Joint Fracture Research Articles

Risk Factors for Complications in Reconstructing Congenital Femoral Deficiency.

Congenital femoral deficiency (CFD) is a rare condition, often associated with other skeletal anomalies that make the management more difficult. This study aimed to present the risk factors associated with complications in reconstruction of CFD. This was a retrospective cohort study on patients with CFD who underwent femoral reconstruction between 2002 and 2022, from a single center. The preoperative demographic data, lengthening characteristics, complications, and the predisposing conditions were documented. Thirty-four patients (24 Aitkin A and 10B CFD cases) had 39 lengthening procedures. Twelve cases had simultaneous leg lengthening for associated fibular hemimelia. The mean achieved length was 10.15 ± 3.89 cm, with 72.73 ± 56.19 months follow-up. Although each procedure had 1.8 ± 1.02 complications, 35.8% bowing of regenerate bone and 28.2% fracture; 17.9% hip and 7.7% knee instability were some of the major ones. Hip instability observed in 7 (17.9%) corelated with Aitken type of CFD, preoperative acetabular index, femoral length discrepancy, and achieved length. Bowing in regenerate bone and poor bone consolidation of 15.4% correlated with simultaneous tibial and femoral lengthening (P = 0.018) and higher initial leg-length discrepancy (P = 0.006). The age at reconstruction did not correlate with the number of complications or healing index (P = 0.68, P = 0.15). Five cases received second-time lengthening. Spanning the knee with fixator during lengthening had no notable association with knee instability. Femoral reconstruction in CFD is a challenging but effective task, with joint instability, bowing, fracture, and poor consolidation as potential adverse effects that correlate with simultaneous fibular hemimelia treatment besides the achieved length.

Understanding thermal-mechanical variations and resulting joint integrity of pressure-controlled linear friction welding of thin-steel sheets

Linear friction welding is a solid-state joining technology that bonds materials via friction heating and plastic deformation. This process is being extensively researched for welding metallic sheets with different dimensions; however, it involves difficulties in joining thin cross-sections due to extensive misalignment and unsteady plastic extrusion of softened materials at interfaces. This study introduces novel efforts for joining thin cross-sections through pressure-controlled oscillations and displacements, facilitating localized plastic flow essential for high-strength solid-state bond formation. This method is rare, and the results reveal base metal fractures in tensile-tested welded joints of 2 mm thick S45C steel sheets. The interfacial yielding at specific temperatures is obtained by applying pressure corresponding to the temperature-dependent strength of the material. Accordingly, the welding is attempted using a hydraulic-based clamping system designed to accommodate large sheet lengths while allowing precise control of the interface pressure and temperature to facilitate controlled material plastic discharge. However, the requisite joint evolution tracking remains infeasible due to the intricate weld designs and is instead uncovered through novel numerical investigations. Modeling simultaneous oscillations and forging displacement while maintaining pressure depicted the kinetics of continual interfacial deformation. The transient fluctuations in plastic stress and temperature increments distinguish the stages of forging under different conditions. The computed temperature vs. plastic strain and the measured change in interfacial microstructures from martensite to dynamically recrystallized very fine ferrite with fragmented small cementite explain the lower temperature welding for an increase in applied pressure, enhancing the understanding of linear friction welding of thin steel sections for industrial applications.

The influence of laser-induced tempering on the microstructure and mechanical properties of 1500 MPa martensitic steel friction stir welded joints

A comprehensive comparison illustrates the role of laser technology in altering the macro morphology and microstructure of martensitic steel joints produced by friction stir welding (FSW). In this study, laser-induced tempering (LIT) was introduced to the FSW of 1500 MPa martensitic steel. The mechanism by which LIT enhanced the mechanical properties of the FSW joints was elucidated by comparing joints produced with and without LIT. Experimental findings revealed that LIT effectively eradicated tunnel defects under the same FSW parameters. Even with an increase in travelling speed from 60 mm/min to 120 mm/min, flawless welds were achieved under LIT conditions. At 500 rpm and 60 mm/min, the bottom of the stir zone (SZ) in conventional FSW (C-FSW) joint exhibited a ferrite and martensite dual-phase microstructure. In contrast, the SZ of the LIT-FSW joint had a fully martensitic structure. Moreover, LIT resulted in significant variations in the martensitic hierarchical structure within the SZ. LIT reduced ferrite distribution in the dual-phase zone, caused recrystallized ferrite to appear further from the SZ. The stress concentration in the dual-phase zone attributed to joint fracture. The improvement in the mechanical properties of martensitic steel FSW joints was explained by analyzing the correlation between the stress concentration factor and phase fraction. Additionally, the increase in traveling speed narrowed the dual-phase zone, triggered a constraint effect that led to a maximum ultimate tensile strength (UTS) increase from 986 MPa at 60 mm/min joint to 1142 MPa at 120 mm/min joint.

Effect of adding Ni nanoparticles on the melting characteristics, mechanical properties and intermetallic compound growth of Sn58Bi solder

Purpose This paper aims to investigate the improvement of Sn58Bi solder properties by Ni nanoparticle to provide theoretical support in the field of electronic packaging. Design/methodology/approach In this study, nickel nanoparticles (Ni NPs) were doped into Sn58Bi solder as a reinforcing agent to prepare a composite solder. The wettability of composite solder, melting characteristics of solder alloy, microstructure of joints, mechanical properties and intermetallics growth at the interface were investigated. Findings Test results show that Ni had little substantial effect on the solders alloy melting temperature yet decreased the alloy undercooling. Notably, Ni enhanced solders wettability on Cu substrates. The spreading area increased by 14% at 0.6 wt.% Ni. The Ni refined the microstructure of Sn58Bi solder joints and inhibited the coarsening of the Bi-rich phase in the solder. At the same time, it also led to the production of free intermetallic compounds, increasing growth of the intermetallic compound (IMC) layer. However, upon surpassing 0.6 wt.% Ni, (Cu, Ni)6Sn5 accumulated and formed irregular clumps in the matrix. The grain size of the IMC layer gradually decreased as Ni was added. In shear tests, the fracture of joints occurred mainly inside the solder matrix. Sn58Bi-0.6Ni joints displayed a 40% rise in shear strength and a 25% rise in Vickers hardness. In addition, the appearance of dimples at the fracture indicated the improved flexibility of joints. Originality/value In this paper, Ni nanoparticle with different contents were added to Sn58Bi solder to prepare a composite solder, and the properties of the composite solder were investigated from different perspectives.

Study on the tensile failure mechanisms of CFRP‐Al flat‐joggle‐flat bonded joints

AbstractThis paper focuses on CFRP‐Al bonded joints, experimentally investigating the effects of joint geometries, different types of adhesives, and overlap lengths on the mechanical properties of bonded joints. Digital Image Correlation (DIC) technology was used to monitor the entire tensile processes, and the deformations and fracture processes of the bonded joints were captured. The strain evolution processes of the joints were obtained through analysis, and quantitative analyses of the joint fracture surfaces were conducted. The results indicate that the special geometric shape of the Flat‐Joggle‐Flat (FJF) bonded joint reduce secondary bending effects. Additionally, the joggle section participates in load transfer, significantly enhancing the joint's mechanical performance and altering its failure mode. Joints using ductile adhesives exhibit higher tensile mechanical properties compared to those using brittle adhesives. Compared to the bearing capacity of single‐lap bonded joints with the same overlap length and adhesive, the mechanical performance improvement of FJF bonded joints using ductile adhesives is less pronounced than that of FJF bonded joints using brittle adhesives. Increasing the overlap length enhances the mechanical properties of bonded joints. This study is expected to provide a reference for the engineering application of FJF bonded joints.Highlights FJF joints have higher bearing capacities compared to single lap joints. Ductile adhesives can effectively increase the bearing capacities of joints. Increasing the overlap length can improve the bearing capacities of joints. The end and middle of the FJF joints jointly bear the load effect. The failure modes of FJF joints are different from that of single lap joints.

High-strength stainless steel joints achieved by co-regulation mechanism of phosphide dispersed distribution and γ-phase generation

A novel iron-based filler FeCr18Ni10Si6P6 was designed to address the inherent limitations of joint strength reduction caused by the formation of the continuous brittle phase in the diffusion affected zone (DAZ) during traditional iron-based filler joints. The influence of process parameters on the microstructure evolution and mechanical properties of the joints was subjected to a comprehensive examination. The results indicated that the diffusion of Cr would result in the formation of α-phase in DAZ of the joints, which predominantly solidified most of the P atoms. This ultimately led to the precipitation of phosphide in the form of fine needles, enhancing the strength of the joints and altering the joint fracture region from DAZ to athermal solidified zone (ASZ). The joint strength peaked at 177 MPa when brazed at 1120 °C for 15 min, which is 2.6 times higher than that of traditional iron-based filler metals used in bonding. This filler metal presents a novel approach to the low-cost and high-quality joining of stainless steel.

Fatigue fracture mechanism and life prediction of steel-aluminium clinched joints under different stress ratios

Vehicle bodies are subject to complex random loads during travelling, making it imperative to investigate the effects of different stress ratios on the body joining structure. To investigate the fatigue performance of steel-aluminium clinched joints under different stress ratios, fatigue experiments were conducted on these joints subjected to different load levels at stress ratios of -0.4, 0.1, and 0.4. The fracture mechanism of steel-aluminium clinched joints under different stress ratios was investigated through analysis of the joint's fracture morphology and the composition of abrasive chips using Scanning Electron Microscope and Energy Dispersive Spectroscopy. A fatigue life prediction model for steel-aluminium clinched joints was developed by employing the modified Paris formulation of the Wallker equation. The results indicate that joint failure can be classified into three main forms: lower sheet fracture, upper sheet pull-off accompanied by lower sheet fracture and reaching infinite life (2 million times). The lower sheet of a fatigue failure specimen in a steel-aluminium clinched joint exhibited a novel form of fretting damage known as lower sheet inter-plate fretting wear. Furthermore, the application of Walker's improved Paris formula proved to be highly effective in accurately predicting the fatigue life of steel-aluminium clinched joints under different stress ratios, with the predicted results demonstrating excellent agreement with experimental findings.

Construction and Application Effect Analysis of Orthopedic Pain Care Ward under Multi-Disciplinary Cooperation Model

Aims/Background A multidisciplinary team (MDT) approach is a nurse-led pain management method that involves collaboration with staff from other departments. The purpose of this paper was to discuss the construction and application effect of a pain care ward in orthopedics utilizing the MDT approach. Methods A retrospective analysis of case data was conducted, selecting 90 patients with hip joint fractures who underwent hip replacement arthroplasty (HRA) at our hospital between February 2021 and February 2024. The patients were divided into two groups based on the nursing methods: a control group (n = 43), which received a conventional analgesic management program, and an intervention group (n = 47), which received the same conventional analgesic management program along with the implementation of an orthopedic pain care ward under the MDT approach. The study compared the pain knowledge and attitudes of the responsible nurses in both groups through questionnaires. Additionally, the accuracy of pain assessments and the awareness rates of patients’ pain-related health education were evaluated and compared between the two groups. Furthermore, the effectiveness of pain intervention, range of motion (ROM), and Hospital for Special Surgery (HSS) scores before and after the intervention were analyzed. The incidence of complications and overall nursing satisfaction were also compared between the two groups. Results The general knowledge, pain assessment, drug analgesia, comprehensive application, and total scores of nurses in the intervention group were significantly higher than those in the control group (p < 0.05). The accuracy rate of nurses’ pain assessments and the awareness rate of patients’ pain health education in the intervention group were 91.49% and 93.62%, respectively, both significantly higher than the 72.09% and 79.07% observed in the control group (p < 0.05). The total effective rate of pain intervention in the intervention group was 74.47%, significantly higher than the 53.49% in the control group (p < 0.05). After the intervention, both the ROM and HSS scores in the intervention group were significantly higher than those in the control group (p < 0.05). The overall incidence of complications in the intervention group was 6.38%, significantly lower than the 20.93% in the control group (p < 0.05). Finally, the total satisfaction rate with nursing care in the intervention group was 91.49%, significantly higher than the 74.42% in the control group (p < 0.05). Conclusion The construction and application of an MDT pain care ward can effectively enhance the accuracy of nurses’ pain assessments, increase patients’ awareness of pain-related health education, and improve the efficiency of pain interventions. Additionally, it can lead to better joint mobility and improved hip function, promoting the sustainable development of the pain care ward. These improvements contribute to higher patient satisfaction and enrich the quality of nursing services.

On the investigation of microstructure and mechanical properties of the AlCoCrFeNi2.1/316 L dissimilar spot-welded joint

This study receives a free-defect spot-welded joint, using the base metal of AlCoCrFeNi2.1/316 L, for the first time, by a resistance spot welding technique. Electron backscatter diffraction, X-ray diffraction, and scanning electron microscopy were used to analyze the microstructure of the nugget and heat-affected zone of the spot-welded joint. Mechanical experiments were conducted to gain mechanical properties such as micro-hardness and shear tensile strength. The nugget on the side of 316 L and AlCoCrFeNi2.1 is not fully symmetrical, and the nugget offset is observed on the AlCoCrFeNi2.1 side owing to dissimilar thermo-physical properties. Thermodynamic calculation and XRD diffraction analysis confirm that both austenite and (Fe, Ni) phases are existent in the nugget zone. Eventually, under a shear load, an interface fracture of the spot-welded joint was observed and the fracture morphology was examined. This work could serve as an initial basis for further research on high entropy alloy resistance spot welding.

Deformation behavior study of SAC305 solder joints under shear and tensile loading by crystal plasticity finite element method

Micro solder joints experience various loads during operation, and the failure of a single micro solder joint can impact the overall reliability of the entire microsystem. This study utilized the Crystal Plasticity Finite Element Method (CPFEM) to create a polycrystalline model that accurately represents the shape of solder joints. By calibrating the crystal plasticity characteristics of SAC305 material solder joints using macroscopic stress-strain curves, the model successfully simulates the deformation mechanisms of micro-solder joints under both tensile and shear loads. This paper highlights that equivalent plastic strain serves as a key indicator of solder joint fracture behavior, revealing that strain components have varying effects on cracking: shear strain was found to cause crack initiation, while normal strain was found to promote crack extension. Moreover, Grain boundary features and orientation lead to uneven plastic strain by affecting the slip system and the Schmidt factor, especially small Schmidt factor grains at triple grain boundary intersections are more susceptible to crack initiation. Additionally, the study found that solder joints exhibit more pronounced mechanical responses under tensile loading compared to shear loading. These insights offer valuable guidance for the design and manufacturing of micro-solder joints.

Unraveling the therapeutic potential of Astilbe rivularis Buch.-Ham. ex D. Don in attenuation of diabetic neuropathy in laboratory rats

Ethnopharmacological relevanceAstilbe rivularis Buch.-Ham. ex D. Don is a rare medicinal plant, traditionally employed for treating several disorders. The juice, decoction or powder of the roots, rhizomes, leaves and even the entire plant, are used for managing peptic ulcer, diarrhoea, jaundice, sprains and muscular swellings, bone fracture and dislocation of joints, postpartum bleeding and other menstrual disorders. These conventional medicinal uses make Astilbe rivularis a promising candidate for further research. Aim of the studyThis study was designed to explore the neuroprotective potential of hydroethanolic extract of Astilbe rivularis (ARHE) in diabetic neuropathy (DN) in rats. Materials and methodsGC-MS analysis was used to identify the phytoconstituents present in the plant extract. DN was induced by administration of STZ (55 mg/kg, i.p.), 15 min after NAD (230 mg/kg, i.p.) injection. The rats with fasting blood glucose (FBG) level >250 mg/dl were included in the study. DN was assessed by estimating the level of FBG, lipid profile, and invitro and invivo oxidative stress parameters. Additionally, behavioural parameters like, mechanical hyperalgesia, hot and cold allodynia were estimated to assess diabetic neuropathy. Furthermore, the level of antioxidant enzymes like SOD, GSH, and TBARS in sciatic nerve and inflammatory markers like, TGF-β and IL-6 were measured. ResultsAltogether, 30 phytoconstituents were identified including heptafluorobutyric acid, hexadecanoic acid, and beta-sitosterol depicting antioxidant, antidiabetic, and anticancer properties, respectively. Administration of different doses (100, 200, and 400 mg/kg) of ARHE to diabetic rats attenuated elevated blood glucose level and restored lipid profile, body weight, food and water intake, and antioxidant level. Moreover, elevated level of inflammatory markers like, TGF-β and IL-6 was also found to be attenuated in sciatic nerve. Furthermore, ARHE attenuated the pain response assessed by mechanical hyperalgesia and hot and cold allodynia in diabetic neuropathy rats. ARHE also showed inhibitory activity on ALR enzyme and erythrocyte sorbitol accumulation, and ameliorated oxidative stress. Histopathological study indicated improvement in the architecture of sciatic nerve tissue in diabetic neuropathy rats with the treatment of ARHE. ConclusionsConclusively, hydroethanolic extract of Astilbe rivularis exhibited neuroprotective potential and ameliorated diabetic neuropathy in rats.

Total knee arthroplasty combined with simultaneous open reduction and internal fixation in the treatment of knee osteoarthritis with patellar fracture: a case report and review of the literature

BackgroundPatients with severe knee osteoarthritis combined with patellar fracture are rare, and it is unclear whether single-stage surgery affects the enhanced recovery after surgery.Case presentationThis case report describes two patients of Han nationality. A 69-year-old male patient was previously diagnosed with severe knee osteoarthritis of the left knee joint and was treated conservatively with long-term oral nonsteroidal antiinflammatory drugs and intraarticular injection of sodium hyaluronate. He was hospitalized for acute left knee injury owing to a fall from a height. He was diagnosed with knee osteoarthritis of the left knee joint and patellar fracture. Another 74-year-old female patient was previously diagnosed with severe knee osteoarthritis, long-term oral nonsteroidal antiinflammatory drugs and topical Chinese medicine to relieve the pain. A month ago, she fell down the stairs and fractured the patella in her left knee, she was diagnosed with severe left knee osteoarthritis combined with an old left patella fracture. Both patients were successfully treated by single-stage primary total knee arthroplasty and fixation of the patellar fracture. They both carried out early functional exercise normally and successfully achieved enhanced recovery.ConclusionSuccessful single stage total knee replacement with patella management can not only reduce the number of operations, but also enable patients to achieve rapid postoperative recovery. However, single stage may increase the risk of local surgical complications. Therefore, for most patients, especially those with low risk of anesthesia related complications, standard of treatment remains first fixing the patellar fracture and when the fracture is healed proceed with the total knee arthroplasty.

Microstructure evolution and mechanical properties of diffusion bonding CoCrCuFeNi high entropy alloy to Inconel 600 alloy

In this study, the CoCrCuFeNi high entropy alloy was diffusion bonded with the Inconel 600 superalloy at bonding temperatures ranging from 950 to1100 °C for a bonding time of 2h under a pressure of 20 MPa in a vacuum. The microstructure and mechanical properties of the diffusion bonded joints were investigated. The diffusion zone of the welded joint contains of two distinct zones: a coarse grain zone (on the Inconel 600 superalloy side) and the diffusion interface layer. The blocks Cr23C6 phase and Cu-rich phase were formed in the diffusion interface layer at 950 °C. As the bonding temperature increased, the Cr23C6 gradually disappeared and the blocks Cu-rich phase transformed into nano Cu-rich precipitate in the diffusion interlayer at 1100 °C. The hardness of the interface layer was significantly higher than that of the base metal at all temperature. When the bonding temperature increased from 950 °C to 1100 °C, the ultimate tensile strength of the welded joints increased from 521 MPa to 558 MPa, and the elongation increased from 10.3 % to 31.2%, respectively. The ultimate tensile strength reached 96 % and 82 % than that of the CoCrCuFeNi HEA and Inconel 600 base metal, and the elongation is comparable to that of the base metals. All the welded joint fracture near the diffusion interface layer. As the bonding temperature increased, the fracture mode of the joint transformed brittle to ductile. At an elevated temperature of 300 °C, the ultimate tensile strength and elongation of the welded joint are 325 MPa and 9.8 %, respectively. The welded joint exhibits a mixed fracture mode of ductile and cleavage fractures.

Rock Slope Instability Mechanism Induced by Repeated Mining in Mountain Mining Areas

When mineral resources are extracted using underground mining methods in hilly regions, landslides or slope failures can be induced frequently. In this study, slope collapse disasters in mountain mining areas were analyzed. The model test and numerical simulation of the slope impacted by repeated mining were carried out. The crack evolution and failure process were analyzed to reveal the instability mechanism. The results show that the rock mass would topple to the inside of the slope first, when the subsidence of overlying rock was induced by the mining of the upper coal seam. When repeated mining was performed in the lower coal seam, the mining induced macro-cracks that could connect with natural fissures, inducing the outward displacement of the slope. Then, the rock mass at the foot of the slope has to bear the upper load, which is also squeezed out by the collapsed rock mass, forming the potential slip zone. Finally, the instability is caused by the shear slip of the slope toe rock mass. Therefore, the instability evolution of the slope under underground repeated mining disturbance can be divided into four stages as follows: roof caving and overlaying rock subsidence, joint rock toppling, fracture penetration, and slope toe shearing and slope slipping.

A clinical study on the effect of axillary approach in the treatment of Ideberg type II scapular glenoid fractures

BackgroundDue to its deep position and complex surrounding anatomy, the scapular glenoid fracture was relatively difficult to deal with especially in cases of severe fracture displacement. Improper treatment may lead to failure of internal fixation and poor fracture reduction, severely affecting the function of the shoulder joint. Inferior scapular glenoid fracture was Ideberg type II fracture, and posterior approach was commonly used to deal with inferior scapular glenoid fracture. However, there are shortcomings of above surgical approach for inferior scapular glenoid fracture, such as insufficient exposure of the operative field, significant trauma, and limited screw fixation direction. This study adopts the axillary approach for surgery, which has certain advantages.MethodsThe clinical data of 13 patients with Ideberg type II scapular glenoid fractures treated from December 2018 to January 2024 were retrospectively analyzed. There were 8 males and 5 females, with an age range of 19 to 58 years and an average age of 38 years. The causes of injury were falls from heights in 7 cases and car accidents in 6 cases. There were 5 cases on the left side and 8 cases on the right side. The time from injury to surgery was 2 to 11 days, with an average of 5.5 days. All cases underwent open reduction and internal fixation through the axillary approach. Postoperative X-ray and CT three-dimensional reconstruction were performed on the next day to evaluate the fracture reduction and the position of internal fixation. During the follow-up period, follow-up examinations were performed every two months in the first half of the year and every three months in the second half. CT scans were performed during the examinations to assess the glenohumeral joint congruence, fracture healing, and position of internal fixation. The shoulder joint function was evaluated at 6 months postoperatively according to the Constant-Murley value score.ResultsThe patients all achieved primary wound healing after surgery, without any complications such as infection or nerve injury. Re-examination on the second day after operation, all fractures obtained excellent reduction, and the internal fixation was in excellent position, and no screw was found to enter the joint cavity. All patients in this group were followed up for 6 to 25 months, with an average follow-up time of 11.7 months. All fractures were bony unioned, and the healing time ranged from 4 to 6 months, with an average healing time of 4.8 months. At 6-month follow-up, according to the Constant-Murley score, 11 cases were excellent and 2 case was good.ConclusionOpen reduction and internal fixation through the axillary approach is an feasible and safe surgical method for the treatment in scapular Ideberg type II glenoid fractures with less stripping of soft tissue, minimal surgical trauma, and the incision is concealed and beautiful. It can provide a strong internal fixation for fractures, so patients can perform functional exercise early after operation, and the clinical results is satisfactory.

Influence of surface pretreatment of steel substrate on the interfacial microstructure and tensile properties of laser Al/steel joints

The influence of surface-pretreatments, viz., subtractive manufactured (SMed), additively manufactured (AMed), and untreated (UTed) steel substrates on dissimilar laser aluminum (Al)/steel joints were comparatively investigated, for the first time, in terms of the interfacial microstructure and mechanical properties. Compared to the UTed joints, the interfacial microstructure of SMed joints remained unchanged with both composing of Fe-Al-Si and Fe-Al IMCs, but the joint fracture energy increased from 1.89 kJ to 2.39 kJ. Differently, the interfacial microstructure changed to a composite structure consisting of a high entropy alloys (HEAs) skeleton and reaction regions, and the joint fracture energy further increased to 4.38 kJ in the case of AMed joints. The mechanisms of the altered interfacial microstructure and tensile properties were also investigated.

Procedural Sedation and Analgesia in an Australian Emergency Department: Results of the First 3 Months of a Procedural Sedation Registry

Background: Procedural sedation and analgesia (PSA) is commonly performed in emergency departments (EDs) to reduce anxiety, discomfort, or pain during a procedure. The primary goal of PSA is to produce a state of relaxation and drowsiness without eliminating the patient’s protective reflexes. Despite the discovery of new techniques and medications to deliver PSA, there is a paucity of research evaluating PSA in EDs over the last decade. We aim to describe the current practice of PSA in an Australian tertiary mixed ED with 75,000 presentations per year. Methods: A retrospective study of the initial 3 months of a PSA registry, which was part of the Tasmanian Emergency Care Outcomes Registry, was analyzed; Results: All told, 80 consecutive cases were entered over a 3-month period, with pediatric patients (<14 years old) making up 35% of all cases. Joint reductions (17, 39%) and fracture reductions (13, 29%) were the most common indications for the adult population, whilst fracture reductions (9, 36%), laceration repairs (7, 28%), and other distressing procedures (7, 28%) were the most common indications in the pediatric cohort. Pharmacological approaches also differed between groups, with ketamine (25, 92%) preferred in the pediatric cohort whilst the combination of propofol and fentanyl (22, 42%) was preferred in the adult cohort. No adverse events were recorded in the pediatric cohort whilst 6 (8%) minor events occurred in the adult population, with no severe events occurring for either cohort. PSA also occurred more frequently at 0900–1000 and the incidence was reduced between 0000 and 0800. Conclusions: PSA is commonly performed in our tertiary mixed ED and is both safe and effective, with non-severe complication rates similar to those in the reported literature. Severe complications are rare and therefore a larger cohort will be required to assess this aspect. The approach to ED PSA is also different between pediatric and adult populations and therefore research needs to differentiate both populations.

F-type forceps for assisted reduction in femoral shaft fractures surgery

To explore clinical efficacy of F-type forceps for assisted reduction in femoral shaft fracture reduction. Forty-five patients with femoral shaft fracture treated with intramedullary nail and internal fixation from January 2019 to December 2021 were retrospectively analyzed and divided into two groups according to different reduction methods. In observation group, there were 21 patients, included 15 males and 6 females, aged from 27 to 92 years old with an average of (53.38±18.81) years old;9 patients on the left side, 12 patients on the right side;7 patients were type A, 8 patients were type B and 6 patients were type C according to AO fracture classification;the time from injury to operation ranged from 7 to 13 days with an average of (4.62±3.34) days;reduction was assisted by F-shaped forceps. In control group, there were 24 patients, including 17 males and 7 females, aged from 20 to 92 years old with an average of (51.96±20.43) years old;12 patients on the left side, 12 patients on the right side;11 patients were type A, 8 patients were type B and 5 patients were type C according to AO fracture classification;the time from injury to operation ranged from 2 to 13 days with an average of (6.29±3.04) days;traditional reset mode was adopted. Operative time, intraoperative blood loss, intraoperative fluoroscopy times, intraoperative open reduction ratio, clinical healing time of fracture, postoperative complications, hospital stay, hospital cost and Lysholm score of knee joint at 6 and 12 months after surgery were compared between two groups to evaluate clinical effect. All patients were followed up for 12 to 24 months with an average of (16.60±3.45) months. In observation group, operative time, intraoperative blood loss, intraoperative fluoroscopy times, open reduction cases, and clinical healing time of fractures were (58.19±7.93) min, (88.10±44.45) ml, (25.29±5.54) times, 0 case, (4.76±0.77) months, respectively;while in control group was (79.33±22.94) min, (222.92±144.45) ml, (47.46±26.25) times, 5 cases, (7.13±1.80) months, and the difference between two groups were statistically significant (P<0.05). There were no significant difference in postoperative complications, length of stay and hospitalization cost between two groups (P>0.05). At 6 months after surgery, Lysholm score of knee joint in observation group (88.62±4.48) was better than that in control group (79.21±8.91) (F=21.948, P=0.000). There were no significant difference in support use, pain and squat score between two groups (P>0.05). At 12 months after surgery, Lysholm scores of stair climbing and pain in observation group were (9.62±1.20) and (19.76±1.92), which were better than those in control group (7.83±2.04) and (21.88±2.88) (P<0.05). There were no significant difference in scores and total scores of other items between two groups (P>0.05). Compared with traditional reduction method, F-type forceps instrument could shorten operation time, reduce intraoperative blood loss, reduce intraoperative fluoroscopy times, accelerate clinical healing of fracture, and promote earlier functional recovery of knee joint.

Experimental study on the residual strength of butt adhesive joints subjected to systematic creep damage

AbstractUsing adhesively bonded joints is an effective strategy for achieving lightweight designs. However, understanding the long‐term performance of these bonded joints remains a critical concern. Creep is a time‐dependent phenomenon induced by sustained mechanical loads, which can lead to viscous strain in adhesive materials. This strain has the potential to cause cracking in bonded structures over time. This study aims to investigate the creep and post‐creep behaviors of adhesively bonded aluminum joints, focusing on two crucial parameters: creep load level and creep duration. Butt adhesive joint (BAJ) specimens were fabricated and exposed to varying creep loads and times. Subsequently, quasi‐static tensile tests were conducted to assess the residual mechanical properties. The results indicated that higher creep loads resulted in increased creep deformations at constant creep durations. Furthermore, a downward trend was observed in the residual tensile mechanical properties of BAJ specimens following creep. Specifically, higher creep load levels and longer times led to more pronounced reductions in joint strength, strain, and stiffness. These reductions in joint mechanical properties were corroborated through joint fracture surface analysis. Additionally, mathematical models were developed using response surface methodology (RSM) to predict the experimental joint residual mechanical properties under different creep loads and times.Highlights Investigation of creep and post‐creep behaviors in adhesive joints. Higher creep load levels result in greater joint permanent deformations. Impact of higher creep load levels and durations on joint failure strength. Decreasing in the joint deformability and stiffness after creep.

Effect of an Ultrasonic Vibration on the Microstructure and Properties of Al Alloy/Steel Laser Welding-Brazing Joints

This study analyzes the influence of different ultrasonic amplitudes on the microstructure composition, microhardness, tensile strength, and corrosion resistance of Al alloy/steel laser welding-brazing joints assisted by ultrasonic vibration. The application of ultrasonic vibration did not change the microstructure composition of the joints but refined them. The joints were all composed of θ-Fe(Al, Si)3 and τ5-Al7.2Fe1.8Si formed at the interface reaction zone, as well as an α-Al solid solution and Al-Si eutectic phase generated in the weld seam zone. Meanwhile, the thickness of the IMCs at the interface decreased with an increase in the ultrasonic amplitude. When the ultrasonic amplitude was 8 μm, the IMCs thickness was a minimum of 1.62 μm. In this condition, the reduction of the IMCs thickness and the refined grain of joints made the microhardness and tensile strength reach the maximum. The fracture of joints with ultrasonic amplitudes of 0 and 4.8 μm began at the weld seam and extended to the interface reaction zone at the steel side, while the fracture of joints was located in the heat-affected zone (HAZ) of the Al alloy side when the ultrasonic amplitude was 8.0 and 11.2 μm. The fracture mode of the former presented a typical mixed fracture with cleavage steps and tearing edges, and that of the latter showed ductile fracture with uniform and fine ductile dimples. The corrosion resistance of the joints was improved by adding ultrasonic vibration. When the ultrasonic amplitude was 8 μm, its corrosion resistance was optimum; it was ascribed to a dense oxide film formed on the surface of the metal under the action of ultrasonic vibration.