Search Results (19,507)

Background and Clinical Significance: Percutaneous vertebroplasty is an effective procedure for patients with osteoporosis and fractures. However, notable side effects may occur. Cement leakage into the vascular system may be incidental, with effects ranging from asymptomatic to life-threatening conditions. The treatment of extravasation of the cement and pulmonary embolism does not have definitive guidelines and requires specific treatment for every patient, ranging from basic anticoagulation to surgical procedures. Cement embolisms without periprocedural complications—such as cardiac perforation or massive pulmonary embolism—are often stable. However, symptomatic presentations with hemodynamic instability can occur. We report a clinically significant case of symptomatic cement pulmonary embolism resulting in shock. Case Presentation: A 68-year-old female patient with osteoporosis and a history of cement vertebroplasty two weeks prior to admission for vertebral compression fracture arrived with a three-day history of left leg swelling and shortness of breath. Vital signs revealed hypotension and the lab tests showed elevated lactate and D-dimer, mild leucocystosis, normal PCT and a threefold increase in CRP. The ultrasound confirmed complete thrombosis of the left external iliac and common femoral vein. The thoraco-abdominal CT demonstrated the extravasation of the cement from vertebroplasty to the inferior vena cava, lumbar veins, coupled with multiple cement structures in the segmental lobar pulmonary arteries. The echocardiography showed preserved right ventricular function. The management included intravenous fluids, anticoagulation and norepinephrine. Conclusions: This case underlines that cement pulmonary embolism following vertebroplasty, while typically undetected, can result in significant hemodynamic compromise even in the absence of right heart failure, potentially mediated by an inflammatory response. Importantly, it highlights the possibility of delayed clinical deterioration, with instability manifesting two weeks post-procedure—distinct from the more commonly observed immediate peri-procedural complications or other stable delayed presentation. Full article

CoCrFeNiMn high entropy alloy (HEA) fabricated via laser-based powder bed fusion (PBF-LB/M) exhibits exceptional mechanical properties, including high strength, better ductility than titanium alloy, and superior corrosion resistance. This study simulates the intergranular fracture behavior of PBF-LB/M CoCrFeNiMn HEA under tensile loading by embedding cohesive elements with damage mechanisms into polycrystalline representative volume elements based on the crystal plasticity finite element method. The simulation results show good agreement with reported experimental stress–strain curves, demonstrating that the crystal plastic constitutive model combined with the cohesive constitutive model can accurately describe both the macroscopic response behavior and fracture failure behavior of the CoCrFeNiMn HEA. Furthermore, this work investigates the mechanical properties of the HEA in different tensile directions, the improvement of anisotropy through columnar-to-equiaxed grain transition, and the effect of texture strength on crack initiation and propagation. The results show that the polycrystalline CoCrFeNiMn HEA exhibits anisotropic mechanical properties: simulated yield strengths (YSs) are 436.9 MPa (in the scanning direction) and 484.7 MPa (in the building direction), tensile strengths (TSs) reach 639 MPa and 702.5 MPa, and elongations (ELs) are 10.6% and 21.8%, respectively. After equiaxed grain formation, the EL in the scanning direction increased from 10.6% to 17.2%, while the EL in the building direction decreased from 21.8% to 20.3%. Concurrently, the anisotropy coefficients of YS, TS, and EL decreased by 1.8%, 2.2%, and 36.1%, respectively. The cracks initiate at stress concentrations and subsequently propagate along grain boundaries until final fracture. Variations in texture strength significantly influence the crack initiation location and propagation path in the CoCrFeNiMn HEA. Full article

Landslides and rockfalls can negatively impact human activities and cause radical changes to the surrounding environment. For example, they can destroy entire buildings and roadway infrastructure, block waterways and create sudden dams, resulting in upstream flooding and increased flood risk downstream. In extreme cases, they can even cause loss of life. External factors such as weathering, vegetation and mechanical stress alterations play a decisive role in their evolution. These actions can reduce strength, which can have an adverse impact on the slope’s ability to withstand failure. For rockfalls, this process also affects fragmentation, creating variations in the size, shape and volume of detached blocks, which influences propagation and impact on the slope. In this context, the Morino-Rendinara landslide is a clear example of rockfall propagation influenced by fragmentation. In this case, fragmentation results from tectonic stresses acting on the materials as well as specific climatic conditions affecting rock mass properties. This study explores how different fragmentation scales influence both velocity and landslide propagation along the slope. Using numerical models, based on lumped mass approach and stochastic analyses, various scenarios of rock material fracturing were examined and their impact on runout was assessed. Different scenarios were defined, varying only the fragmentation degree and different random seed sets at the beginning of simulations, carried out using the Rock-GIS tool. he results suggest that rock masses with high fracturing show reduced cohesion along joints and cracks, which significantly lowers their shear strength and makes them more prone to failure. Increased fragmentation further decreases the bonding between rock blocks, thereby accelerating landslide propagation. Conversely, less fragmented rocks retain higher resistance, which limits the extent of movement. These processes are influenced by uncertainties related to the distribution and impact of different alteration grades, resulting from variable tectonic stresses and/or atmospheric weathering. Therefore, a stochastic distribution model was developed to integrate the results of all simulations and to reconstruct both the landslide propagation and the evolution of its deposits. This study emphasizes the critical role of fragmentation and the volume involved in rockfalls and their runout behaviour. Furthermore, the method provides a framework for enhancing risk assessment in complex geological environments and for developing mitigation strategies, particularly regarding runout distance and block size. Full article

Objectives: Tibial anterior cruciate ligament avulsion fractures (TAFs) are avulsions of the anterior cruciate ligament (ACL) from its insertion at the tibial intercondylar eminence that share the same trauma mechanism as ACL tears. TAFs were initially considered to be a pediatric equivalent to adult ACL ruptures due to the weaker insertion of the ACL on the immature tibial spine. Recent literature suggests that adult TAFs may be more common than previously thought. The incidence, possible concomitant injuries, and other differences between pediatric and adult TAFs remain a topic of ongoing debate in the literature. This systematic review provides a descriptive synthesis of the symptoms, biomechanics, and treatment outcomes of TAFs in pediatric and adult populations. This study highlights notable trends but avoids formal comparisons or meta-analysis due to heterogeneity in the literature. Methods: A systematic review was conducted on human-related studies involving tibial anterior cruciate ligament avulsion fractures, identified in PubMed^®® and EMBASE^®® databases between 2000 and 2024. Studies in English or German were included, while editorials, reviews, experimental studies, and papers with insufficient data were excluded. Data were extracted on patient demographics, trauma mechanisms, fracture classification, diagnostic modalities, treatment approaches, and clinical outcomes. Specific outcome parameters included: incidence and type of postoperative complications, return to sport rate, revision surgeries, hardware removal rates, and duration of follow-up. Due to heterogeneity in reporting, a descriptive synthesis approach was used rather than a meta-analysis. Results: The systematic search identified 3938 publications, with 2707 articles screened after duplicate removal. A total of 56 studies met the inclusion criteria. A total of 677 tibial avulsion fractures (TAF) were analyzed, with 208 (30.4%) pediatric and 469 (69.6%) adult patients. Type III fractures were most common in both groups (pediatric: 63.9%, adult: 63.4%). Concomitant injuries were more frequent in adults (35.6%) than children (8.2%). Arthroscopic surgery was the predominant technique (pediatric: 79.1%, adult: 87.8%). Fixation methods differed: pediatric cases more often used screws (40.5%) and sutures (38.2%), while adults favored sutures (49.7%) and suture anchors (23.1%). Complications were more frequent in pediatric patients (35.1% vs. 17.1%). Conclusions: TAFs show age-related differences in injury patterns and outcomes. Pediatric cases are mostly sports-related, while adult cases are commonly due to road traffic accidents. Concomitant injuries are more frequent in adults, whereas pediatric patients experience higher rates of arthrofibrosis and instability. Adults are more prone to malunion and non-union. These findings support the need for age-specific diagnostic and treatment strategies. Full article

Well integrity is paramount for the safe, environmentally responsible, and economically viable operation of wells throughout their lifecycle, encompassing conventional oil and gas production, unconventional resource extraction (e.g., shale gas and tight oil), and geological storage applications (CO₂, H₂, and natural gas). This review presents a comprehensive synthesis of well integrity challenges, failure mechanisms, monitoring technologies, and management strategies across these operational domains. Key integrity threats—including cement sheath degradation (chemical attack, debonding, cracking, microannuli), casing failures (corrosion, collapse, burst, buckling, fatigue, wear, and connection damage), sustained casing pressure (SCP), and wellhead leaks—are examined in detail. Unique challenges posed by hydraulic fracturing in unconventional wells and emerging risks in CO₂ and hydrogen storage, such as corrosion, carbonation, embrittlement, hydrogen-induced cracking (HIC), and microbial degradation, are also highlighted. The review further explores the evolution of integrity standards (NORSOK, API, ISO), the implementation of Well Integrity Management Systems (WIMS), and the integration of advanced monitoring technologies such as fiber optics, logging tools, and real-time pressure sensing. Particular emphasis is placed on the role of digital technologies—including artificial intelligence, machine learning, and digital twin systems—in enabling predictive maintenance, early failure detection, and lifecycle risk management. The novelty of this review lies in its integrated, cross-domain perspective and its emphasis on digital twin applications for continuous, adaptive well integrity surveillance. It identifies critical knowledge gaps in modeling, materials qualification, and data integration—especially in the context of long-term CO₂ and H₂ storage—and advocates for a proactive, digitally enabled approach to lifecycle well integrity. Full article

Background/Objectives: Radial head arthroplasty (RHA) and open reduction and internal fixation (ORIF) have emerged as predominant methods of surgical management for radial head fractures. The objective of this study was to evaluate national trends in management of radial head fractures among ABOS oral examination candidates and to compare complication rates between RHA and ORIF. Methods: A search of the American Board of Orthopaedic Surgery (ABOS) oral examination database identified radial head fractures treated with RHA or ORIF between 2003 and 2021 in patients 18 years or older. Results: RHA cases increased significantly from 2003–2021 (p < 0.001). Patients undergoing RHA were older (52.4 years vs. 42.9 years, p < 0.001) and predominantly female (60.8% vs. 45.7%, p < 0.001). Medical and surgical complications within 60 days were higher after RHA (2.9% vs. 1.6%, p = 0.012; 24.9% vs. 20.4%, p = 0.001), most commonly stiffness (10.8% vs. 7.1%, p < 0.001), nerve injury (3.3% vs. 2.7%, p = 0.26), and implant failure (3.4% vs. 2.4%, p = 0.064). Non-union or delayed union (0.5% vs. 2.5%, p < 0.001) was significantly higher after ORIF, and fracture (1.1% vs. 0.3%, p = 0.008) was significantly higher after RHA. The highest proportion of RHA to ORIF was performed by surgeons with shoulder and elbow fellowship training (p < 0.001). Conclusions: Among ABOS Candidates, RHA volume surpassed ORIF for radial head fractures in 2010. Surgical complication rates for radial head fractures are high at 60 days follow-up for both procedures. RHA is associated with higher complication rates, especially stiffness; however, similar reoperation and readmission rates suggest that RHA may have been selected for more complex injuries. Full article

Background: Free fatal falls (FFF) represent a distinct form of blunt force trauma (BFT) that is frequently encountered in forensic practice. Distinguishing FFF injuries from other forms of BFT, such as motor vehicle accidents (MVAs), can pose challenges. Despite its growing usage, the role of postmortem computed tomography (PMCT) in diagnosing FFF and its comparison with autopsy remains underexplored. Purpose: This review synthesizes fracture patterns in FFF, examining both extrinsic and intrinsic variables that influence skeletal injuries. It also compares PMCT and autopsy findings to establish a replicable database for forensic analysis. Methods: PubMed and Google Scholar were systematically searched by three independent reviewers. The inclusion criteria required studies to be published in English, report at least 10 cases, focus on fatal falls, and provide precise data on skeletal injuries. Studies lacking detailed descriptions, focusing on survivors, or involving non-free falls were excluded. Data extraction tables facilitated synthesis and analysis. Key Findings: FFF are characterized mainly by axial skeletal fractures, particularly of the chest, skull, and pelvis. A history of intoxication and psychiatric disorders often correlates with the manner of death. Fracture patterns vary by fall height, impact surface, and cause: accidental falls show greater chest and skull involvement, whereas suicidal falls present more pelvic and skull fractures. PMCT detects fractures more frequently than traditional autopsy. Conclusions: Distinct fracture patterns aid in differentiating suicidal from accidental FFF, shaped by extrinsic and intrinsic factors. Given its superior fracture detection capabilities, PMCT should be integrated into forensic protocols for FFF investigations. Full article

Objectives: The indications for femoral endoprosthesis replacement (EPR) use in limb reconstruction have broadened over the last decade. Despite its success, loosening remains the most common reason for failure. No previous system has classified loosening based on the anatomical site in relation to the prosthesis. The aim of this study is to propose a simple reproducible classification system for EPR loosening. Methods: Adult patients that underwent a revision EPR for loosening from 1 January 2023–1 May 2025 were included. Radiographs and computed tomography (CT) images were retrospectively reviewed. The grading was developed on radiographs to classify loosening around EPRs as normal (grade 1), loosening at the shoulder (grade 2), loosening around the shaft of the peg (grade 3), loosening below the tip of the prosthesis (grade 4), associated penetration of prosthesis through the cortex (grade 5), and associated fracture (grade 6). Results: A total of 28 patients were included. The majority of patients were male (n = 17; 61%) with a mean age of 50.6 years (SD 16.1). The average time from the index surgery to diagnosis of loosening was 10.1 years (SD 7.6). The most common pattern of loosening was grade 3 (N = 16; 57.1%). Conclusions: Our classification system proposes an easily adopted way to describe all patterns of loosening around EPRs, potentially guiding revision surgical strategies. Standardizing the approach in evaluating loosening will aid in producing national guidelines for managing this complex complication and may help improve future EPR design. Full article

Grout propagation is a critical aspect of fracture grouting. This study investigated grout propagation at fracture intersections under flowing conditions using a simplified two-dimensional (2D) fracture network. Transparent soil technology was employed to simulate the porous filling material within the fractures. The results showed that the penetration velocity of grout decreased significantly after passing through an intersection, and the velocity in the main fracture was consistently higher than that in the branch fractures. In the unfilled fracture network, the diffusion ratio between branch and main fractures ranged from 0.35 to 0.88, whereas after filling, it ranged from 0.71 to 0.86. For each intersection, the ratio of grout length in the downstream branch to that in the main fracture (RDM) was positively correlated with branch width. This trend was especially evident in unfilled fractures, whereas in filled fractures, the increase in RDM was much less pronounced. Regarding the upstream ratio (RUM), it was consistently lower than RDM. RUM increased with branch width in unfilled fractures but decreased in filled fractures. Additionally, higher fluid velocity amplified these anisotropic propagation behaviors. Based on the simplified filled fracture model, it was concluded that porous filling materials reduce permeability differences between fractures with different aperture widths. Furthermore, increased flow rate intensified the anisotropic diffusion of grout. This study provides valuable insight into the mechanism of anisotropic grout propagation and offers guidance for engineering grouting applications. Full article

Introduction: The elbow is a rare site for bone tumors, and for this reason, the literature provides little data on the epidemiology of metastatic lesions involving the distal humerus, proximal ulna, and radius. Before performing surgery of the metastatic bone, it is first necessary to consider both patients’ and metastatic lesions’ features in order to better choose the best possible treatment. This systematic review aims to collect data on elbow metastases, delineate primary tumors leading to such metastases, guide surgical treatment decisions, and evaluate reconstructive techniques and associated complications. Material and Methods: A systematic literature review was conducted in April 2024, searching the PubMed, MEDLINE, and Cochrane Library databases using specific search terms related to elbow metastases. The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) was followed. Eligible studies reported at least one patient with metastatic bone disease involving the elbow region and specified the undertaken treatment. For studies reporting multiple skeletal sites, only elbow-specific data were extracted. We excluded recurrences of primary elbow tumors. The methodological quality of included studies was assessed with the modified Coleman Methodology Score (mCMS). Results: In total, 28 articles (103 patients) were included. The studies were predominantly case reports (68%), with a mean mCMS of 31. Gender was reported for only 41 patients: 71% were male and 29% female. The mean age at diagnosis of elbow metastatic lesion was 55 years old. Renal cell carcinoma was the most common primary tumor (28%), followed by breast (9%) and lung cancer (6%). The distal humerus was the most frequently affected site (85%). A surgical approach was adopted in 90% of cases, whereas 10% of patients were managed conservatively. Forty-five patients underwent wide tumor resection followed by reconstructive surgery while forty-eight patients received a surgical treatment for either pathological fractures or impending fractures. Conclusions: When treating elbow metastasis, a thorough evaluation of the patient is crucial, considering the patient’s functional status, pain management needs, and overall prognosis; all these features influence the treatment of choice. The selected treatment should aim to provide optimal functional outcomes and minimize complications. For patients with pathological or impending fractures, single or double plate fixation is typically the preferred approach. For patients with severe, symptomatic lesions unresponsive to conservative therapy, resection followed by the implantation of a modular prosthesis usually offers the best clinical and functional outcomes. Full article

Tanshinone IIA (T-IIA), a fat-soluble diterpene quinone extracted from Salvia miltiorrhiza, is widely recognized for its multiple pharmacological properties, including anti-inflammatory, antioxidant, anti-fibrotic, and anti-tumor effects. Recent studies have highlighted its great potential in treating bone metabolic disorders, especially osteoporosis and bone damage repair. Bone health depends on the dynamic balance between osteoblast-mediated bone formation and osteoclast-mediated bone resorption. Disruption of this balance can lead to diseases such as osteoporosis, which is often diagnosed after a fracture, seriously affecting the quality of life and increasing the medical burden. Early identification of high-risk groups and appropriate treatment are essential for preventing fracture recurrence. Studies have shown that T-IIA can promote osteoblast differentiation and inhibit osteoclast activity, targeting key signaling pathways such as NF-κB, PI3K/Akt, and Wnt/β-catenin, all of which are closely related to bone metabolism. T-IIA has a dual role in regulating bone formation and bone resorption, making it a potential drug for the treatment of osteoporosis. In addition, T-IIA has neuroprotective, hepatic, renal, cardiac, and cerebral effects, which enhance its therapeutic effect. Despite the remarkable efficacy of T-IIA, its clinical application is limited due to poor solubility and low bioavailability. Recent advances in drug delivery systems, such as liposome formulations and nanocarriers, have improved their pharmacokinetics, increased absorption rate, and bioavailability. Combination therapy with growth factors or stem cells can further enhance its efficacy. Future studies should focus on optimizing the delivery system of T-IIA and exploring its combined application with other therapeutic strategies to expand its clinical application range. Full article

Compressor blades are subjected to multiaxial loads during operation. Using uniaxial life prediction formulas to predict their fatigue life can result in significant errors. Therefore, by analyzing the loading conditions of the blades, a fatigue life prediction model suitable for compressor blades was developed. This model was established by applying the load of a specific engine type to a notched bar specimen and considering the gradient and strengthening effects. Firstly, the parameters of the SWT model were used as the damage parameters to determine the critical plane location based on the principle of coordinate transformation, and these results were compared with the actual fracture angles. Additionally, the physical mechanisms of multiaxial fatigue crack initiation and propagation were investigated at the microscopic level. Secondly, the non-uniform stress field on the critical plane was obtained using the finite element method. The stress distribution from the critical point to the specimen’s principal axis was extracted and normalized to calculate the equivalent stress gradient factor. Finally, the results of the comprehensive fatigue life prediction model were computed. Comparisons between the calculated results of the proposed model, the SWT model, and the Shang model with the experimental fatigue life showed that the prediction accuracy of the proposed model is higher than that of the SWT model and the Shang Deguang model. Full article

In the context where the surrounding rock of deep coal mine roadways is in a complex mechanical environment of “three highs and one disturbance”, mining disturbances are prone to cause instability and damage to the roadways, and the severe deformation of the south wing main roadway caused by mining disturbances in the 2404 working face of a certain mine in the Jiaoping Mining Area restricts safe production. In order to reduce the deformation and damage of the south wing main roadway affected by long-term dynamic pressure, this study proposes a determination method of key rock strata for top cutting pressure relief and the pressure-relief method along the stress transmission path of the south wing main roadway. It completes the design and field test of the hydraulic fracturing scheme for the hard roof of the 2404 transportation roadway, and evaluates the pressure-relief effect through means such as pressure curves, mine pressure manifestation laws, and borehole observation. The results show that hydraulic fracturing significantly weakens the strength of the roof rock strata, forms through cracks between the pressure-relief holes, reduces the average working resistance of the support by 18% after fracturing, and reduces the average pressure step distance of the roof by 34%. During the mining process, the stress variation range of the coal pillar is small, and there is no obvious deformation or damage to the surrounding rock and support structure of the south wing main roadway. It effectively cuts off the stress transmission path of the hard roof and controls the deformation of the roadway, providing technical support for the control of surrounding rock in deep dynamic pressure roadways. Full article

Chinese coalbed methane (CBM) reservoirs exhibit characteristically low recovery rates due to adsorbed gas dominance and “three-low” properties (low permeability, low pressure, and low saturation). CO₂ thermal drive (CTD) technology addresses this challenge by leveraging dual mechanisms—thermal desorption and displacement to enhance production; however, its effectiveness necessitates uniform fracture networks for temperature field homogeneity—a requirement unmet by conventional long-fracture fracturing. To bridge this gap, a coupled seepage–heat–stress–fracture model was developed, and the temperature field evolution during CTD in coal under non-uniform fracture networks was determined. Integrating multi-cluster fracture propagation with stress barrier and intra-stage stress differential characteristics, a stress-barrier-responsive diverting fracturing technology meeting CTD requirements was established. Results demonstrate that high in situ stress and significant stress differentials induce asymmetric fracture propagation, generating detrimental CO₂ channeling pathways and localized temperature cold islands that drastically reduce CTD efficiency. Further examination of multi-cluster fracture dynamics identifies stress shadow effects and intra-stage stress differentials as primary controlling factors. To overcome these constraints, an innovative fracture network uniformity control technique is proposed, leveraging synergistic interactions between diverting parameters and stress barriers through precise particle size gradation (16–18 mm targeting toe obstruction versus 19–21 mm sealing heel), optimized pumping displacements modulation (6 m³/min enhancing heel efficiency contrasted with 10 m³/min improving toe coverage), and calibrated diverting concentrations (34.6–46.2% ensuring uniform cluster intake). This methodology incorporates dynamic intra-stage adjustments where large-particle/low-rate combinations suppress toe flow in heel-dominant high-stress zones, small-particle/high-rate approaches control heel migration in toe-dominant high-stress zones, and elevated concentrations (57.7–69.2%) activate mid-cluster fractures in central high-stress zones—collectively establishing a tailored framework that facilitates precise flow regulation, enhances thermal conformance, and achieves dual thermal conduction and adsorption displacement objectives for CTD applications. Full article

Objectives: The increasing popularity of electric scooters (E-scooters) has led to a rise in trauma-related injuries, particularly in the craniofacial region. This study aims to compare dentoalveolar trauma (DT) patterns between E-scooter and bicycle accidents in a German urban area to identify differences in injury characteristics, risk factors, and treatment approaches. Materials and Methods: This retrospective study analyzed 178 patients treated for DT following E-scooter (n = 56) or bicycle (n = 122) accidents between January 2022 and December 2022 at a single oral and maxillofacial surgery department in a German urban area. Demographic, clinical, temporal, and therapeutic data were collected and statistically compared. Results: E-scooter patients were significantly younger (mean age: 33.6 vs. 47.0 years, p < 0.001) and predominantly female (85.7% vs. 26.2%, p < 0.001) compared to bicycle patients. E-scooter accidents more frequently occurred at night (69.6%) and on weekends (62.5%) and were significantly associated with alcohol consumption (55.4%) and low helmet use (8.9%). Clinically, E-scooter accidents resulted in more complex dental injuries, including a higher incidence of root fractures (14.3% vs. 0%, p < 0.001), complicated crown fractures (25.0% vs. 9.0%, p = 0.004), and crown-root fractures (32.1% vs. 9.8%, p < 0.001). Mandibular injuries were more prevalent in the E-scooter group, and concomitant facial fractures (excluding alveolar) were also more common (28.6% vs. 19.7%, p = 0.018). Conclusion: E-scooter accidents are associated with a distinct DT pattern involving younger, often alcohol-intoxicated, and helmetless patients, typically presenting with more severe and complex DT-injuries. These findings highlight the urgent need for targeted prevention strategies, legislative measures on helmet use, and clinician awareness of specific trauma profiles linked to E-scooter use. Full article