Fracture Discrimination Research Articles

Study on Fracture Evolution and Water-Conducting Fracture Zone Height beneath the Sandstone Fissure Confined Aquifer

Studying the evolution law of overlying rock fissures and predicting the development height of water-conducting fissure zones is the key to preventing roof water damage, protecting mine water resources, and realizing the safe and sustainable development of the mine. To study the overburden fracture evolution law of coal mining under aquifer conditions, the 1402 working face of Longwangzhuang Mine in Shaanmian Coalfield serves as the engineering background based on the Fractal Theory and similar simulation technology; this paper analyzes the fracture evolution of overburden rock and the development law of Water-Conducting Fracture Zone (WCFZ) during the advancing of working face, and further puts forward a model for the location discrimination of overburden fracture based on plate theory. The results indicate that post-mining, overburden rock failure assumes a trapezoidal shape, and fractures around the cutting hole and the side of the working face fully develop, while those in the middle of the goaf tend to compact. The distribution of the fracture network of mining strata at different advancing distances has good self-similarity, and the fractal dimension of the fracture network of overlying rock can be divided into three stages: ascending dimension, decreasing dimension, and stable phase. The II 1 coal seam fracture does not spread to the Sandstone Fissure Confined Aquifer. These findings provide strategic guidance for protecting mine aquifer water resources, preventing and controlling roof water inrush, and ensuring safe and sustainable production within the study area.

Hip Fracture Risk Assessment Tools for Adults Aged 80 Years and Older

While adults aged 80 years and older account for 70% of hip fractures in the US, performance of fracture risk assessment tools in this population is uncertain. To compare performance of the Fracture Risk Assessment Tool (FRAX), Garvan Fracture Risk Calculator, and femoral neck bone mineral density (FNBMD) alone in 5-year hip fracture prediction. Prognostic analysis of 3 prospective cohort studies including participants attending an index examination (1997 to 2016) at age 80 years or older. Data were analyzed from March 2023 to April 2024. Participants contacted every 4 or 6 months after index examination to ascertain incident hip fractures and vital status. Predicted 5-year hip fracture probabilities calculated using FRAX and Garvan models incorporating FNBMD and FNBMD alone. Model discrimination assessed by area under receiver operating characteristic curve (AUC). Model calibration assessed by comparing observed vs predicted hip fracture probabilities within predicted risk quintiles. A total of 8890 participants were included, with a mean (SD) age at index examination of 82.6 (2.7) years; 4906 participants (55.2%) were women, 866 (9.7%) were Black, 7836 (88.1%) were White, and 188 (2.1%) were other races and ethnicities. During 5-year follow-up, 321 women (6.5%) and 123 men (3.1%) experienced a hip fracture; 818 women (16.7%) and 921 men (23.1%) died before hip fracture. Among women, AUC was 0.69 (95% CI, 0.67-0.72) for FRAX, 0.69 (95% CI, 0.66-0.72) for Garvan, and 0.72 (95% CI, 0.69-0.75) for FNBMD alone (FNBMD superior to FRAX, P = .01; and Garvan, P = .01). Among men, AUC was 0.71 (95% CI, 0.66-0.75) for FRAX, 0.76 (95% CI, 0.72-0.81) for Garvan, and 0.77 (95% CI, 0.72-0.81) for FNBMD alone (P < .001 Garvan and FNBMD alone superior to FRAX). Among both sexes, Garvan greatly overestimated hip fracture risk among individuals in upper quintiles of predicted risk, while FRAX modestly underestimated risk among those in intermediate quintiles of predicted risk. In this prognostic study of adults aged 80 years and older, FRAX and Garvan tools incorporating FNBMD compared with FNBMD alone did not improve 5-year hip fracture discrimination. FRAX modestly underpredicted observed hip fracture probability in intermediate-risk individuals. Garvan markedly overpredicted observed hip fracture probability in high-risk individuals. Until better prediction tools are available, clinicians should prioritize consideration of hip BMD, life expectancy, and patient preferences in decision-making regarding drug treatment initiation for hip fracture prevention in late-life adults.

A plasma protein-based risk score to predict hip fractures

As there are effective treatments to reduce hip fractures, identification of patients at high risk of hip fracture is important to inform efficient intervention strategies. To obtain a new tool for hip fracture prediction, we developed a protein-based risk score in the Cardiovascular Health Study using an aptamer-based proteomic platform. The proteomic risk score predicted incident hip fractures and improved hip fracture discrimination in two Trøndelag Health Study validation cohorts using the same aptamer-based platform. When transferred to an antibody-based proteomic platform in a UK Biobank validation cohort, the proteomic risk score was strongly associated with hip fractures (hazard ratio per s.d. increase, 1.64; 95% confidence interval 1.53–1.77). The proteomic risk score, but not available polygenic risk scores for fractures or bone mineral density, improved the C-index beyond the fracture risk assessment tool (FRAX), which integrates information from clinical risk factors (C-index, FRAX 0.735 versus FRAX + proteomic risk score 0.776). The developed proteomic risk score constitutes a new tool for stratifying patients according to hip fracture risk; however, its improvement in hip fracture discrimination is modest and its clinical utility beyond FRAX with information on femoral neck bone mineral density remains to be determined.

Response characteristics of acoustic emission signal and judgment criteria for different fracture modes

Coal mining is going deeper into the ground, resulting in more intense and frequent mine dynamic disasters. To ensure the early warning of dynamic disasters, it is significant to accurately reveal the differences of acoustic emission (AE) signals generated by rock fractures. This paper focuses on studying how AEs average frequency (AF) and rise angle (RA) change in sandstone during loading, and examines the characteristics of waveform amplitude, energy, and frequency distribution of AE signals from different types of fractures. The findings reveal that the percentage of shear fracture gradually increases with increasing load, and the energy activity of the AE signal is significantly enhanced in the high stress stage. The occurrence of the main fracture was preceded by a large number of low-frequency tensile fracture AE signals, accompanied by a small decrease in RA and a small increase in AF. The spectra of different fracture signals were characterized as “low anomalous F” for shear fractures, “vertical F” for low-frequency tensile fractures, and “high anomalous F” for high-frequency tensile fractures. Their energy distribution in the frequency domain was respectively described as “peak-centered distribution”, “pillar-shaped distribution” and “peak-skewed distribution”. The outcomes of the decomposition and reconstruction from the P- and S-waves reveal that the P wave energy (Ep) dominates in the high-frequency tensile fracture AE signal, while the S wave energy (Es) is greater in the low-frequency tensile fracture and the shear fracture AE signals. The ES/EP threshold value for laboratory discrimination of tensile and shear fracture is 3, as the fracture extends and penetrates, the ES/EP value rises rapidly at the appearance of macroscopic fracture. The findings offer theoretical guidance for monitoring and early warning of coal and rock dynamic hazards as well as revealing the morphology of fracture source.

Fracture discrimination capability of ulnar flexural rigidity measured via Cortical Bone Mechanics Technology: study protocol for The STRONGER Study.

Osteoporosis is characterized by low bone mass and structural deterioration of bone tissue, which leads to bone fragility (ie, weakness) and an increased risk for fracture. The current standard for assessing bone health and diagnosing osteoporosis is DXA, which quantifies areal BMD, typically at the hip and spine. However, DXA-derived BMD assesses only one component of bone health and is notably limited in evaluating the bone strength, a critical factor in fracture resistance. Although multifrequency vibration analysis can quickly and painlessly assay bone strength, there has been limited success in advancing a device of this nature. Recent progress has resulted in the development of Cortical Bone Mechanics Technology (CBMT), which conducts a dynamic 3-point bending test to assess the flexural rigidity (EI) of ulnar cortical bone. Data indicate that ulnar EI accurately estimates ulnar whole bone strength and provides unique and independent information about cortical bone compared to DXA-derived BMD. Consequently, CBMT has the potential to address a critical unmet need: Better identification of patients with diminished bone strength who are at high risk of experiencing a fragility fracture. However, the clinical utility of CBMT-derived EI has not yet been demonstrated. We have designed a clinical study to assess the accuracy of CBMT-derived ulnar EI in discriminating post-menopausal women who have suffered a fragility fracture from those who have not. These data will be compared to DXA-derived peripheral and central measures of BMD obtained from the same subjects. In this article, we describe the study protocol for this multi-center fracture discrimination study (The STRONGER Study).

Increased circulating microRNA-21 level as a potential indicator for predicting a higher risk of incident fragility fractures.

As a common disease in the elderly, osteoporosis clearly increases the risk of fractures, leading to higher mortality, but the current markers to estimate the risk of fractures are limited. MicroRNA-21 (miR-21) may play an important role in osteoporosis, but the link of this biomarker with fractures was undetermined. We aimed to investigate the association between miR-21 levels and the presence of fragility fractures. A total of 200 patients were recruited and miR-21 was collected from baseline serum. The correlation between miR-21 and the fracture risk assessment tool (FRAX) score was analyzed. The incidence of fragility fractures was presented by Kaplan-Meier analysis, and Cox regression analysis was utilized to evaluate risk factors. The diagnostic value of miR-21 was conducted by the area under curve (AUC). The FRAX score was significantly associated with miR-21 level (p<0.001). According to the 50th percentile of miR-21 content in the overall distribution, the cumulative incidence of fragility fractures was significantly higher in patients with higher miR-21 levels than those with lower levels (75.4, 95 % CI: 69.0-81.8 vs. 59.2, 95 % CI: 42.1-76.3, p<0.001). The results of the Cox regression analysis showed that the miR-21 level was an independent risk factor linked to the incidence of fracture (p=0.005). The optimal cut-off value of the miR-21 was 6.08, and the AUC for predicting fracture was 0.718 (95 % CI, 0.645-0.790). This study showed that miR-21 has optimal diagnostic performance in the discrimination of fragility fracture, and the circulating miR-21 level in predicting the risk of fragility fracture may have a certain value.

PREDICTION OF FRAGILE FRACTURE USING DEEP LEARNING BASED ON ULTRASOUND RADIOFREQUENCY SIGNAL: A PILOT STUDY

Quantitative ultrasound (QUS) is a promising tool to estimate bone structure characteristics and predict fragile fracture. The aim of this pilot cross-sectional study was to evaluate the performance of a multi-channel residual network (MResNet) based on ultrasonic radiofrequency (RF) signal to discriminate fragile fractures retrospectively in postmenopausal women.MethodsRF signal and speed of sound (SOS) were obtained using an axial transmission QUS at one‐third distal radius for 246 postmenopausal women. Based on the involved RF signal, we conducted a MResNet, which combines multi-channel training with original ResNet, to classify the high risk of fragility fractures patients from all subjects. The bone mineral density (BMD) at lumber, hip and femoral neck acquired with DXA was recorded on the same day. The fracture history of all subjects in adulthood were collected. To assess the ability of the different methods in the discrimination of fragile fracture, the odds ratios (OR) calculated using binomial logistic regression analysis and the area under the receiver operator characteristic curves (AUC) were analyzed.ResultsAmong the 246 postmenopausal women, 170 belonged to the non-fracture group, 50 to the vertebral group, and 26 to the non-vertebral fracture group. MResNet was discriminant for all fragile fractures (OR = 2.64; AUC = 0.74), for Vertebral fracture (OR = 3.02; AUC = 0.77), for non-vertebral fracture (OR = 2.01; AUC = 0.69). MResNet showed comparable performance to that of BMD of hip and lumbar with all types of fractures, and significantly better performance than SOS all types of fractures.Conclusionsthe MResNet model based on the ultrasonic RF signal can significantly improve the ability of QUS device to recognize previous fragile fractures. Moreover, the performance of the proposed model modified by age, weight, and height is further optimized. These results open perspectives to evaluate the risk of fragile fracture applying a deep learning model to analyze ultrasonic RF signal.

Machine learning applied to HR-pQCT images improves fracture discrimination provided by DXA and clinical risk factors.

Traditional analysis of High Resolution peripheral Quantitative Computed Tomography (HR-pQCT) images results in a multitude of cortical and trabecular parameters which would be potentially cumbersome to interpret for clinicians compared to user-friendly tools utilising clinical parameters. A computer vision approach (by which the entire scan is 'read' by a computer algorithm) to ascertain fracture risk, would be far simpler. We therefore investigated whether a computer vision and machine learning technique could improve upon selected clinical parameters in assessing fracture risk. Participants of the Hertfordshire Cohort Study (HCS) attended research visits at which height and weight were measured; fracture history was determined via self-report and vertebral fracture assessment. Bone microarchitecture was assessed via HR-pQCT scans of the non-dominant distal tibia (Scanco XtremeCT), and bone mineral density measurement and lateral vertebral assessment were performed using dual-energy X-ray absorptiometry (DXA) (Lunar Prodigy Advanced). Images were cropped, pre-processed and texture analysis was performed using a three-dimensional local binary pattern method. These image data, together with age, sex, height, weight, BMI, dietary calcium and femoral neck BMD, were used in a random-forest classification algorithm. Receiver operating characteristic (ROC) analysis was used to compare fracture risk identification methods. Overall, 180 males and 165 females were included in this study with a mean age of approximately 76years and 97 (28%) participants had sustained a previous fracture. Using clinical risk factors alone resulted in an area under the curve (AUC) of 0.70 (95% CI: 0.56-0.84), which improved to 0.71 (0.57-0.85) with the addition of DXA-measured BMD. The addition of HR-pQCT image data to the machine learning classifier with clinical risk factors and DXA-measured BMD as inputs led to an improved AUC of 0.90 (0.83-0.96) with a sensitivity of 0.83 and specificity of 0.74. These results suggest that using a three-dimensional computer vision method to HR-pQCT scanning may enhance the identification of those at risk of fracture beyond that afforded by clinical risk factors and DXA-measured BMD. This approach has the potential to make the information offered by HR-pQCT more accessible (and therefore) applicable to healthcare professionals in the clinic if the technology becomes more widely available.

Clinical Utility of Thigh and Mid-Thigh Dual-Energy x-Ray Absorptiometry to Identify Bone and Muscle Loss.

Sarcopenia and osteoporosis are highly prevalent syndromes in older people, characterized by loss of muscle and bone tissue, and related to adverse outcomes. Previous reports indicate mid-thigh dual-energy X-ray absorptiometry (DXA) is well suited for the simultaneous assessment of bone, muscle, and fat mass in a single scan. Using cross-sectional clinical data and whole-body DXA images of 1322 community-dwelling adults from the Geelong Osteoporosis Study (57% women, median age 59 years), bone and lean mass were quantified in three unconventional regions of interest (ROIs): (i) a 2.6-cm-thick slice of mid-thigh, (ii) a 13-cm-thick slice of mid-thigh, and (iii) the whole thigh. Conventional indices of tissue mass were also calculated (appendicular lean mass [ALM] and bone mineral density [BMD] of lumbar spine, hip, and femoral neck). The performance of thigh ROIs in identifying osteoporosis, osteopenia, low lean mass and strength, past falls, and fractures was evaluated. All thigh regions (especially whole thigh) performed well in identifying osteoporosis (area under the receiver-operating characteristic [ROC] curve [AUC] > 0.8) and low lean mass (AUC >0.95), but they performed worse in the diagnosis of osteopenia (AUC 0.7-0.8). All thigh regions were equivalent to ALM in discrimination of poor handgrip strength, gait speed, past falls, and fractures. BMD in conventional regions was more strongly associated with past fractures than thigh ROIs. In addition to being faster and easier to quantify, mid-thigh tissue masses can be used for identifying osteoporosis and low lean mass. They are also equivalent to conventional ROIs in their associations with muscle performance, past falls, and fractures; however, further validation is required for the prediction of fractures. © 2022 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

The evolution characteristics of rock fracture instability under cyclic loading on the basis of the enhanced LURR

Prospective discrimination of rock instability and fracture is a key problem in mining, slope stability, earthquake triggering, and other research fields. Through the rock fracture experiment, scientists put forward the load unload response ratio (referred to as LURR) to detect the non-linear deformation process of the strain stress curve, judge the degree of rock damage and instability fracture, which is accepted worldwide and has been widely used in seismic risk assessment. But, the extraction of response parameters (including strain, energy, well water level, etc.) are faced with many difficulties in actual observation, which makes the application of results uncertain. In this paper, the change of relative wave velocity is proposed as the loading unloading response parameter. Through rock mechanics experiments, a prospective discrimination method of rock instability and fracture process is constructed. The change characteristics of the LURR in the process of rock instability and fracture under stress are studied, the experiment result show that: when approaching the main fracture, the LURR calculated by taking the transverse strain energy as the response quantity obviously rises and fall back, the acoustic emission energy release rate and event rate are close to exponential acceleration process; The LURR by taking the change of relative wave velocity as the response parameter, first decreases, then fluctuates near zero, and rapidly decreases to below zero when it reaches the critical failure. The change combination of the above parameters’ response ratio can effectively judge the process of rock deformation, instability and fracture under stress. Moreover, this study of the load unload response ratio which takes the change of relative wave velocity as the response parameter, makes up the deficiency of the traditional load unload response ratio method in judging the rock instability of the medium under stress.

MO546: Association Between T Scores, FRAX, Frailty, Falls and Fractures in Patients Undergoing Maintenance Hemodialysis

Abstract BACKGROUND AND AIMS Despite the negative impact of fracture in hemodialysis (HD) patients, optimal risk assessment tools in this population are not well explored. Frailty (a syndrome of diminished capacity to respond to health stressors) and falls—known risk factors for fracture—are common in HD patients. While the relationship between T scores in relation to fractures in these patients is recognized, there is a paucity of data to the additional contributions of fracture risk assessment tool (FRAX), frailty and falls in relation to fractures. The clinical, societal and economic impact of fractures necessitates an active response from the HD programs. Therefore, we intended to evaluate the clinical utility of adding these factors to T scores at the femoral neck to determine whether it enhances fracture discrimination in HD patients. METHOD We conducted a cross-sectional study on 131 adult patients receiving HD at two dialysis units in Regina, Saskatchewan, Canada (January 2017–December 2018). After undergoing frailty assessments, patients were referred for dual-energy X-ray absorptiometry (DXA) scans and FRAX questionnaires. They were additionally sent for lumbar X-rays and contacted for a history of falls. The presence of fracture (hips, femur, pelvis, knee, foot, leg, toe, shoulder, elbow, ankle, arm, wrist, spine and lumbar) was documented based on the review of medical charts, self-recall and additionally vertebral fractures were identified by an X-ray. Bone mineral density (BMD) was measured by DXA. FRAX score (the 10-year probability of hip and major osteoporotic fracture) was calculated using an online algorithm based on 11 clinical risk factors with and without the inclusion of BMD. Frailty was assessed using the FRIED criteria (Figure 1). Patients were enquired about the history and frequency of falls. Association between the BMD-T score, FRAX score, frailty status, falls, with fracture were examined with sequential multivariable logistic regression models. The area under the receiver operating characteristic curve analysis was conducted for each model to assess its discrimination ability for fracture outcome (α = 0.05). RESULTS A total of 109 HD patients were included in the data analysis. The composite of fracture occurred in 38% of patients. About 60% were identified as frail, and 29% had at least one fall in the last year. Low T score and FRAX were both independent risk factors in patients on HD therapy. On multivariate analysis, each lower standard deviation in T score was associated with 48% higher odds of fracture [odds ratio (OR) = 1.48; 95% confidence interval (95% CI) 1.20–1.68, P = 0.005]. With the inclusion of FRAX score for hip fracture, the OR for fracture remained significant at 1.38 (OR = 1.38, 95% CI 1.04–1.63, P = 0.04). The addition of frailty status and history of falls did not further improve the model. Model 2 showed better discrimination ability and goodness-of-fit for fracture compared to Model 1 (P = 0.004) (Table). CONCLUSION This is the first study to our knowledge that looked at the independent contribution of frailty and falls in addition to T scores and FRAX in assessing for fractures in patients on HD. Our study showed both BMD measurements by DXA scans and FRAX are useful tools to assess fracture in patients receiving HD. The addition of frailty status and history of falls is not associated with fractures in this population. Results of this study should lead to prospective studies with larger sample sizes prior to DXA scans, FRAX and falls assessment being recommended as standards of care.

Bone Texture Assessment on Lateral VFAs Using the Texture Research Investigational Platform (TRIP) and its Fracture Discrimination Ability

Texture Research Imaging Platform applies trabecular bone score (TBS) measurement principles to images acquired with multiple modalities to assess bone texture at various skeletal sites. This study aimed to assess the bone texture score in dual-energy X-ray absorptiometry-acquired lateral vertebral fracture assessment (VFA) images (BTSVFA), evaluate its reproducibility, and vertebral fracture discrimination ability. Subjects included 178 VF cases and 178 non-VF controls, 136 women and 42 men in each group, age 55–92 years, from two research centers. Cases and controls were matched for age (±5 years), body mass index (±5 kg/m2) and TBS. All participants underwent dual-energy X-ray absorptiometry TBS assessment from standard posterior-anterior lumbar spine scans and BTSVFA assessment. VF presence was determined using VFA images applying the Genant's method. BTSVFA was lower among fractured women compared to non-fractured (0.626 ± 0.109 vs 0.675 ± 0.099, p < 0.01), but not among men. In a binary logistic regression adjusted for study center and sex, for each SD lower BTSVFA, there was a 40% increase (OR 1.40, 95% CI (1.13–1.74)) in the risk of having a prevalent VF; area under the curve (95% CI) 0.616 (0.557–0.675). Inter-assessor and inter-centers ICCs for BTSVFA measurements were very good; 0.96 (0.64–0.99) and 0.98 (0.95–0.99), respectively. The BTSVFA precision (coefficient of variation) was 2.42%. This feasibility study demonstrates the potential to assess trabecular bone texture in lateral VFA images with good reproducibility. BTSVFA can discriminate between fractured and non-fractured women independent of their age, body mass index and TBS. In conclusion, BTSVFA, a potential trabecular texture assessment that excludes the posterior elements, may have value in fracture prediction or as a novel approach to be further investigated in spine surgery planning.

Differences in Hip Geometry Between Female Subjects With and Without Acute Hip Fracture: A Cross-Sectional Case-Control Study.

Background and PurposeAlthough it is widely recognized that hip BMD is reduced in patients with hip fracture, the differences in geometrical parameters such as cortical volume and thickness between subjects with and without hip fracture are less well known.Materials and MethodsFive hundred and sixty two community-dwelling elderly women with hip CT scans were included in this cross-sectional study, of whom 236 had an acute hip fracture. 326 age matched women without hip fracture served as controls. MIAF-Femur software was used for the measurement of the intact contralateral femur in patients with hip fracture and the left femur of the controls. Integral and cortical volumes (Vols) of the total hip (TH), femoral head (FH), femoral neck (FN), trochanter (TR) and intertrochanter (IT) were analyzed. In the FH and FN the volumes were further subdivided into superior anterior (SA) and posterior (SP) as well as inferior anterior (IA) and posterior (IP) quadrants. Cortical thickness (CortThick) was determined for all sub volumes of interest (VOIs) listed above.ResultsThe average age of the control and fracture groups was 71.7 and 72.0 years, respectively. The fracture patients had significantly lower CortThick and Vol of all VOIs except for TRVol. In the fracture patients, cortical thickness and volume at the FN were significantly lower in all quadrants except for cortical volume of quadrant SA (p= 0.635). Hip fracture patients had smaller integral FN volume and cross-sectional area (CSA) before and after adjustment of age, height and weight. With respect to hip fracture discrimination, cortical volume performed poorer than cortical thickness across the whole proximal femur. The ratio of Cort/TrabMass (RCTM), a measure of the internal distribution of bone, performed better than cortical thickness in discriminating hip fracture risk. The highest area under curve (AUC) value of 0.805 was obtained for the model that included THCortThick, FHVol, THRCTM and FNCSA.ConclusionThere were substantial differences in total and cortical volume as well as cortical thickness between fractured and unfractured women across the proximal femur. A combination of geometric variables resulted in similar discrimination power for hip fracture risk as aBMD.

POS-582 ASSOCIATION BETWEEN T SCORES, FRAX SCORES, FRAILTY, FALLS, AND FRACTURES IN PATIENTS UNDERGOING MAINTENANCE HEMODIALYSIS

Despite the magnitude and consequences of fracture in hemodialysis patients, optimal risk assessment tools in this population are not well explored. Frailty and falls—known risk factors for fracture—are common in hemodialysis patients. While the relationship between T scores in relation to fractures in these patients is recognized, there is a paucity of data to the additional contributions of fracture assessment tool (FRAX), frailty, and falls in relation to fractures. Therefore, we intended to evaluate the clinical utility of adding these factors to T scores at the femoral neck to determine whether it enhances fracture discrimination in hemodialysis patients.

Better discrimination of the concomitant peri-ankle fractures in the spiral tibial shaft fractures by thin-slice axial and three-dimensional CT.

The objective of this study was to examine the morphologic features of spiral tibial shaft as well as concomitant fibular and peri-ankle fractures on multidetector high-resolution CT and to speculate about the mechanisms underlying these combined fractures.This is a retrospective cohort study. A total of 197 tibial shaft fractures underwent multidetector high-resolution CT before intramedullary nailing. The presence and location of peri-ankle fractures were recorded using thin-slice axial CT. Tibial shaft fractures were classified as spiral or non-spiral. The morphologies of spiral tibial fractures and concomitant lateral malleolar fractures were delineated using three-dimensional CT.Seventy-five spiral and 122 non-spiral fractures were identified. Peri-ankle fractures excluding lateral malleolar fractures were found in 77.3% of spiral fractures and 18.9% of non-spiral fractures. The most frequent location of peri-ankle fractures in the spiral group was the posterior malleolus, followed by the anterolateral distal tibia, while the medial malleolus was the most frequent site in the non-spiral group. Of 75 spiral fractures, 72 showed a fracture morphology attributed to external rotation force. There were 13 lateral malleolar fractures that were defined as within 6 cm from the distal end of the fibula. No lateral malleolar fractures showed the typical morphology of isolated supination/external rotation-type ankle injuries. The displaced syndesmotic injuries commonly coexisting in pronation/external rotation-type ankle injuries were not observed.Most spiral tibial shaft fractures were caused by external rotation force. However, the morphology of concomitant peri-ankle fractures was inconsistent with typical mechanisms of isolated external rotation ankle injuries.

Morphological analysis of coronal femoral intertrochanteric fracture and its effect on reduction and internal fixation

To investigate the morphology of coronal femoral intertrochanteric fracture and its effect on reduction and internal fixation. The clinical and imaging data of 46 patients with femoral intertrochanteric fracture who met the selection criteria between August 2017 and October 2018 were reviewed. There were 15 males and 31 females; the age ranged from 62 to 91 years, with an average of 72.8 years. The causes of injury included walking falls in 35 cases, falling out of bed in 4 cases, and traffic accidents in 7 cases. The AO/Orthopaedic Trauma Association classification was type 31-A1 in 11 cases and type 31-A2 in 35 cases. All patients underwent closed reduction and internal fixation with intramedullary nails. During the operation, fracture reduction and fixation were performed according to the preoperative evaluation results. According to the patients' preoperative X-ray film and CT three-dimensional reconstruction images, the direction of the coronal fracture line of the femoral intertrochanter and the morphological characteristics of the fracture block were observed; and the coronal fracture discrimination analysis was carried out for the fractures of different AO/OTA types. The percentages of coronal femoral intertrochanteric fractures diagnosed by preoperative X-ray film and CT three-dimensional reconstruction were calculated and statistically analyzed. The fracture reduction, the position of internal fixation [measurement of tip-apex distance (TAD)]. and the reliability of internal fixation were observed after operation. X-ray film was not easy to identify coronary fracture, and the coronal fracture line and the shape of the fracture piece weree clearly visible in CT three-dimensional reconstruction images. The morphological characteristics of the coronary fracture block: in AO/OTA 31-A1 type, the fracture line extended obliquely backward from the anterior tip of the large rotor, above the small rotor with or without small rotor fracture; in AO/OTA 31-A2 type, fracture line extended obliquely backward from the anterior tip of the large rotor to below the small rotor. Thirteen cases (28.3%) of coronal fractures were found on preoperative X-ray films, and 35 cases (76.1%) were found by CT three-dimensional reconstruction, showing significant difference ( χ 2=21.083, P=0.000). In AO/OTA 31-A1 type patients, the proportion of coronal fractures found by X-ray film and CT three-dimensional reconstruction was 18.2% (2/11) and 54.5% (6/11), respectively, and that in AO/OTA 31-A2 type patients was 31.4% (11/35) and 82.9% (29/35), respectively, showing significant differences ( χ 2=3.143, P=0.000; χ 2=20.902, P=0.000). Among the 35 patients with coronal fractures, 6 cases (17.1%) of AO/OTA 31-A1 type, 29 cases (82.9%) of AO/OTA 31-A2 type. The operation time of the patient was 80-112 minutes, with an average of 95 minutes; the intraoperative blood loss was 180-450 mL, with an average of 360 mL. There was no complication such as infection, falling pneumonia, and deep vein thrombosis of the lower extremities. At 3 days after operation, the internal fixators were all in the proper position. The TAD was 0.9-1.8 cm, with an average of 1.4 cm. All patients were followed up 14-18 months, with an average of 16 months. All the fractures healed osseously, and there was no complication such as nonunion and loosening of internal fixation. CT three-dimensional reconstruction can better identify coronal femoral intertrochanteric fractures than X-ray films, and accurately recognize and analyze the incidence and morphological characteristics of coronal fractures, which can help formulate more effective surgical strategies to promote patient recovery.

Performance of HR-pQCT, DXA, and FRAX in the discrimination of asymptomatic vertebral fracture in postmenopausal Chinese women

SummaryVolumetric bone density (vBMD) and trabecular microarchitecture measured by high-resolution peripheral quantitative computed tomography (HR-pQCT) can discriminate the patients with high risk of asymptomatic vertebral fracture (VF) in postmenopausal Chinese women. These findings suggested that HR-pQCT could provide additional information on bone quality of the patients with asymptomatic VF.IntroductionAlthough there were several studies using HR-pQCT to investigate asymptomatic VF, it remains uncertain if HR-pQCT parameters can discriminate asymptomatic VF patients, especially in Chinese population. The purpose of this study was to investigate whether bone quality measured by HR-pQCT could discriminate asymptomatic VF independent of hip areal bone mineral density (aBMD) measured by dual-energy x-ray absorptiometry (DXA) and fracture risks evaluated using built-in Fracture Risk Assessment Tool (FRAXBMD).MethodsThis is a nested case–control study. One hundred seventy-five ambulatory Chinese postmenopausal women aged 60–79 years were retrieved from Normative Reference Standards (NRS) cohort in Hong Kong. DXA was used to identify VF from lateral spine images (VFA) using Genant’s semi-quantitative method. Major osteoporotic fracture risk was calculated using FRAX tool. HR-pQCT was used to assess vBMD, microarchitecture, and estimated strength at both distal radius and tibia. Comparison of HR-pQCT parameters between asymptomatic VF and control was performed using covariance analysis. Logistic regression analysis was performed for calculating the adjusted odds ratio (OR) with 95% confidence intervals (CI) of fracture status as per SD decrease in HR-pQCT parameters.ResultsWomen with asymptomatic VF were older than those of the control in our NRS cohort. Nevertheless, after adjusted for covariance, asymptomatic VF showed significantly lower trabecular vBMD (Tb.vBMD) at radius but higher SMI at tibia as compared with those of the control. Tb.vBMD at radius yielded the highest value of area under the curve (AUC) as compared with total hip aBMD and FRAXBMD. However, no significant difference was found among each other.ConclusionTb.vBMD at the radius and SMI at the tibia provided by HR-pQCT can discriminate asymptomatic VF independent of hip aBMD and FRAXBMD by DXA in postmenopausal women.

Structural Factors Associated With Femoral Neck Fractures and its Prediction in Chinese Males

We have recently proposed a new approach to evaluate 2D femoral neck (FN) structure, named the Minimal Model (MM), that comprised FN areal bone mineral density (FNaBMD) and FNWidth and 2 new internal structural measures; (1) the standard deviation of normalized mineral mass projection profile distribution (FNSigma), and (2) the displacement between center-of-mineral mass and geometric center of mineral mass projection profile (FNDelta). The contralateral hip of 67 FN fracture Chinese male patients had a QCT scan shortly after fracture and was compared to 156 community participants without hip fracture. The QCT scans were analyzed using Mindways software to enable DXA-equivalent 2D images to be obtained; MM variables were calculated from these images. In FN fracture and nonfracture participants, the 4 MM variables as well as age, weight and height were compared. Compared to nonfracture, fracture participants were older, weighed less and were taller. After adjustment for these differences FN fracture participants compared to nonfracture had mean ± SD lower FNaBMD 0.54 ± 0.11 vs 0.70 ± 0.11 g/cm2 (p < 0.001); larger FNSigma 1.05 ± 0.11 vs 0.98 ± 0.10 cm (p < 0.001); larger FNDelta 0.43 ± 0.09 vs 0.33 ± 0.09 cm (p < 0.001), however FNWidth did not differ 2.96 ± 0.35 vs 2.92 ± 0.34 cm. All variables except FNaBMD and FNWidth were correlated; however logistic regression identified increased age and height, reduced FNaBMD and increased FNSigma as independent contributors to differentiating participants with FN fracture from nonfracture. Area under ROC analysis identified significant improvement in discrimination with addition of FNSigma to the base model of Age and FNaBMD (C statistic 0.88 and 0.91, p = 0.019). These analyses identified important internal structural information available from 2D DXA imaging that contributes to discrimination of FN fracture in addition to low bone mass. This analytical approach may contribute to improved clinical FN fracture prediction, extending value of widely available DXA technology.

Practice of High-density 3D Seismic Exploration in Tight Oil Exploration in G Area of Central Sichuan

The Oil reservoir in Jurassic of Sichuan Basin is tight, thin, high heterogeneity, complex sand distribution and well-developed micro-fault etc., whose difference of buried depth is up to 2000m from south to north. The vertical and lateral resolution of conventional seismic exploration is too low to predict reservoir clearly, which restrains further development of close oil exploitation in central of Sichuan Basin. Lots of examples shows that high density acquisition is able to improve the description ability of seismic data, In G area of Sichuan Basin, a high-density, high-fold, small-cell, full-azimuthal 3D acquisition has been tested, which is the first mountainous high-density seismic exploration in China. In view of mass data and difficult geological target, a processing technique series including auto-first-break-picking, pre-stack noise suppression, robust surface consistent deconvolution, pre-stack time migration in OVT (Offset Vector Tile) field is applied to obtain high quality image. Analysis of multiple geological target results revealed that, the high-density data has fair higher signal-to-noise ratio, much wider bandwidth with more information, much better vertical and lateral resolution, which increased the identification of sand boundary, predication of thin reservoir, discrimination of micro-fault and fracture, recognition of sub geological features. It is well provided that high-density 3D seismic exploration has vast application future in close oil exploitation.

Muscle density is better than bone density in the discrimination of incident hip fracture: a propensity score matching study

Muscle density is better than bone density in the discrimination of incident hip fracture: a propensity score matching study