrasound Images through Convolutional Neural Networks

2021 ◽  
Vol 11 (2) ◽  
pp. 844
Author(s):  
Oscar J. Pellicer-Valero ◽  
Victor Gonzalez-Perez ◽  
Juan Luis Casanova Ramón-Borja ◽  
Isabel Martín García ◽  
María Barrios Benito ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Resolution Enhancement ◽  
Three Dimensional ◽  
3D Ultrasound ◽  
Lesion Detection ◽  
Dice Similarity Coefficient ◽  
Ultrasound Images ◽  
Observer Variability ◽  
Prostate Segmentation ◽  
Inter Observer Variability

Prostate segmentations are required for an ever-increasing number of medical applications, such as image-based lesion detection, fusion-guided biopsy and focal therapies. However, obtaining accurate segmentations is laborious, requires expertise and, even then, the inter-observer variability remains high. In this paper, a robust, accurate and generalizable model for Magnetic Resonance (MR) and three-dimensional (3D) Ultrasound (US) prostate image segmentation is proposed. It uses a densenet-resnet-based Convolutional Neural Network (CNN) combined with techniques such as deep supervision, checkpoint ensembling and Neural Resolution Enhancement. The MR prostate segmentation model was trained with five challenging and heterogeneous MR prostate datasets (and two US datasets), with segmentations from many different experts with varying segmentation criteria. The model achieves a consistently strong performance in all datasets independently (mean Dice Similarity Coefficient -DSC- above 0.91 for all datasets except for one), outperforming the inter-expert variability significantly in MR (mean DSC of 0.9099 vs. 0.8794). When evaluated on the publicly available Promise12 challenge dataset, it attains a similar performance to the best entries. In summary, the model has the potential of having a significant impact on current prostate procedures, undercutting, and even eliminating, the need of manual segmentations through improvements in terms of robustness, generalizability and output resolution.

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