Search Results (12)

Background/Objectives: The global population of individuals aged ≥ 80 years is rapidly growing, leading to an increasing incidence of cancer diagnoses in this age group. While stereotactic body radiotherapy (SBRT) has proven effective in treating pulmonary oligometastases, patients over 80 remain underrepresented in clinical analyses. This study aimed to evaluate clinical outcomes and toxicity of SBRT for pulmonary oligometastases in octogenarians. Methods: This retrospective, single-centre analysis included 34 patients aged ≥ 80 years treated with SBRT for histologically confirmed pulmonary oligometastases between 2010 and 2024. Results: A total of 46 pulmonary metastases were treated with curative intent using fractionation schemes of 3 × 15 Gy, 6 × 8 Gy, or 10 × 6 Gy. Median biologically effective dose (BED10) was 112.5 Gy. Follow-up included regular CT imaging and toxicity assessment according to CTCAE. With a median follow-up of 22.6 months, 1-, 2-, and 3-year local control (LC) rates were 95.2%, 95.2%, and 90.2%, respectively. Median overall survival (OS) was 46.6 months, with 1-, 2-, and 3-year OS rates of 78.4%, 71.4%, and 59.5%. Progression-free survival (PFS) at 1, 2, and 3 years was 63.4%, 51.6%, and 47.3%, respectively. No grade ≥ 3 toxicities were observed. Grade 2 pneumonitis and dermatitis occurred in 2.9% each and were well managed. Asymptomatic rib fractures were detected in 5.9% of patients. No significant predictors for LC, PFS, or OS were identified in univariate analysis. Conclusions: SBRT for pulmonary oligometastases in patients ≥ 80 years is feasible, safe, and effective. High local control, favourable cancer-specific survival, and minimal toxicity support its use as a curative-intent treatment in this growing patient population. These findings contribute important site- and age-specific evidence and support the inclusion of very elderly patients in future prospective SBRT trials. Full article

Background/Objectives: Effective pain management in polytrauma patients with rib fractures is essential, particularly in the critical care setting. While epidural analgesia is considered the gold standard, it is not always feasible, necessitating alternative locoregional approaches. We present the case of a polytrauma patient with multiple, bilateral rib fractures and severe chest pain that hindered weaning from mechanical ventilation. A bilateral Serratus Anterior Plane Block (SAPB) was performed, with catheters placed for continuous administration of local anesthetics. Pain relief was immediate, enabling a rapid weaning from mechanical ventilation, safe extubation, and subsequent discharge to rehabilitation. A review of the literature on this technique in critically ill patients with thoracic trauma and multiple rib fractures is also presented. Methods: We conducted a literature search up to November 2024, identifying studies evaluating the use of SAPB in critically ill patients with chest trauma and rib fractures. Results: Eight studies were identified, including a total of 197 cases, of which only 3 involved a bilateral SAPB. Studies and published case reports demonstrated significant variability in analgesic protocols and reported outcomes. Notably, only two papers addressed specifically its role in facilitating weaning from mechanical ventilation. Conclusions: Pain control is fundamental in managing severe chest trauma. This case and the reviewed literature suggest that the SAPB is a promising option when epidural analgesia is contraindicated or impractical. However, further studies are needed to define its place in clinical practice and optimize its use in critically ill patients. Full article

Background: Osteoporosis-related fragility fractures are increasing worldwide. An assessment of the prevalence of fragility fractures in Bahrain is needed to determine proper action and preventive strategies. The main objective of this study was to conduct a retrospective cross-sectional study to investigate the prevalence of fragility fractures in adult Bahraini patients. Another objective was to explore the relationship of fragility fracture risk with BMD, age, sex, BMI, vitamin D status, and therapy. Methods: To investigate the fragility fractures, we retrospectively reviewed the dual-energy X-ray absorptiometry (DEXA) data of patients who underwent scans for the diagnosis of osteoporosis between 2016 and 2018. The data were collected from four large centers in Bahrain. The patients’ medical records were reviewed for the fragility fracture data, BMD, sex, age, BMI, vitamin D status, and therapy. Results: Among a total of 4572 patients who visited the radiology departments during the 3-year study period, only 412 patients with fragility fractures were considered for the current study. The mean age of the patients in this cohort was 63.9 ± 12.2 years. There were 393 females (95.6%). Among the 431 fragility fractures, there were 175 (40.6%) belonging to three common fracture sites: vertebral (86, 20.9%), femur (60, 14.6%), and distal radius (Colles) fractures (29, 7%). Other fragility fractures were hand (7%), radius and ulna (3.7%), humerus (6.5%), tibia and fibula (5.6%), foot/ankle (27.9%), ribs (3.0%), and pelvis (1.6%). Our results revealed a significant association between the fragility fractures and BMD (χ² = 6.7, p = 0.035). We reported a significant association of fragility fracture with sex (p = 0.006) and with denosumab therapy (p < 0.001). Conclusions: This study reported a reduced BMD and an increased prevalence of fragility fractures among Bahraini subjects. The highest frequencies of fragility fractures among our cohort were foot/ankle, vertebral, and hip fractures, respectively. We showed a statistically significant association between fragility fractures and BMD. The current study indicated that not only patients with low BMD but also patients with fragility fractures were undertreated. Thus, the immediate initiation of treatment and the synthesis of local osteoporosis treatment guidelines are warranted. Full article

Background: Chest radiography is the standard method for detecting rib fractures. Our study aims to develop an artificial intelligence (AI) model that, with only a relatively small amount of training data, can identify rib fractures on chest radiographs and accurately mark their precise locations, thereby achieving a diagnostic accuracy comparable to that of medical professionals. Methods: For this retrospective study, we developed an AI model using 540 chest radiographs (270 normal and 270 with rib fractures) labeled for use with Detectron2 which incorporates a faster region-based convolutional neural network (R-CNN) enhanced with a feature pyramid network (FPN). The model’s ability to classify radiographs and detect rib fractures was assessed. Furthermore, we compared the model’s performance to that of 12 physicians, including six board-certified anesthesiologists and six residents, through an observer performance test. Results: Regarding the radiographic classification performance of the AI model, the sensitivity, specificity, and area under the receiver operating characteristic curve (AUROC) were 0.87, 0.83, and 0.89, respectively. In terms of rib fracture detection performance, the sensitivity, false-positive rate, and free-response receiver operating characteristic (JAFROC) figure of merit (FOM) were 0.62, 0.3, and 0.76, respectively. The AI model showed no statistically significant difference in the observer performance test compared to 11 of 12 and 10 of 12 physicians, respectively. Conclusions: We developed an AI model trained on a limited dataset that demonstrated a rib fracture classification and detection performance comparable to that of an experienced physician. Full article

Brown tumors, an exceptional bone complication of severe primary (PHP) or renal (secondary) hyperparathyroidism (RHP), are caused by long-standing, elevated parathormone (PTH)-induced osteoclast activation causing multinucleated giant cell conglomerates with hemosiderin deposits in addition to the local production of cytokines and growth factors. We aim to present an adult case series including two females displaying this complication as part of a multidisciplinary complex panel in high PTH-related ailments. The approach was different since they had distinct medical backgrounds and posed a wide area of challenges amid real-life settings, namely, a 38-year-old lady with PHP and long-term uncontrolled hypercalcemia (with a history of pregnancy-associated PHP, the removal of a cystic jaw tumor, as well as a family and personal positive diagnosis of polycystic kidney disease, probably a PHP-jaw tumor syndrome), as well as, a 26-year-old woman with congenital single kidney and chronic renal disease-associated RHP who was poorly controlled under dialysis and developed severe anemia and episodes of metabolic acidosis (including one presentation that required emergency hemodialysis and was complicated with convulsive seizures, followed by resuscitated respiratory arrest). Both subjects displayed a severe picture of PHP/RHP with PTH levels of >1000 pg/mL and >2000 pg/mL and elevated serum bone turnover markers. Additionally, they had multiple brown tumors at the level of the ribs and pelvis (asymptomatically) and the spine, skull, and pelvis (complicated with a spontaneous cervical fracture). As an endocrine approach, the control of the underlying parathyroid disease was provided via surgery in PHP (for the postparathyroidectomy hungry bone syndrome) via medical intervention (with vitamin D analogs) in RHP. Additionally, in this case, since the diagnosis was not clear, a multidisciplinary decision to perform a biopsy was taken (which proved inconclusive), and the resection of the skull tumor to confirm the histological traits. This series highlights the importance of addressing the entire multidisciplinary panel of co-morbidities for a better outcome in patients with PHP/RHP-related brown tumors. However, in the instance of real-life medicine, poor compliance and reduced adherence to recommendations might impair the overall health status. Thus, sometimes, a direct approach at the level of cystic lesion is taken into consideration; this stands for a narrow frame of decision, and it is a matter of personalized decision. As seen here, brown tumors represent the hidden face of PHP/RHP, primarily the complex and severe forms, and awareness is essential even in the modern era. Full article

Most cable arch bridge damage accidents are caused by bridge collapse due to fracture of the short sling of the arch bridge. The service life of the short sling is much lower than the design life, mainly resulting from the action of vehicles and temperature, and the arch rib and the bridge floor will have relative displacement along the bridge direction, which leads to the emergence of bending stress due to the different axes at both ends of the short sling, forming local stress concentration. The stress concentration is coupled with corrosion to accelerate the damage to the sling. To study the influence of shaft deflection on the mechanical properties of short slings of steel strands in arch bridges, this study analyzes the distribution law of the shaft deflection angle of arch bridge slings under the action of vehicle and temperature loads for a medium-bearing arch bridge with a main span of 560 m. The results show that under different vehicle and temperature loads, the axial deflection angle of the short sling is the largest, and the closer it is to the center of the span, the smaller the axial deflection angle. The static and fatigue properties of 1, 3, 7, 9, 12, 19, and 27 strands of whole bunch extruded strand slings were simulated and analyzed under a $0.45{\sigma }_b$ force when the axial deflection angle of the strand slings was 0 mrad, 10 mrad, 20 mrad, and 30 mrad. The results show that the ultimate tensile properties, breaking strength, and fatigue life of the strand slings decreased to a certain extent with increasing shaft deflection angle. The accuracy of the finite element models is verified by the ultimate tensile test and the fatigue test. This study explores the bending deflection results of the short slings of arch bridges due to the different axes of the upper and lower anchorages and provides the necessary theoretical support for the design and fatigue life estimation of the short slings of arch bridges. Full article

Discontinuum Bonded Block Modeling (BBM) represents a potential tool for support design, as these models can reproduce both the rock fracturing process and the influence of reinforcement on unsupported ground. Despite their strengths, discontinuum models are seldom used for mining design due to their computationally intensive nature. This study is an application of an integrated 3D continuum–2D discontinuum approach, in which the mine-wide stress distribution process is modeled using a continuum software, and the local deformation behavior in response to a strain path from the continuum model is simulated with a 2D discontinuum software. In June 2017, two multi-point borehole extensometers were installed in a longwall chain pillar to record ground displacements as a function of the longwall face position. The data from one of the extensometers were employed to calibrate a panel-scale FLAC3D model. The boundary conditions along the pillar slice containing the extensometer were extracted from the FLAC3D model and applied to a 2D BBM, and the input parameters were modified to match the extensometer data. The calibrated BBM was able to reproduce the unsupported rib deformation and depth of the fracturing well. Subsequently, a few support schemes were tested to demonstrate how the incorporation of support might affect rib deformation. Full article

Weld defects such as porosity, inclusion, burn-through, and lack of penetration are difficult to detect and control effectively in an orthotropic steel deck (OSD), which will be a fatigue crack initiation site and lead to several fatigue cracking. The crack growth behavior in defective welded joints is different from that of defect-free joints. This study investigates crack–inclusion interaction for rib-to-deck welded joints in OSDs based on numerical simulation and linear elastic fracture mechanics (LEFM). A refined finite element model of a half U-rib with cracks and inclusions was established by using the FRANC3D-ABAQUS interactive technology. The full processes of the crack–inclusion interaction from approaching and penetrating were accurately simulated. Critical parameters, including the stress intensity factor (SIF), the shape factor, the growth rate, and the growth direction were analyzed. The stiff and soft inclusions amplify and shield the SIF of cracks when the crack grows to the local area of inclusions. During the entire process of crack growth, the soft and stiff inclusion accelerate and inhibit the crack growth, respectively. The stiff inclusion will lead to asymmetric growth of the crack shape, where the portion of the crack away from the inclusions has a higher growth rate. The soft and stiff inclusions will attract and repel the direction of crack growth at the proximal point, respectively. Full article

In response to the large-scale instability failure problem of designing coal pillars and support systems for gob-side entry driving (GSED) in high-stress soft coal seams in deep mines, the main difficulties in the surrounding rock control of GSED were analyzed. The relationship between the position of the main roof breaking line, together with the width of the limit equilibrium zone and a reasonable size for the coal pillar, were quantified through theoretical calculations. The theoretical calculations showed that the maximum and minimum widths of the coal pillar are 8.40 m and 5.47 m, respectively. A numerical simulation was used to study the distribution characteristics and evolution laws of deviatoric stress and plastic failure fields in the GSED surrounding rock under different coal pillar sizes. Theoretical analysis, numerical simulation, and engineering practice were comprehensively applied to determine a reasonable size for narrow coal pillars for GSED in deep soft coal seams, which was 6.5 m. Based on the 6.5 m coal pillar size, the distribution of deviatoric stress and plastic zones in the surrounding rock of the roadway, at different positions of the advanced panel during mining, was simulated, and the range of roadway strengthening supports for the advanced panel was determined as 25 m. The plasticization degree of the roof, entity coal and coal pillar, and the boundary line position of the peak deviatoric stress zone after the stability of the excavation were obtained. Drilling crack detection was conducted on the surrounding rock of the GSED roof and rib, and the development range and degree of the crack were obtained. The key areas for GSED surrounding rock control were clarified. Joint control technology for surrounding rock is proposed, which includes a combination of a roof channel steel anchor beam mesh, a rib asymmetric channel steel truss anchor cable beam mesh, a grouting modification in local fractured areas and an advanced strengthening support with a single hydraulic support. The engineering practice showed that the selected 6.5 m size for narrow coal pillars and high-strength combined reinforcement technology can effectively control large deformations of the GSED surrounding rock. Full article

In the face of the difficulty in achieving high-quality integrated molding of longitudinally and transversely stiffened panels for helicopters by resin-matrix composite materials, we combine the prepreg process and the resin transfer molding (RTM) process to propose a hybrid resin transfer molding (HRTM) for composite stiffened panel structures. The HRTM process uses a mixture of prepreg and dry fabric to lay up a hybrid fiber preform, and involves injecting liquid resin technology. Using this process, a longitudinally and transversely stiffened panel structure is prepared, and the failure modes under compressive load are explored. The results show that at the injection temperature of the RTM resin, the prepreg resin dissolves slightly and has little effect on the viscosity of the RTM resin. Both resins have good miscibility at the curing temperature, which allows for the overall curing of the resin. A removable box core mold for the HRTM molding is designed, which makes it convenient for the mold to be removed after molding and is suitable for the overall molding of the composite stiffened panel. Ultrasonic C-scan results show that the internal quality of the composite laminates prepared using the HRTM process is good. A compression test proves that the composite stiffened panel undergoes sequential buckling deformation in different areas under compressive load, followed by localized debonding and delamination of the skin, and finally failure due to the fracture of the longitudinal reinforcement ribs on both sides. The compressive performance of the test specimen is in good agreement with the finite element simulation results. The verification results show that the HRTM process can achieve high-quality integrated molding of the composite longitudinally and transversely stiffened panel structure. Full article

Computed tomography (CT) images play a vital role in diagnosing rib fractures and determining the severity of chest trauma. However, quickly and accurately identifying rib fractures in a large number of CT images is an arduous task for radiologists. We propose a U-net-based detection method designed to extract rib fracture features at the pixel level to find rib fractures rapidly and precisely. Two modules are applied to the segmentation network—a combined attention module (CAM) and a hybrid dense dilated convolution module (HDDC). The features of the same layer of the encoder and the decoder are fused through CAM, strengthening the local features of the subtle fracture area and increasing the edge features. HDDC is used between the encoder and decoder to obtain sufficient semantic information. Experiments show that on the public dataset, the model test brings the effects of Recall (81.71%), F1 (81.86%), and Dice (53.28%). Experienced radiologists reach lower false positives for each scan, whereas they have underperforming neural network models in terms of detection sensitivities with a long time diagnosis. With the aid of our model, radiologists can achieve higher detection sensitivities than computer-only or human-only diagnosis. Full article

Bone fracture healing involves the combination of intramembranous and endochondral ossification. It is known that Indian hedgehog (Ihh) promotes chondrogenesis during fracture healing. Meanwhile, Sonic hedgehog (Shh), which is involved in ontogeny, has been reported to be involved in fracture healing, but the details had not been clarified. In this study, we demonstrated that Shh participated in fracture healing. Six-week-old Sprague–Dawley rats and Gli-CreER^T2; tdTomato mice were used in this study. The right rib bones of experimental animals were fractured. The localization of Shh and Gli1 during fracture healing was examined. The localization of Gli1 progeny cells and osterix (Osx)-positive cells was similar during fracture healing. Runt-related transcription factor 2 (Runx2) and Osx, both of which are osteoblast markers, were observed on the surface of the new bone matrix and chondrocytes on day seven after fracture. Shh and Gli1 were co-localized with Runx2 and Osx. These findings suggest that Shh is involved in intramembranous and endochondral ossification during fracture healing. Full article