scholarly journals Comparison of Accuracy for HKA by X-ray and Knee Motion Analysis System and the Relationships between HKA and Gait Posture

2021 ◽  
Author(s):  
Hui Zhang ◽  
Yanan Chen ◽  
Huiquan Jiang ◽  
Wenqing Yan ◽  
Yuanming Ouyang ◽  
...  
Keyword(s):  
Knee Joint ◽  
Lower Limb ◽  
Degrees Of Freedom ◽  
Mechanical Axis ◽  
Movement Analysis ◽  
X Rays ◽  
Joint Movement ◽  
X Ray ◽  
Posterior Displacement ◽  
Analysis System

Abstract This study is aimed at obtaining the accuracy of the lower limb mechanical axis (Hip-Knee-Ankle, HKA) by the six degrees of freedom (6DOF) of the knee and ground gait data and analyzing the correlation between the lower limb mechanical axis and 6DOF. We analyzed 3D knee kinematics during ground gait of 99 patients with KOA and 80 patients 6 months after the operations with the vivo infrared navigation 3D portable knee joint movement analysis system (Opti-Knee®, Innomotion Inc, Shanghai, China). Significant correlations with low coefficients (r = -0.19, p = 0.01) between HKA value and anterior-posterior displacement for the whole cohort were found. There were significant correlations with moderate to high coefficients (r = 0.784 to 0.976) between the comparisons of HKA measured on the full-length alignment radiographs and 3D knee joint movement analysis system (Opti-Knee). The further linear correlation analysis showed that there was a significant correlation between the values of HKA measured by X-ray and movement analysis system(R2 = 0.90, p < 0.01). Data with equivalent results as HKA could be provided by knee joint movement analysis system comparing with the conventional X-rays. Nonetheless, there was low significance between the HKA and ground gait data .

scholarly journals Anatomical axis validation of lower extremity for different deformities: A radiological study

2020 ◽  
Vol 8 ◽  
pp. 205031212092382
Author(s):  
Meric Unal ◽  
Sabriye Ercan ◽  
Aydin Budeyri ◽  
Uğur Toprak ◽  
Abdülkerim Şalkaci
Keyword(s):  
Lower Limb ◽  
Mechanical Axis ◽  
Correlation Coefficients ◽  
Strong Positive Correlation ◽  
Knee Alignment ◽  
Intra Class Correlation ◽  
X Ray ◽  
The Past ◽  
Radiology Assistant ◽  
Anatomical Axis

Aim: The aim of this study was to derive a pure, unbiased, reliable and accurate objective relationship between the local knee axis measurements through a short knee anteroposterior roentgenogram and the lower limb axis measurement through an orthoroentgenogram. Patients and Methods: Radiographs of 114 patients (114 knees) were evaluated by two independent raters for measurement of lower limb axis on an orthoroentgenogram and the local knee axis on short knee anteroposterior X-ray, which was derived by cropping the orthoroentgenogram by a blinded radiology assistant. The raters measured at two different time-points separated by an interval of 30-day period. Intra-rater and inter-rater reliabilities were calculated by intra-class correlation coefficients and three models were built to establish the relationships of X-ray anatomical axis with orthoroentgenogram anatomical axis, orthoroentgenogram anatomical axis with orthoroentgenogram mechanical axis and X-ray anatomical axis with orthoroentgenogram mechanical axis. Results: For three different measurements, intra-class correlation coefficients of Rater 2 were higher than 0.90 which shows perfect reliability, while that for Rater 1 was low. Furthermore, first measurements were more consistent than the second measurement. There was a strong positive correlation in all the three models except for varus cases in the last. Conclusion: The standardized correlation derived between the two different techniques for measuring knee alignment is fairly comparable with the studies in the past and would serve as a reliable template for future studies concerning relationships between the two, in addition to helping knee surgeons make more reliable and accurate interpretations through local knee axis measurements.

scholarly journals A Textile Sensor for Long Durations of Human Motion Capture

Sensors ◽  
2019 ◽  
Vol 19 (10) ◽  
pp. 2369 ◽  
Author(s):  
Sufeng Hu ◽  
Miaoding Dai ◽  
Tianyun Dong ◽  
Tao Liu
Keyword(s):  
Knee Joint ◽  
Motion Capture ◽  
Sports Medicine ◽  
Low Cost ◽  
Movement Analysis ◽  
Human Motion ◽  
Joint Movement ◽  
Human Motion Capture ◽  
Knee Joint Motion ◽  
Textile Sensor

Human posture and movement analysis is important in the areas of rehabilitation, sports medicine, and virtual training. However, the development of sensors with good accuracy, low cost, light weight, and suitability for long durations of human motion capture is still an ongoing issue. In this paper, a new flexible textile sensor for knee joint movement measurements was developed by using ordinary fabrics and conductive yarns. An electrogoniometer was adopted as a standard reference to calibrate the proposed sensor and validate its accuracy. The knee movements of different daily activities were performed to evaluate the performance of the sensor. The results show that the proposed sensor could be used to monitor knee joint motion in everyday life with acceptable accuracy.

scholarly journals Analyse Du Rebut Des Cliches Radiographiques Dans Le Service De Radiologie Et Imagerie Médicale Du Chu Campus De Lomé Au Togo

2017 ◽  
Vol 13 (33) ◽  
pp. 244
Author(s):  
P. Gbande ◽  
L. Sonhaye ◽  
K. Adambounou ◽  
K. Lambon ◽  
B. N’timon ◽  
...  
Keyword(s):  
Medical Imaging ◽  
Prospective Study ◽  
Lower Limb ◽  
University Hospital ◽  
X Rays ◽  
Financial Loss ◽  
X Ray ◽  
Chest X Ray ◽  
Almost All

Purpose: To analyze the waste factors of rejected X-rays films. Methodology: Descriptive and analytical prospective study from 1 January to 30 June 2017 carried out in the department of radiology and medical imaging of the Campus University Hospital of Lomé in Togo. Results: 4912 patients had received 5630 radiographic incidences, including 3288 (58.4%) on the analogy and 2342 (41.5%) on the digital. The reject rate was 12.5%. The vast majority of the X-rays films, 682 (96.9%) were rejected by the radiographers themselves just after development. The resumption frequency ranged from one repeat (550 X-rays films, or 78%) to 4 repeats (8 X-rays films, or 1%). Almost all of the rejected films, 702 (99.7%) came from the analogical room. Chest X-ray was the incidence with more rejection in 33.9% followed by pelvic and lower limb incidences in 21% of cases. More than 2/3 of the rejected films, 473 (67.2%), came from the students' act. The causes of the rejection were mainly centering (25.5%), underexposure (20.17%) and overexposure (12.93). The financial loss caused by the scrap of X-rays films amounted to about 418800F CFA or 638.5 €. Conclusion: Strengthening communication between radiographers and radiologists is necessary to avoid unnecessary repeats of patient’s radiographs.

scholarly journals Development of New Analysis Method for Mapping Observations of Clusters of Galaxies

1998 ◽  
Vol 188 ◽  
pp. 312-313
Author(s):  
K. Kikuchi ◽  
T. Ohashi ◽  
H. Ezawa ◽  
M. Hirayama ◽  
H. Honda ◽  
...  
Keyword(s):  
Surface Brightness ◽  
Stray Light ◽  
Physical Parameters ◽  
Clusters Of Galaxies ◽  
X Rays ◽  
X Ray ◽  
Hot Gas ◽  
Cluster Data ◽  
Metal Abundance ◽  
Analysis System

Mapping observations of nearby large-extended clusters of galaxies (Coma, Perseus, Virgo, etc.) are being performed with ASCA. Such clusters allow us to map physical parameters of hot gas in the clusters, such as temperature, metal abundance, and X-ray surface brightness. To determine such parameters at each part of a cluster, one should take careful care of X-ray contamination from outside of a pointed field, which is mainly due to “stray-light” X-rays (Honda et al. 1997). For this reason, the only way to obtain the distribution of hot gas parameter is to process the whole cluster data in a self-consistent way. For this purpose, we are developing the new analysis system called TERRA.

scholarly journals Computed Tomographic Image Analysis Based on FEM Performance Comparison of Segmentation on Knee Joint Reconstruction

2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
Seong-Wook Jang ◽  
Young-Jin Seo ◽  
Yon-Sik Yoo ◽  
Yoon Sang Kim
Keyword(s):  
Image Segmentation ◽  
Knee Joint ◽  
Movement Analysis ◽  
3D Models ◽  
Performance Comparison ◽  
Fe Analysis ◽  
Joint Movement ◽  
Computed Tomographic ◽  
Ct Data ◽  
Scan Data

The demand for an accurate and accessible image segmentation to generate 3D models from CT scan data has been increasing as such models are required in many areas of orthopedics. In this paper, to find the optimal image segmentation to create a 3D model of the knee CT data, we compared and validated segmentation algorithms based on both objective comparisons and finite element (FE) analysis. For comparison purposes, we used 1 model reconstructed in accordance with the instructions of a clinical professional and 3 models reconstructed using image processing algorithms (Sobel operator, Laplacian of Gaussian operator, and Canny edge detection). Comparison was performed by inspecting intermodel morphological deviations with the iterative closest point (ICP) algorithm, and FE analysis was performed to examine the effects of the segmentation algorithm on the results of the knee joint movement analysis.

scholarly journals Ultrafast dynamics of spin and orbital correlations in quantum materials: an energy- and momentum-resolved perspective

2019 ◽  
Vol 377 (2145) ◽  
pp. 20170480 ◽  
Author(s):  
Y. Cao ◽  
D. G. Mazzone ◽  
D. Meyers ◽  
J. P. Hill ◽  
X. Liu ◽  
...  
Keyword(s):  
Degrees Of Freedom ◽  
Two Dimensions ◽  
Great Promise ◽  
X Rays ◽  
Time Resolved ◽  
X Ray ◽  
X Ray Scattering ◽  
Quantum Materials ◽  
Energy And Momentum ◽  
Ray Scattering

Many remarkable properties of quantum materials emerge from states with intricate coupling between the charge, spin and orbital degrees of freedom. Ultrafast photo-excitation of these materials holds great promise for understanding and controlling the properties of these states. Here, we introduce time-resolved resonant inelastic X-ray scattering (tr-RIXS) as a means of measuring the charge, spin and orbital excitations out of equilibrium. These excitations encode the correlations and interactions that determine the detailed properties of the states generated. After outlining the basic principles and instrumentations of tr-RIXS, we review our first observations of transient antiferromagnetic correlations in quasi two dimensions in a photo-excited Mott insulator and present possible future routes of this fast-developing technique. The increasing number of X-ray free electron laser facilities not only enables tackling long-standing fundamental scientific problems, but also promises to unleash novel inelastic X-ray scattering spectroscopies. This article is part of the theme issue ‘Measurement of ultrafast electronic and structural dynamics with X-rays’.

scholarly journals Effects of Total Knee Arthroplasty on Coronal and Sagittal Whole-Body Alignments: Serial Assessments Using Whole-Body EOS

2021 ◽  
Vol 10 (15) ◽  
pp. 3242
Author(s):  
Seong-Chan Kim ◽  
Han-Gyeol Choi ◽  
Joo-Sung Kim ◽  
Tae-Woo Kim ◽  
Yong-Seuk Lee
Keyword(s):  
Knee Joint ◽  
Lower Limb ◽  
Weight Bearing ◽  
Whole Body ◽  
Limb Alignment ◽  
Lower Limb Alignment ◽  
Passive Motion ◽  
X Ray ◽  
Spinopelvic Alignment ◽  
Total Knee

Background: The aims of this study were to evaluate the effects of correcting lower limb alignment by total knee arthroplasty (TKA) on the spinopelvic alignment and to identify patients with difference in the knee joint between clinically measured passive motion and the actual standing posture. Methods: In this retrospective study, 101 patients who underwent TKA and whose serial whole-body EOS X-ray were available were included. The relationship of the knee and spinopelvic alignment was analyzed by evaluating the parameters of standing anterior-posterior and lateral whole-body EOS X-ray. The differences between postoperative passive motion and weight-bearing posture in the knee joint were assessed in both coronal and sagittal planes. Furthermore, the causes of such differences were analyzed. Results: Significant correlations between Δpelvic obliquity and coronal ΔHip-Knee-Ankle (HKA)Rt-Lt angle between the preoperative and 3-month and 1-year postoperative data (p < 0.001 and p < 0.005, respectively) and improved with coronal lower limb alignment close to neutral resulted in decreased pelvic obliquity (p < 0.001, ß = 0.085 and p = 0.005, ß = 0.065, respectively) were observed. The correlations between Δpelvic tilt (PT) and Δsacral slope (SS) and sagittal ΔHKARt-Lt angle were statistically significant (PT: p < 0.001 and p < 0.045; SS: p = 0.002 and p < 0.001, respectively). The improved sagittal alignment close to neutral resulted in decreased PT and increased SS. The difference between postoperative passive motion and the weight-bearing posture of the knee joint was correlated with lumbar lordosis and sagittal C7 plumb line-sacrum distance (p = 0.042 and p < 0.001, respectively). Conclusions: The correction of lower limb alignment with TKA affected pelvic parameters dominantly; however, there was little effect on the spinal alignment. Additionally, patients with anterior stooping or lumbar flat back demonstrated difference in extension between passive knee motion and standing. Therefore, rather than only focusing on changes in the knee alignment correction, knee surgeons should also evaluate the spinopelvic alignment before surgery to consider the prognosis of the standing and predict the possible changes in the whole-body alignment. This preoperative assessment may improve the prognosis of TKA.

An ultrahigh-vacuum goniometer for in situ soft X-ray standing-wave analysis of semiconductor surfaces

1998 ◽  
Vol 5 (3) ◽  
pp. 1029-1031
Author(s):  
Munehiro Sugiyama ◽  
Satoshi Maeyama
Keyword(s):  
Standing Wave ◽  
Photoelectron Spectroscopy ◽  
Ultrahigh Vacuum ◽  
Semiconductor Surfaces ◽  
X Rays ◽  
Edge Structure ◽  
X Ray ◽  
Annealing Effects ◽  
Analysis System

An ultrahigh-vacuum goniometer was developed for in situ X-ray standing-wave (XSW) analysis of semiconductor surfaces prepared by molecular-beam epitaxy (MBE). Although two ultrahigh-vacuum motors for χ and φ rotating axes are inside the analysis chamber, low-energy photoelectrons can still be collected as the magnetic field is sufficiently suppressed by using metal shields. Furthermore, the sample can be annealed at temperatures higher than 870 K on the goniometer in the analysis chamber. This goniometer is used at beamline 1A (BL-1A) at the Photon Factory, where both monochromated soft X-rays and UV radiation are available. This analysis system was shown to be suitable not only for in situ soft-XSW and X-ray absorption near-edge structure (XANES) studies but also for synchrotron radiation photoelectron spectroscopy (SRPES) studies. The annealing effects on an S-adsorbed GaAs(001) surface could be studied by SRPES, XANES and XSW using this new goniometer.

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