Automatic CT segmentation of proximal femur has a great potential for use in orthopedic diseases, especially in the imaging-based assessments of hip fracture risk. In this study, we proposed an ...approach based on deep learning for the fast and automatic extraction of the periosteal and endosteal contours of proximal femur in order to differentiate cortical and trabecular bone compartments. A three-dimensional (3D) end-to-end fully convolutional neural network (CNN), which can better combine the information among neighbor slices and get more accurate segmentation results by 3D CNN, was developed for our segmentation task. The separation of cortical and trabecular bones derived from the QCT software MIAF-Femur was used as the segmentation reference. Two models with the same network structures were trained, and they achieved a dice similarity coefficient (DSC) of 97.82% and 96.53% for the periosteal and endosteal contours, respectively. Compared with MIAF-Femur, it takes half an hour to segment a case, and our CNN model takes a few minutes. To verify the excellent performance of our model for proximal femoral segmentation, we measured the volumes of different parts of the proximal femur and compared it with the ground truth, and the relative errors of femur volume between predicted result and ground truth are all less than 5%. This approach will be expected helpful to measure the bone mineral densities of cortical and trabecular bones, and to evaluate the bone strength based on FEA.
Graphical abstract
The aim of the study was to investigate the 3.0 Tesla magnetic resonance imaging (MRI) features of Madelung's deformity.
The wrist MRI scans of 19 patients clinically diagnosed with Madelung's ...deformity and 20 patients without deformity were consecutively selected from Beijing Jishuitan Hospital between April 2019 and December 2022 for observation, in the case group and control group, respectively. Multiple linear regression was used to analyze the factors affecting tilting angle and width of central disc (CD, also termed as triangular fibrocartilage, the main component of triangular fibrocartilage complex), while the chi-square test was used to compare the occurrences of CD (radial) attachment displacement, VL, and RTL. p < 0.05 indicated statistical significance.
Madelung's deformity significantly contributed to the tilting and thickening of the CD. In the case group, the tilting angle and thickness of CD were (51.46 ± 1.33)° and (0.23 ± 0.01) cm, respectively, which was statistically significant (p < 0.05); the radial attachment of the CD significantly shifted away from the distal articular surface level (χ
= 39.00, p < 0.001), with a mean displacement of (0.97 ± 0.38) cm. Furthermore, the cases demonstrated abnormally developed Vickers ligament (χ
= 35.19, p < 0.001) and radiotriquetral ligament (χ
= 25.66, p < 0.001).
MRI provides a notable advantage in diagnosing Madelung's deformity. Compared with the control group, patients with Madelung's deformity exhibited tilting and thickening of the CD. Additionally, the radial attachment of the CD was significantly shifted proximally with abnormal development of Vickers and radiotriquetral ligaments.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Asynchronous calibration quantitative computed tomography (QCT) is a new tool that allows the quantification of bone mineral density (BMD) without the use of a calibration phantom during scanning; ...however, this tool is not fully validated for clinical use. We used the European spine phantom (ESP) with repositioning during scanning and assessed the accuracy and short-term reproducibility of asynchronous QCT. Intra-scanner and intra-observer precision were each calculated as the root mean square of the standard deviation (RMSSD) and the coefficient of variation (CV-RMSSD). We also compared asynchronous and conventional QCT results in 50 clinical subjects. The accuracy of asynchronous QCT for three ESP vertebrae ranged from 1.4-6.7%, whereas intra-scanner precision for these vertebrae ranged from 0.53-0.91 mg/cc. Asynchronous QCT was most precise for a trabecular BMD of 100 mg/cc (CV-RMSSD = 0.2%). For intra-observer variability, overall precision error was smaller than 3%. In clinical subjects there was excellent agreement between the two calibration methods with correlation coefficients ranging from 0.96-0.99. A Bland-Altman analysis demonstrated that methodological differences depended on the magnitude of the BMD variable. Our findings indicate that the asynchronous QCT has good accuracy and precision for assessing trabecular BMD in the spine.
Skeletal muscle density, measured by computed tomography (CT) as the mean attenuation in Hounsfield Units (HU) (also termed myosteatosis), is well established as a biomarker for predicting mortality ...and treatment-related outcomes in cancers, 1 heart failure, 2 frailty fractures and other diseases. 3–5 We therefore read with interest the paper ‘Subcutaneous fat area at the upper thigh level is a useful prognostic marker in the elderly with femur fracture’ by Kim et al. 6 The authors presented an interesting study on the impact of body tissue composition at the upper thigh level on 1-year mortality in elderly patients with a proximal femur fracture. The authors highlight the importance of the upper thigh subcutaneous fat area as an independent prognostic marker for elderly hip fracture patients that could be highly useful for planning personalized nutritional support and rehabilitation interventions to reduce mortality. Adjusted* hazard ratios of death risk per one SD decrease of G.MaxM area (A), G. MaxM density (B), G.Med/MinM area (C) and G.Med/MinM density (D) with time frame. *Adjusted for age, sex and Parker score before hip fracture.
In order to facilitate engineers to manage dynamic loads in real time and improve the utilization of power cables, it is necessary to accurately calculate the temperature rise of cable cores under ...duct laying conditions. The transient thermal circuit model involved in this paper helps to improve the speed of dynamic response and the accuracy of transient temperature rise calculation for power cable cores under duct laying conditions. Since the impact of the environmental conditions, exploring the computational relationships of the thermal circuit model parameters helps to improve the engineering applicability of the model. The duct cable can be broken down into three parts: the cable body, the air inside the pipe and the external environment. In engineering, the thermal circuit model parameters of the cable body can be made into a table and applied by looking up the table. The thermal circuit model parameters of air in duct are related to the cable outside diameter and duct inside diameter, and can also be engineered using tables for application. The fit gives the third part of the equation with respect to the thermal resistance coefficient of the duct and soil and the burial depth. The error in applying the decentralized thermal circuit model and parametric expressions is less than 1 °C compared to the results of finite element calculations. This proves that the decomposition of the duct power cable model improves the accuracy of the transient temperature rise calculation. The relationship equation between the parameters of the thermal circuit model and the laying conditions helps to improve the engineering adaptability of the method.
Previous studies have reported conflicting results for the relationships between anthropometric adiposity indexes and bone mineral density, based on dual-energy X-ray absorptiometry (DXA). However, ...few studies were published based on quantitative computed tomography (QCT), especially for Chinese population.
To evaluate the associations of spine bone mineral density (BMD) with body mass index (BMI), waist circumstance (WC), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR) and a body shape index (ABSI) using QCT.
A Cross-sectional study.
Around 3,457 participants in multiple communities across 7 administrative regions of China.
Spine BMD was measured using QCT, and the classification of osteoporosis was defined as follows: 1) osteoporosis if BMD <80mg/cm3, 2) osteopenia if BMD 80–119 mg/cm3, and 3) normal bone mass if BMD≥120 mg/cm3.
This study was conducted using convenient sampling between 2013 and 2017. Multivariable linear regression model and logistic regression models were used for the associations of continuous and categorical BMD, respectively.
Around 3,405 participants were included in the final analyses, including 1,272 males and 2,133 females, with spine BMD of 111.00±35.47 mg/cm3 and 99.38±40.60 mg/cm3, respectively. Spine BMD decreased significantly with the increase of ABSI in females (adjusted β, −5.74; 95% confidence interval CI, −8.50 to −2.98), and this trend also was kept in females aged at less than 60 years (adjusted β, −14.54; 95% CI, −20.40 to −8.68), and females with age ≥60 years (adjusted β, −7.59; 95% CI, −10.91 to −4.28). However, this inverse association was observed only in males with age ≥ 60 years (adjusted β, −5.19; 95% CI, −10.08 to −0.29). Except ABSI, negative associations of Spine BMD with WC (adjusted β, −0.46; 95% CI, −0.77 to −0.15), WHR (adjusted β, −6.25; 95% CI, −10.63 to −1.86), WHtR (adjusted β, −6.80; 95% CI, −11.63 to −1.97) were shown in females aged at <60 years, and positive association with BMI in males with age ≥60 years (adjusted β, 0.92; 95% CI, 0.29–1.55).
ABSI had more remarkable association with spine BMD, compared with the other four indexes.
Lumbar vertebral endplates lesions (LEPLs), one of the etiologies of low back pain (LBP), are one of the most prevalent causes of health-care costs. Despite progressively becoming the focus in recent ...years, almost all studies have concentrated on symptomatic patients rather than general populations. As a result, our study was designed to determine the prevalence and distribution patterns of LEPLs in a middle-young general population, as well as their associations with lumbar disc herniation (LDH), lumbar disc degeneration (LDD), and lumbar vertebral volumetric bone mineral density (vBMD).
Seven hundred fifty-four participants aged 20-60 years were recruited from the subjects enrolled in a 10-year longitudinal study of degeneration of the spine and knee being conducted at the Beijing Jishuitan Hospital and 4 of them were excluded due to the missing of MRIs. In this observational study, a lumbar quantitative computed tomography (QCT) and MRI scan were performed among participants within 48 h. T2-weighted sagittal lumbar MRI images for all included subjects were identified for LEPLs by two independent observers based on morphological and local characteristics. Lumbar vertebral vBMD was measured with QCT. The age, BMI, waistline, hipline, lumbar vBMD, LDD, and LDH were measured to investigate their associations with LEPLs.
The prevalence of LEPLs was higher among the male subjects. 80% of endplates were recognition as no lesions with a substantial disparity between female (75.6%) and male subjects (83.4%) (p < 0.001). The most common lesions were "wavy/irregular" and "notched", and "fracture" is most involved in L3-4 inferior endplate both in two genders. LEPLs were found to be associated with LDH (≥ 2 levels: OR = 6.859, P < 0.001; 1 level: OR = 2.328, P = 0.002 in men. OR = 5.004, P < 0.001; OR = 1.805, P = 0.014 in women) reference for non-LDH, and hipline in men (OR = 1.123, P < 0.001).
LEPLs are the common findings on lumbar MRIs in general population, particularly in men. The presence of these lesions and advance from slightly to severely could be mainly attributed to LDH and men's higher hipline.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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