Search Results (440)

Background: Distal radius fractures (DRFs) are common fragility fractures often associated with underlying osteoporosis. Objective: To evaluate the effect of nutraceutical supplementation in addition to pulsed electromagnetic field (PEMF) therapy on pain and early fracture healing. Methods: Sixty female patients were randomized into two groups: Group A received PEMF therapy alone, while Group B received PEMF plus nutraceutical supplementation. The primary outcome was pain reduction (NRS). Secondary outcomes included biochemical markers and ultrasound-based callus formation. Results: At T1, Group B showed a trend toward greater pain reduction compared with Group A (mean difference −0.57; p = 0.007) and higher bone alkaline phosphatase levels (p = 0.0002). A higher proportion of patients reached minimal clinically important difference (MCID) in Group B (60% vs. 30%, p = 0.02). Conclusions: Nutraceutical supplementation in addition to PEMF was associated with improved short-term outcomes; however, due to the absence of a non-PEMF control group, the independent effect of PEMF cannot be determined. Full article

To address the widespread issue of abnormally high pump pressure during hydraulic fracturing of deep-to-ultra-deep reservoirs (burial depth > 4500 m) in the Junggar Basin, this study systematically reveals the mechanical mechanism underlying this phenomenon by integrating well logging curve analysis and elastoplastic mechanics theory. Statistical results demonstrate that the actual fracture initiation pressure of 60% of wells in the target block is significantly higher than the values predicted by traditional elastic theory, primarily attributed to plastic yielding and stress concentration effects around perforations induced by high in situ stress. An elastoplastic rock fracture initiation pressure model is established based on the Mohr–Coulomb criterion and the plastic zone radius criterion, which is applied to predict the fracture initiation pressure of selected wells in the target block. The relative error between the model predictions and field measurements is less than 2%, significantly improving the prediction accuracy of fracture initiation pressure in deep-to-ultra-deep formations. This provides precise guidance for subsequent optimization of operational parameters and selection of pressure ratings for wellhead equipment. The study further clarifies that in situ stress difference, rock yield stress, and the power-law hardening exponent are the key factors controlling the transition of fracture initiation modes. To mitigate the high pump pressure challenge in deep-to-ultra-deep reservoir fracturing, the field application of weighted fracturing fluid effectively increases the wellbore hydrostatic column pressure, reduces wellhead operational pressure, and ensures construction safety. The findings of this study provide critical theoretical and technical support for achieving the goal of “successful fracture initiation and effective fracture control” in deep-to-ultra-deep reservoir fracturing. Full article

Background: Distal radius fractures (DRFs) are the most common upper limb fractures worldwide. The main goal of DRF treatment is to achieve optimal functional outcomes with the lowest complication rate as rapidly as possible. Achieving full limb function may be delayed by emerging complications or, in some cases, may never occur. Preserving muscle strength and as full a range of motion (ROM) in the wrist as possible are key in DRF management since they enable patients to perform the activities of daily living. The purpose of this study was to assess the effect of ossein–hydroxyapatite complex (OHC), used as an adjunct in conservative DRF treatment, on muscle strength and ROM. Methods: This was a prospective randomized clinical study. We assessed 31 patients who underwent non-surgical DRF treatment at our center in the years 2024–2025 and were receiving OHC throughout their fracture treatment. K-Grip and K-Push dynamometers were used to measure the maximum and average muscle strength via tests of grip strength, palmar flexion, and dorsal flexion. Wrist ROM was also evaluated. The results were compared with those of the control group (31 patients receiving DRF treatment without OHC) and with the intact limb. Results: The medians of the maximum muscle strength in each test were comparable between the study groups. Both groups showed a higher median average strength in the intact limb than in the treated limb. We observed no intergroup differences in wrist ROM, with ROM parameters lower in the fractured limb than in the intact limb. Conclusions: The additional use of OHC was not associated with statistically significant improvements in functional outcomes. The patients from both groups achieved worse muscle strength and ROM outcomes in the fractured than in the intact limb. We recommend a longer and more intense rehabilitation of patients with DRFs. More studies on this topic are needed in order to unequivocally verify the effects of OHC on functional parameters in fracture patients. Full article

Background: Forearm fractures involving both bones are common orthopedic injuries. Children have a higher tolerance for greater displacement and angulation owing to the remodeling potential. The optimal fixation method for managing pediatric forearm fractures has not been definitively established. This study evaluated the safety and efficacy of a stepwise surgical algorithm, wherein single-bone plating was attempted first, and both-bone fixation was strictly reserved for cases demonstrating persistent intraoperative instability. Methods: In this retrospective analysis, we evaluated 48 skeletally immature children with both-bone forearm fractures managed via our stepwise protocol. Initially, single-bone plating was performed. Dynamic manual stress testing was then applied under fluoroscopy. If the unplated bone exhibited rotational instability, residual angulation >15°, or translation >50%, the procedure was converted to both-bone plating (Group B, n = 16). Patients who achieved stable alignment without requiring a second plate formed Group A (n = 32). Results: Both groups achieved 100% union. Postoperative angulations of the radius on the anteroposterior view were 1.91 ± 2.73° in Group A and 0.88 ± 1.96° in Group B; meanwhile, the lateral angulation of the radius in Groups A and B was 1.88 ± 3.56° and 0.00 ± 0.00°, respectively. The anteroposterior angulation of the ulna was 2.31 ± 3.60° in Group A and 2.19 ± 4.00° in Group B, whereas the lateral angulation of the ulna was 2.81 ± 3.74° in Group A and 1.75 ± 3.47° in Group B. Only the lateral angulation of the radius showed a significant difference (p = 0.0418). In the subgroup analysis, minor differences in ulna angulation on the anteroposterior view reached statistical significance in the older cohort (p = 0.027) and in the distal-third fracture group (p = 0.001). No differences in bone healing or functional outcomes were observed, and complication rates were similar. Conclusion: Our stepwise surgical algorithm appears to be a safe and effective approach. By adhering to this protocol, 66.7% of patients were successfully spared the morbidity of a second incision, while all patients achieved solid union and excellent functional outcomes. However, further high-quality studies are essential to establish comprehensive protocols for intraoperative stability assessment and postoperative care. Full article

Background and Clinical Significance: Acute compartment syndrome is a rare but limb-threatening emergency in pediatric patients. While most cases follow high-energy trauma or displaced fractures, acute compartment syndrome precipitated by initially underestimated forearm injuries is uncommon and may create a significant diagnostic challenge, particularly in young children who exhibit atypical clinical presentations, such as escalating anxiety and analgesic requirements, rather than classic ischemic signs. Case Presentation: We report the case of a 4-year-old girl who developed severe forearm and hand compartment syndrome following a delayed presentation after a fall from a height of 2–2.5 m onto the left upper extremity. Initial evaluation revealed progressive tense swelling, severe pain with passive stretch, diminished distal perfusion, and radiographic evidence of distal radius-ulna buckle fractures associated with a proximal ulna fracture. Emergent surgical decompression via extensive volar and dorsal fasciotomies revealed markedly elevated compartment pressures. Intraoperatively, deep volar muscle ischemia and necrosis were identified, requiring carpal tunnel release, serial debridements, and complex staged wound management. Multidisciplinary care and ongoing rehabilitation were essential for limb salvage and functional recovery. Conclusions: This case underscores the profound unpredictability of pediatric compartment syndrome and demonstrates that even classically stable, benign fractures can initiate a devastating ischemic cascade. A high index of suspicion, regardless of the injury mechanism, along with early recognition and prompt surgical intervention, is absolutely critical for preventing irreversible myoneural damage and optimizing management outcomes in pediatric patients. Full article

Underground fluid injection is regarded as one of the important factors inducing seismic activity. This study therefore proposes a method to predict the maximum damage area and seismic magnitude induced by fluid injection, in order to quantify the relationship between stress disturbances in faults and induced seismic activity during fluid injection. This method involves analysing a three-dimensional geological model of fault permeability evolution in order to define the seismic rupture zone of faults during fluid injection projects. It also involves calculating the maximum damage area and seismic magnitude induced by injection and verifying the method’s effectiveness using field data. The results show that, during deep injection, continuous injection of fluid reduces the effective stress on the fault and increases the fracture area. Following the sudden cessation of injection, the rupture area and maximum seismic magnitude reach their peak values. During the initial stage of injection, seismic magnitude increases rapidly with the rupture radius of the fault, while the growth rate of seismic magnitude decreases during the stable injection stage. Once injection has ceased, the rupture range and seismic magnitude will gradually stabilise throughout the entire geological self-balancing stage. Periodic injection results in the largest fault rupture area, whereas linear growth injection induces the highest seismicity. Strike-slip faults exhibit the most significant increase in rupture area, whereas normal faults demonstrate more intense seismicity evolution. Low permeability, proximity to injection wells and direct well closure exacerbate instability, whereas linear slow closure is the safest option. These research results can inform seismic risk management in fluid injection engineering. Full article

A transverse fracture occurred in U75V pearlitic rail after 5 months of service on a sharp radius curved track of mixed passenger-freight railway. Systematic tests including chemical composition analysis, mechanical properties testing, macroscopic fracture inspection, metallographic observation and microscopic morphology characterization were conducted on the failed rail sample. The results indicate that the rail base metal has qualified metallurgical quality. Its chemical composition, fundamental mechanical properties and microstructure fully meet the requirements of Chinese railway standard TB/T 2344.1-2020. The failure mode is identified as instantaneous brittle fracture. Severe mechanical extrusion and impact cause prominent plastic deformation on the rail foot, leading to surface plastic flow and further triggering micro-crack initiation. Under continuous cyclic stress induced by train loads, the micro-crack tips undergo repeated tearing and closing. Severe stress concentration accelerates the formation of transgranular cracks, which propagate rapidly and unstably toward the rail interior, eventually resulting in catastrophic transverse fracture. Standardized procedures in rail transportation, hoisting and laying are essential to avoid mechanical damage, while regular line inspection and timely replacement of damaged rails should be strictly enforced. Full article

Background: Primary hyperparathyroidism (PHPT) has undergone notable clinical changes over recent decades, with asymptomatic cases now prevailing in Western countries. In contrast, a broad spectrum of clinical manifestations remains common in Romania, an Eastern European country. This study aims to provide a representative descriptive analysis of clinical presentations and related complications observed in this setting. Methods: We performed a cross-sectional, single-center study of 413 consecutive PHPT cases diagnosed between 2000 and 2020 at a tertiary endocrinology center in Romania. Data included demographics, clinical features, biochemistry, bone turnover markers, 25OHD, BMD by DXA, TBS, fractures, renal involvement, and etiology. Results: Patients were predominantly female (88.6%), with a mean age of 60 ± 11.7 years and a mean BMI of 27.3 ± 5.7 kg/m². Familial forms were identified in 4.4%. Mean serum calcium was 11.28 ± 1.09 mg/dL, mean PTH 248.31 ± 361.94 pg/mL, and mean 25OHD 17.95 ± 9.6 ng/mL. Symptomatic hypercalcemia was present in 23.2% and severe vitamin D deficiency in 21%. Fractures were present in 25.2% and osteitis fibrosa cystica in 1.7%. Mean T-scores (SD): LS –2.23, FN –1.85, 1/3 distal radius –1.96. Osteoporosis prevalence: LS 47%, FN 24.1%, 1/3 distal radius 38%. Mean TBS was 1.258 ± 0.115. Renal involvement included calcifications (56.7%), nephrolithiasis (53%), nephrocalcinosis (3.6%), hypercalciuria (31.7%), and reduced renal function (9.93%). Non-classical manifestations were mainly cardiovascular (58%) and osteoarticular (24.5%). Parathyroidectomy was performed in 217 patients (53%); histopathology showed adenoma (88.8%), carcinoma (5.2%), and hyperplasia (6%), with a mean adenoma weight of 2.86 ± 5.92 g. Conclusions: PHPT in Romania shows a heterogeneous phenotypic spectrum, reflecting variability in clinical presentation and suggesting an evolving epidemiological profile. Full article

This study investigated the high-temperature (600 °C, 650 °C, 700 °C, 750 °C and 800 °C) mechanical property and failure analysis of GH2070P alloy in boiler elbow pipe. The results show that the microstructures of GH2070P alloy at three typical positions (outer radius (OR), middle radius (MR) and inner radius (IR)) of the bent pipe exhibit distinct gradient features to some degree, and the unsignificant difference in the morphology and composition of the second phase can be found in OR, MR and IR. Below 700 °C, the mechanical properties at different positions show differences affected by the stress states of different positions. Among them, the tensile strength and yield strength of OR under tensile stress states are lower than those of IR under compressive stress states at the same temperature. However, above 700 °C, the mechanical properties of the three positions show no significant difference, which is related to stress release at high temperatures. From 700 °C to 800 °C, the degree of brittle fracture of the material increases, which is related to the performance degradation caused by the coarsening of the second phase at high temperatures. It is worth noting that within the temperature range of less than 700 °C, the yield strength increases with the rise in temperature, while the tensile strength and plasticity remain at a certain level without decreasing. This indicates that the GH2070P alloy has good service performance at 700 °C. Full article

Background/Objectives: Wrist fractures are common paediatric injuries, yet some remain radiographically occult. The Pronator Quadratus Sign (PQS), defined by displacement or alteration of the fat stripe overlying the pronator quadratus muscle (PQm), remains a debated radiologic diagnostic marker. This study evaluated whether PQS can serve as a diagnostic adjunct for wrist fractures and whether specific PQS morphological types are associated with different fracture patterns. Methods: This retrospective study included paediatric patients presenting with wrist trauma. Radiographs were categorized into three groups: no fracture, torus fracture, and other non-displaced distal radius fractures. PQS morphology was classified using a six-tier system. Quantitative assessment included measurement of the anterior distance from the distal radius to the external border of the pronator quadratus muscle (X) and radial width (R), expressed as the X/R ratio to standardize comparisons. Results: A total of 247 patients were included. The X/R ratio differed significantly among groups (p < 0.001), with higher values observed in patients with fractures. ROC analysis demonstrated good discrimination performance between no fracture and non-displaced distal radius fractures (AUC = 0.80), but limited performance for torus fractures (AUC = 0.62). Although PQS morphology alone was not a reliable indicator of fracture presence, the distribution of PQS types—representing distinct patterns of pronator quadratus fat stripe appearance and displacement—differed significantly across fracture groups (p < 0.001). Conclusions: Quantitative PQS assessment using the X/R ratio is associated with improved discrimination for non-displaced distal radius fractures, while PQS morphology alone shows limited diagnostic utility. Further prospective studies incorporating magnetic resonance imaging are warranted to clarify its role in occult fracture detection. Full article

In shale gas extraction, solid particles such as fracturing proppants cause erosion in production and transmission pipelines. Cyclone desanders are widely used for gas–solid separation, but high-velocity sand-laden fluids frequently induce equipment failure, leakage and safety risks. Therefore, research on erosion and protective measures is essential. This study focuses on the desander at the M shale gas wellhead, where wall thickness was measured at three monitoring points to determine erosion rates. A CFD-based numerical erosion model for the cyclone desander was developed using ANSYS Fluent within the ANSYS Workbench 19.2 environment (ANSYS, Inc., Canonsburg, PA, USA). The model was validated by comparing simulation results with field data, revealing the distribution patterns of the velocity field, pressure field, and erosion rate. The study analyzed the impact of nine factors on desander erosion: inlet aspect ratio, cylinder radius, cone length, dust discharge port diameter, exhaust port diameter, particle size, particle concentration, inlet velocity, and operating pressure, clarifying the erosion variation patterns for each factor. SPSSAU V25.0 (Beijing Qingsi Technology Co., Ltd., Beijing, China) was employed to analyze the significance of these nine factors, identifying six significant influencing factors: inlet aspect ratio, cylinder diameter, dust discharge port diameter, particle size, particle concentration, and inlet velocity. Subsequently, response surface analysis was performed using Design-Expert 13 (Stat-Ease, Inc., Minneapolis, MN, USA) to obtain the relationship between the factors and their impact on maximum erosion, leading to the establishment of a predictive model for the maximum erosion rate. In addition, geometry optimization, local wall thickening, coating protection, material selection, and bionic rib structures were discussed as erosion-mitigation strategies. The optimized geometry reduced the erosion rate at the inlet and dust discharge outlet by 20.4% and 21.8%, respectively, while the bionic rib structure reduced the maximum erosion rate by 58%. Full article

Background and Objectives: Pediatric forearm fractures are among the most common childhood injuries. COVID-19-related societal restrictions, including school closures and suspension of sports activities, altered children’s daily routines and may have influenced injury patterns. This study aimed to evaluate whether periods of stricter COVID-19 restrictions were associated with changes in the incidence of pediatric distal and diaphyseal forearm fractures after accounting for seasonal variation and long-term temporal trends. Materials and Methods: This retrospective observational time-series study analyzed pediatric patients aged 0–17 years who underwent forearm radiography between January 2018 and June 2023 at a tertiary pediatric trauma center. Cases with radiologically confirmed distal or diaphyseal forearm fractures or epiphyseal injuries were included. Monthly fracture counts were analyzed using generalized linear models with logarithmic link functions. Exposure variables included a COVID-19 restriction index based on governmental measures and a binary pandemic indicator. Seasonal variation and long-term temporal trends were included as covariates. Results: A total of 5702 forearm radiographs were identified, of which 4041 trauma-related presentations met the inclusion criteria. Among these, 2014 children had confirmed forearm fractures. Boys accounted for 61% of cases, and the median age was 9 years (IQR 5). Most fractures were treated conservatively (88%). The most frequent injury mechanisms included soccer-related injuries (9.6%) and bicycle falls (7.3%). In regression analyses adjusted for seasonal variation and temporal trends, neither the COVID-19 restriction index (IRR 1.01, 95% CI 0.87–1.17; p = 0.95) nor the pandemic period indicator (IRR 0.99, 95% CI 0.37–2.65; p = 0.98) was significantly associated with monthly fracture counts. The wide confidence interval of the pandemic indicator reflects limited statistical precision and suggests that both clinically relevant decreases and increases in fracture incidence cannot be excluded. Conclusions: No sustained long-term changes in the incidence or injury patterns of pediatric forearm fractures were observed during the COVID-19 pandemic. Temporary fluctuations during early lockdown phases were not independently associated with governmental restrictions after adjustment for seasonal variability and long-term trends. Full article

External skeletal fixation (ESF) is a versatile method for fracture management in neonatal calves but confers a significant risk of iatrogenic injury to vital structures. The aim of this ex vivo study was to systematically define safe, hazardous, and unsafe corridors for transcortical pin placement in the distal long bones (radius-ulna, tibia, metacarpus, and metatarsus) of Simmental calves to provide precise anatomical guidance. Six fresh Simmental calf cadavers without orthopaedic problems were included in the study. The forearm and hindlimb were disarticulated from the shoulder and hip joints, respectively. The radius-ulna, tibia, and metacarpal and metatarsal bones were dissected transversely from five anatomical levels. Safe, hazardous, and unsafe corridors were determined in each section. No safe corridor was found in the proximal metaphysis and proximal diaphysis of the radius-ulna. Safe corridors were found on the medial side of the radius-ulna, from the mid-diaphysis to the distal metaphysis. The metacarpal and metatarsal bones showed lateral and medial safe corridors. The tibia provided a continuous medial safe corridor. In conclusion, precise topographic mapping is vital for safe ESF. While anatomically safe corridors are the primary choice for ESF, hazardous corridors are viable alternatives if meticulously utilized. By contrast, unsafe corridors must be strictly avoided to prevent severe iatrogenic trauma. Full article

Background/Objectives: Proton pump inhibitors (PPIs) are widely used for the treatment of acid-related disorders. However, there are concerns that PPI use may be associated with an increased risk of osteoporosis and fractures. This study aimed to investigate the association between PPI use and the risk of osteoporosis and fractures using national data. Methods: Two nested case—control studies using Korean National Health Insurance Service-Health Screening Cohort (514,866 participants, 2002–2019). Study I: 68,719 osteoporosis patients matched 1:1 with 68,719 controls by age, sex, income, region. Study II: 72,456 fracture patients matched 1:1 with 72,456 controls, stratified by fracture site (distal radius [n = 25,882], hip [n = 7753], spine [n = 38,821]). PPI use defined as prescription 1-year preceding index date: current users (≤30 days) and exposed group (31–365 days). Associations were analyzed using propensity score overlap-weighted logistic regression. Results: For osteoporosis, current PPI use showed odds ratio (OR) = 37.4 (95% confidence interval [CI] 33.3–42.1, p < 0.001); exposed group OR = 2.62 (95% CI 2.32–2.96, p < 0.001). Duration-dependent relationship observed: <30 days OR = 8.67, 30–180 days OR = 29.9, ≥180 days OR = 25.0. For fractures, current use associated with distal radius (OR = 37.4, 95% CI 28.8–48.7), hip (OR = 20.3, 95% CI 13.7–30.3), and spine (OR = 29.8, 95% CI 23.7–37.4). However, the exposed group showed no significant associations (distal radius OR = 1.24 p = 0.125; hip OR = 1.34 p = 0.174; spine OR = 1.26 p = 0.057). Conclusions: Current PPI use is strongly associated with increased odds of osteoporosis and fracture in the Asian population, with prominent duration—response relationship. Past PPI exposure showed no significant fracture risk. Healthcare providers should carefully assess bone health risks and consider lowest effective PPI doses. Full article

Supercritical CO₂ gas explosion is an important technique for enhancing permeability in low-permeability coal seams, as it can improve gas drainage efficiency while avoiding the open-flame hazards of conventional explosion and the high water consumption associated with hydraulic fracturing. This study aims to reveal the crack propagation patterns and stress-wave dynamics under different hole configurations. Using LS-DYNA, fracture models were established for three configurations under supercritical CO₂ explosions: single-hole, symmetrical double-hole, and symmetrical double-hole with a control hole. The fracture processes were analyzed to investigate the effective fracture radius of single-hole explosions, the optimal spacing for symmetrical double-hole explosions, and the influence of control holes on crack development and connectivity. The simulation results indicate that the effective fracture radius of a single-hole explosion reaches up to 2.6 m under the modeled conditions. Compared with the single-hole gas explosion case, the symmetrical double-hole configuration with a spacing of 7 m significantly enhances fracture interaction and connectivity, resulting in an approximately 98% increase in the effective damaged area. Permeability enhancement was further quantified by introducing a damage–permeability mapping (k/k₀) based on the simulated damage factor, and the permeability-enhanced zone was evaluated using the criterion of k/k₀ ≥ 2. Full article