scholarly journals 3D simulation of radiographic projections to test and reduce the effect of pelvic tilt on the accuracy of cross-table lateral radiography

2020 ◽  
Vol 21 (1) ◽  
Author(s):  
Jie Xu ◽  
Baohua Su ◽  
Wenhui Zhang ◽  
Hao Sun ◽  
Deng Li ◽  
...  

Abstract Background Cross-table lateral (CL) radiography is a convenient and feasible method to assess cup version angle (VA) after total hip arthroplasty; However, pelvic tilt (PT) may contribute to its measurement inaccuracy. How PT affects CL radiographic measurements have not been well studied. We sought (1) to determine the effect of the PT on cup version measurement on CL radiography and (2) to develop a method for reducing measurement errors caused by the PT. Methods We used 3D technique to construct standard model and capture CL radiography simulation. A linear regression model was created to analyze the relationship between PT and VA. CL radiography and computed tomography (CT) were performed for the enrolled patients after surgery. The consistency between CL and CT measurements were verified by intra-class correlation coefficient (ICC). Results There was a high correlation between the VA and PT. For each 1-degree increased in the PT, the VA decreased by 0.76° (R2 = 0.995, p < 0.001). Based on the data, we created a corrective formula to convert the radiographic measurements into values approximating the actual VA under a natural pelvic position. The VA measurements corrected by our equation was in high agreement with the CT-measured values with reference to the corresponding PT (ICC = 0.988, p < 0.001), which was in sharp contrast to that without PT control (ICC = 0.454, p = 0.203). Conclusions The PT may contribute to cup version measurement inaccuracies on CL radiography. Our mathematical algorithm can serve as a reliable method to improve the accuracy of CL radiography.

2020 ◽  
Author(s):  
Jie Xu ◽  
Baohua Su ◽  
Wenhui Zhang ◽  
Hao Sun ◽  
Deng Li ◽  
...  

Abstract Background: Cross-table lateral (CL) radiography is a convenient and feasible method to assess cup version angle (VA) after total hip arthroplasty; However, pelvic tilt (PT) may contribute to its measurement inaccuracy. How PT affects CL radiographic measurements have not been well studied. We sought (1) to determine the effect of the PT on cup version measurement on CL radiography and (2) to develop a method for reducing measurement errors caused by the PT. Methods: We used 3D technique to construct standard model and capture CL radiography simulation. A linear regression model was created to analyze the relationship between PT and VA. CL radiography and computed tomography (CT) were performed for the enrolled patients after surgery. The consistency between CL and CT measurements were verified by intra-class correlation coefficient (ICC). Results: There was a high correlation between the VA and PT. For each 1-degree increased in the PT, the VA decreased by 0.76° (R²=0.995, p<0.001). Based on the data, we created a corrective formula to convert the radiographic measurements into values approximating the actual VA under a natural pelvic position. The VA measurements corrected by our equation was in high agreement with the CT-measured values with reference to the corresponding PT (ICC=0.988, p<0.001), which was in sharp contrast to that without PT control (ICC=0.454, p=0.203). Conclusions: The PT may contribute to cup version measurement inaccuracies on CL radiography. Our mathematical algorithm can serve as a reliable method to improve the accuracy of CL radiography.


2020 ◽  
Author(s):  
Jie Xu ◽  
Baohua Su ◽  
Wenhui Zhang ◽  
Hao Sun ◽  
Deng Li ◽  
...  

Abstract Background: Cross-table lateral (CL) radiography is a convenient and feasible method to assess cup version angle (VA) after total hip arthroplasty; However, pelvic tilt (PT) may contribute to its measurement inaccuracy. How PT affects CL radiographic measurements have not been well studied. We sought (1) to determine the effect of the PT on cup version measurement on CL radiography and (2) to develop a method for reducing measurement errors caused by the PT. Methods: We used 3D technique to construct standard model and capture CL radiography simulation. A linear regression model was created to analyze the relationship between PT and VA. CL radiography and computed tomography (CT) were performed for the enrolled patients after surgery. The consistency between CL and CT measurements were verified by intra-class correlation coefficient (ICC). Results: There was a high correlation between the VA and PT. For each 1-degree increased in the PT, the VA decreased by 0.76° (R²=0.995, p<0.001). Based on the data, we created a corrective formula to convert the radiographic measurements into values approximating the actual VA under a natural pelvic position. The VA measurements corrected by our equation was in high agreement with the CT-measured values with reference to the corresponding PT (ICC=0.988, p<0.001), which was in sharp contrast to that without PT control (ICC=0.454, p=0.203). Conclusions: The PT may contribute to cup version measurement inaccuracies on CL radiography. Our mathematical algorithm can serve as a reliable method to improve the accuracy of CL radiography.


2020 ◽  
Author(s):  
Jie Xu ◽  
Baohua Su ◽  
Wenhui Zhang ◽  
Hao Sun ◽  
Deng Li ◽  
...  

Abstract Background:Cross-table lateral (CL) radiography is aconvenientandfeasible method toassess cup version angle (VA) after total hip arthroplasty; however, the pelvic tilt (PT) may contribute to its measurement inaccuracy.We sought (1) to determinethe effect of the PT on cup version measurement on CL radiography and (2) to develop a method for reducing measurement errors caused by the PT.Methods: Two groups of VAswere measured respectively on 3D simulatedCL images and CL radiographs. Based on the data, we created a corrective formula to convert the radiographic measurements into values approximating the actual VA under a natural pelvic position. The corrected valueswere compared with computed tomography (CT) measurements to verified the corrective formula. Results:There was a high correlation between the measurements and PTs. For each 1-degree increased in the PT, the VA decreased by 0.76° (R²=0.995, p<0.001). The VA measurements corrected by our equation was in high agreement with the CT-measured valueswithreferenceto the corresponding PT (intra-class correlation coefficient [ICC]=0.988, p<0.001), which was in sharp contrast to that without PT control (ICC=0.454, p=0.203).Conclusions: ThePT may contribute to cup version measurement inaccuracies on CL radiography. Our mathematical algorithm can serve as a reliable method to improve the accuracy of CL radiography.


Author(s):  
Fernanda Aparecida Lopes Magno ◽  
Jairo Hélio Júnior ◽  
Camilo Luis Monteiro Lourenço ◽  
Kariny Rodrigues Pereira ◽  
Joilson Meneguci ◽  
...  

Modern lifestyle is associated with prolonged exposure to sedentary behavior (SB), especially in older adults; however, there is a lack of validated questionnaires to measure SB in Brazilian older adults. The aim of this study was to adapt and validate the Brazilian version of the “Measure of Older Adults Sedentary Time” (MOST) questionnaire in Brazilian older adults. Content validity, clarity and concurrent validity of the adapted MOST were examined. Fifty-seven participants (68.7 ± 3.47 years) answered the adapted version of the MOST questionnaire and wore an ActiGraph wGT3X-BT accelerometer for seven days. After this period, participants answered the adapted MOST again and the accelerometer was collected. MOST answers were summed over for calculating self-reported time spent in SB. A cutoff point of < 100 counts/min was applied to accelerometer data for estimating time spent in SB. The relationship between SB estimates from MOST and accelerometer was verified by Pearson correlation, reproducibility was verified by intra-class correlation coefficient (ICC), internal consistency by Cronbach’s alpha (α) and concordance by Bland Altman. Significance was set at P <0.05. Content validity index and clarity index were 100% and 98%, respectively. ICC was 0.72 (95% CI: 0.56-0.82) for total time in SB assessed with the MOST questionnaire. The correlation between SB estimates from MOST and accelerometer data was 0.37 (95% CI: 0.130.58). The adapted MOST systematically underestimated SB compared to accelerometer (measurement bias: -732.8 min/week [2087.6; -3553.2 min/wk]). The adapted MOST questionnaire presents adequate validity for assessing SB in the Brazilian older adults.


2021 ◽  
Vol 15 (11) ◽  
pp. 3365-3367
Author(s):  
Mazhar Ali Bhutto ◽  
Azadeh Shadmehr ◽  
M. Raza Hadian ◽  
Saeed Talebian ◽  
Zeb Jehan Rana ◽  
...  

Aim: Capturing body images through digital photography method for calculation of quadriceps angles and pelvic position in clinical assessment is an inexpensive method. The aim of this study is to evaluate the reliability of measuring Q-angle and pelvic tilt angle with digital camera and Microdicom software. Place and duration: University of Lahore and Tehran University of medical sciences, from June 2020 to June 2021 Methods: Bilateral lower limbs of fifteen healthy asymptomatic subjects were considered for calculations of desired angles. A 13-megapixel camera was used to capture images of quadriceps angle (q-angle) measurement in an anterior view and for pelvic angle measurement image in lateral view along with specific landmark markers on the body were captured. Images were transferred to Microdicom software for calculating desire angles. Three trails of procedures and Intra-class Correlation Coefficient (ICC) with 95% Confidence Interval (CI), Munro’s classification for reliability coefficients were used for the description of degrees. Standard error of measurement (SEM) was also calculated. Results: The Intra-class correlation coefficient values for right side Q- angle was 0.949(0.878-.981) and for left side it was 0.924(0.819-0.972) and <0.005 significant p-value. The ICC results for measuring pelvic title angle in the right side .990 (.975-.996) and left legs were .991 (.974-.997). Showing that the results were highly reliable and significant (p<0.005). Conclusions: The q-angle and pelvic angle measured with digital image have excellent consistency and reliability. Keywords: angle, asymptomatic, Images, pelvic, quadriceps


2017 ◽  
Vol 17 (10) ◽  
pp. S200
Author(s):  
Ann M. Hayes ◽  
Howard M. Place ◽  
Andy Hayden ◽  
Jennifer L. Brechbuhler

2021 ◽  
pp. 003151252110365
Author(s):  
Alessandra V. Prieto ◽  
Kênnea Martins Almeida Ayupe ◽  
Ana C. A. Abreu ◽  
Paulo J. B. Gutierres Filho

Improvement in rider mobility represents an important functional gain for people with disabilities undergoing hippotherapy. However, there is no validated measuring instrument to track and document the rider's progress in riding activities. In this study, we aimed to develop and establish validity evidence for an instrument to assess hippotherapy participants’ mobility on horseback. We report on this development through the stages of: (a) content validation, (b) construct validation, (c) inter- and intra-rater reliability and (d) internal consistency analysis. We evaluated its factor structure with exploratory factor analyses, calculated values for inter- and intra-rater reliability using the intra-class correlation coefficient, and calculated its internal consistency using Cronbach's alpha. We followed recommendations by the Guidelines for Reporting Reliability and Agreement Studies. We found good inter-rater reliability (intra-class correlation coefficient – ICC = 0.991–0.999) and good intra-rater reliability (ICC = 0.997–1.0), and there was excellent internal consistency (Cronbach's α = 0.937–0.999). The instrument’s factor structure grouped its three domains into one factor. As this instrument is theoretically consistent and has been found to be appropriate and reliable for its intended use, it is now available for the measurement of horseback mobility among hippotherapy riders.


2013 ◽  
Vol 25 (1) ◽  
pp. 65-68 ◽  
Author(s):  
Hee Sung Lim ◽  
Su Yeon Roh ◽  
Suk Min Lee

Author(s):  
Yusuf O. Akinwale

Background: This article contributes to existing literature by examining the relationship between inbound open innovation and firms’ financial performance in the Nigerian oil and gas industry. Aim: This article seeks to identify the factors of inbound open innovation and whether these factors influence the financial performance of small and medium-sized enterprises (SMEs) in the Nigerian oil and gas industry. Setting: This article examines 150 indigenous oil and gas SMEs in the upstream subsector of the Nigerian petroleum sector through a survey, using a questionnaire, conducted in 2015. Methods: The study applied the structural equation modelling (SEM) method. This method is used to test the relationships between the factors and to calculate the measurement errors in the hypotheses formulated. Results: The results show that technology scouting, vertical technology collaboration (VTC) and horizontal technology collaboration (HTC) positively and significantly contribute to inbound open innovation, which are thus significant in influencing the financial performance of SMEs. The size of technical staff and research and development (R&D) fund allocations also have a positive and significant correlation with the SMEs’ financial performance. Meanwhile, the age of SMEs is negative and not significant in influencing financial performance. Conclusion: The results suggest that inbound open innovation through scouting, HTC and VTC should therefore be encouraged among SMEs to boost their internal capabilities, which have hitherto enhanced their financial performance. The management members of each SME should continually consider collaboration with the external actors because they cannot singularly possess all the innovative skills required in the industry. Also, each firm should commit itself to allocate more funds to R&D and at the same time should hire those who have relevant production skills and train the existing ones in their firms.


Hand Surgery ◽  
2010 ◽  
Vol 15 (02) ◽  
pp. 71-73 ◽  
Author(s):  
Rouin Amirfeyz ◽  
Sanchit Mehendale ◽  
Sarah Tyrrell ◽  
Raj Bhatia ◽  
Ian Leslie ◽  
...  

Katz and Stirrat devised a hand diagram, which uses subjective information from the patient for the diagnosis of carpal tunnel syndrome (CTS). They reported a good result. We tested the inter-observer and intra-observer reliability of this hand diagram. Twenty five consecutive patients with a diagnosis of CTS, 25 with other common hand and wrist problems but CTS and 25 healthy individuals were prospectively recruited. Each patient filled in a hand diagram. Two experienced hand surgeon scored the diagrams blindly on two different sittings four-week apart. The intra-class correlation coefficient (ICC) and Cohen's Kappa were used for intra and inter-observer reliability respectively. The intra-observer agreement was poor (ICC 95% 0.33–0.65) and inter-observer was fair (Kappa = 0.241). This study does not support the use of Katz and Stirrat Hand Diagram for the diagnosis of carpal tunnel syndrome in place if a thorough clinical examination.


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