Annals of Biomedical Engineering最新文献

Purpose: The biofidelity of anthropomorphic test devices directly affects the evaluation of safety performance of child restraint systems. The purpose is to enhance the biofidelity of Q3 child dummy by chest structure reconstruction for the accurate prediction of the child injuries during a frontal crash.

Methods: The finite element model of Q3 child dummy restrained in impact shield child restraint systems was validated through a frontal sled test. Based on the validated sled test simulation models, the comparative biofidelity analyses between Q3 model and PIPER 3-year-old human model were conducted by the quantitative kinematic and biomechanical analyses. The internal chest structure difference between Q3 and PIPER 3-year-old human model is discussed, and the absence of the heart, lungs, and great vessels in the Q3 dummy leads to the low biofidelity; therefore, the chest structure and cardiopulmonary model of Q3 dummy were reconstructed to enhance the biofidelity.

Results: In comparison to the original Q3 model, the chest deflection, head forward displacement, and neck bending angle of the reconstructed Q3 model increased by 38.5, 2.2, and 17%, respectively, and the upward displacement of the hip decreased by 49%. The head swing degree of the reconstructed Q3 model is dramatically reduced during the rebound process, and the injury assessment criteria of the head, chest, and pelvis can reach more than 95% of the level of the PIPER 3-year-old human model.

Conclusions: This study shows that the chest reconstruction can significantly improve the biofidelity of the Q3 dummy, and future study is recommended to optimize the spinal structures of the Q3 model for further enhancement of biofidelity.

Purpose: Cycling is a leading cause of youth sports-related head injury in the U.S. Although youth bicycle helmets sold in the U.S. comply with safety standards limiting head linear acceleration, there needs to be more information on relative differences in protection between helmets that pass. Additionally, studies have yet to look at quantifying youth bicycle helmet performance with respect to their design.

Methods: Twenty-one youth bicycle helmet models were subjected to oblique impacts at three locations and two impact speeds where peak linear acceleration (PLA) and peak rotational acceleration (PRA) were quantified. Design features were characterized, including expanded polystyrene (EPS) thickness and presence of shell protrusions. A linear mixed model was used to quantify the effects of design features on PLA and PRA.

Results: The youth bicycle helmet models evaluated produced wide ranges in kinematics across all configurations. PLA averaged 95.9 ± 26.1 g at 3.1 m/s and 170.1 ± 43.5 g at 5.2 m/s, while PRA averaged 3150 ± 1275 rad/s² at 3.1 m/s and 4990 ± 1977 rad/s² at 5.2 m/s. Impact location, impact speed, and EPS thickness had strong effects on PLA and PRA, whereas shell protrusions only had strong effects on PLA.

Conclusion: Youth bicycle helmets with thicker EPS, thinner shells, and shell protrusions at impact locations improved the linear and rotational kinematic measures. Limitations include the small sample size and the impacts analyzed not representing all possible real-world scenarios.

In recent years, notable advancements have been achieved in the domain of tissue engineering and regenerative medicine, presenting auspicious remedies for the management of diverse injuries and ailments. The management of bone injuries necessitates the implementation of a customized approach depending upon the specific nature of the injury. Tissue engineering plays a major role in the treatment of such bone injuries. One key aspect of tissue engineering is the development of scaffolds that can provide structural support and guide the growth of new tissue. The scaffold should possess mechanical properties that enable it to withstand weight-bearing stresses, resembling the strength and durability of real bone. This review explores the latest research findings from pioneering research papers in tissue engineering, focusing on scaffolds, bioceramics, and the various technique for the development of scaffolds with a focus on 3D printing. By examining and synthesizing key studies in these areas, this review aims to provide insights into the current state of knowledge, identify research gaps, and contribute to the advancement of tissue engineering approaches for regenerative medicine applications.

Purpose: To identify the mechanical and morphological regional changes of articular cartilage on the first metacarpal and trapezium and their association with attenuation of the volar ligament complex (VLC) during trapeziometacarpal (TMC) osteoarthritis (OA) progression.

Methods: Twenty-four fresh-frozen female cadaveric TMCs were separated into (1) younger healthy/early-stage osteoarthritic, (2) elder healthy/early-stage osteoarthritic, and (3) advanced-stage osteoarthritic groups based on age and Eaton-Littler grading. Metacarpal and trapezium surfaces were split into six regions. Microindentation testing was performed to characterize the biphasic properties of each region. Light imaging, scanning electron microscopy/energy dispersive spectroscopy, and magnetic resonance imaging were performed to assess cartilage integrity and identify wear patterns.

Results: The volar ulnar region of the metacarpal, along with the volar central and volar ulnar regions of the trapezium, had a higher equilibrium modulus in the advanced-stage OA specimens. SEM/EDS revealed these regions to be fully eburnated in most cases. MRI revealed eburnation, as well as the degeneration and/or detachment of the beak ligament portion of the VLC. In the advanced-stage OA TMCs, an increased equilibrium modulus in the volar portion of the trapezium correlates to attenuated VLC stiffness from our previous study.

Conclusion: A regional pattern in articular cartilage degeneration, including changes in biphasic properties evidenced by an increased equilibrium modulus, during TMC OA progression is evident with the most significant changes occurring in the volar ulnar region of the metacarpal and volar central and volar ulnar regions of the trapezium. These changes in articular cartilage can be correlated to an attenuated VLC.

Purpose: Vascular flow phantoms are an invaluable tool for in vitro and in silico studies, but their design and fabrication processes are often not reported. In this study, a framework is introduced to design and fabricate 3D printable high-fidelity cohort-based averaged abdominal aortic aneurysm (AAA) phantoms.

Methods: AAA geometries of 50 patients were segmented from preoperative computed tomography angiography scans. The segmented geometries and center lumen lines (CLL) were used in an in-house developed algorithm to average the CLL coordinates and corresponding diameters over the entire cohort. The reconstructed averaged anatomy was 3D printed as a thin-walled flow phantom with Formlabs Flexible 80A resin. The acoustic properties of the resin were characterized and the feasibility of flow field quantification inside the phantom with ultrasound particle imaging velocimetry (echoPIV) was investigated.

Results: Comparison between patient-specific models generated by our method and their corresponding reference segmentations, for ten patients, showed a mean Sørensen-Dice similarity coefficient of 0.916 ± 0.21 and the largest distances (5-10% of the lumen diameter) were found at the aneurysmal sac. The Flexible 80A resin had an average speed of sound of 1785 m/s, attenuation of 7.8 dB/mm and density of 1130 kg/m³. Volumetric flow profiles obtained with echoPIV in the suprarenal artery (i.e. phantom inlet) matched the flow sensor data.

Conclusion: The reported framework was used to make an averaged, cohort-based AAA model, which showed a good match with its reference model. A 3D printed, thin-walled phantom was made based on this model and the feasibility of flow field quantification inside the phantom was shown.

Purpose: This study aimed to investigate the effects of different arterial cannula models on hemodynamic performance and blood damage associated with femoral artery cannulation in venoarterial extracorporeal membrane oxygenation (VA-ECMO).

Methods: Eleven cannula models were constructed and processed to study their hydrodynamic performance and hemolysis in a circulated loop. All circulation environments were analyzed using computational fluid dynamics to investigate hemodynamic changes under different ECMO flow conditions.

Results: The multiple side-hole cannula structure effectively reduces the cannula pressure drop and ECMO blood pumping rate compared to cannula without side holes, thereby reducing overall blood damage in the ECMO circulation. The cannula pressure drop decreased with increasing number of side holes and became the lowest in the four and six-side-hole cannula models. A gradual increase in the number of cannula side holes improved the lower limb blood diversion ratio of ECMO, and this increase was less pronounced with a higher number of side holes. Adding a lower-extremity diversion hole can further increase the level of lower-extremity perfusion. The overall hemolytic damage in the ECMO circuit decreased gradually with an increasing number of cannula-side holes, reaching to the lowest levels in the 4 and 6-side hole cannulation models. The lower extremity blood flow rate reduced after the cannula was implanted into the vessel, forming an area of high blood retention and platelet activation in the cannula vicinity, with a greater risk of thrombosis.

Conclusion: Cannula structure plays an important role in determining ECMO limb perfusion distribution, hemolysis, and thrombosis risk. A modest increase in the number of cannula side holes and cannula size could improve lower-limb perfusion and reduce the risk of hemolysis and thrombosis. Adding a lower limb diversion structure to a multiple side-hole cannula can further improve lower extremity diversion and reduce the risk of hemolysis and thrombosis. The findings of this study can provide guidance for optimizing the design of cannula configuration and improving cannula-related blood compatibility.

Purpose: Photon-counting detectors (PCDs) are cutting-edge technology that enable spectral computed tomography (CT) imaging with a single scan. Spectral imaging is particularly effective in contrast-enhanced CT (CECT) imaging, especially when multiple contrast agents are utilized, as materials are distinguishable based on their unique X-ray absorption. One application of CECT is joint imaging, where it assesses the structure and composition of articular cartilage soft tissue. This evaluates articular cartilage and reveals compositional changes associated with early-stage osteoarthritis (OA) using a photon-counting detector CT (PCD-CT) technique combined with a dual-contrast agent method.

Methods: A dual-contrast agent combination was used, consisting of proteoglycan-binding cationic tantalum oxide nanoparticles, developed in our lab, and a commercial non-ionic iodinated iodixanol agent. Ex vivo equine stifle joint cartilage samples (N = 30) were immersed in the contrast agent bath for 96 hours and imaged at multiple timepoints for analysis of proteoglycan, collagen, and water contents as well as collagen orientation, histological scoring, and biomechanical parameters.

Results: By analyzing contrast agent concentrations, the technique provided a simultaneous assessment of the solid constituents and function of cartilage. Contrast agent diffusion depended on contrast agent composition and was significantly different between healthy and early-stage OA groups within 12 hours.

Conclusion: The present study shows the promising utility of the dual-contrast PCD-CT technique for articular cartilage assessment and early-stage OA detection.

Introduction: Portable suction devices are crucial for emergency airway management. Commercially-available units are unsuitable for field use due to size and power needs. A light-weight and multi-orientation operable portable suction device, Battlefield Ready Innovative Suction Kit (BRISK) was developed. The design was informed by feedback from combat medics, paramedics, and EMTs.

Methods: End-user engagement and feedback defined BRISK's design. The fabricated prototype used a vacuum pump and hydrophobic syringe filters. Performance tests measured vacuum pressure, air and liquid (water and ISO vomit simulant) flow rates, volume of water suctioned in different orientations (upright, tilted, or inverted), and contamination prevention between BRISK, SSCOR Quickdraw, and Laerdal LCSU4.

Results: The BRISK device-weighing 0.97 kg-demonstrated a maximum vacuum pressure of 570 ± 6 mmHg and an air flowrate of 5.20 L/min. Liquid flow rates (L/min) for BRISK, LCSU4, and SSCOR with water were 4.92 ± 0.2, 6.97 ± 0.1, and 5.37 ± 0.1, respectively. With ISO vomit simulant, the rates were 3.23 ± 0.2, 3.06 ± 0.4, and 2.23 ± 0.1. BRISK showed consistent performance across orientations (p = 0.081), while LCSU4 and SSCOR varied significantly (p < 0.0001). The BRISK's cross-contamination between filters and the pump was 0.01%, which is far less than the  rated contamination level of 0.1% as described by ISO 10079-1.

Conclusion: BRISK is 30% lighter and achieves competitive vacuum pressures and liquid flow rates than comparable units currently in the market. It ensures effective evacuation of liquids in all orientations: upright, tilted, or inverted. These results demonstrate the BRISK has the potential to provide superior clinical performance in pre-hospital and first response scenarios.

Fracture fixation with standard locked plates can suppress interfragmentary motion beneficial for secondary bone healing. To address this limitation, dynamic fracture fixation plates have been developed which seek to maintain bending and torsional rigidity while providing controlled axial micromotion. This article provides a comprehensive systematic review of the history and current state of proposed dynamic plating technologies to better inform future development. 59 records (51 articles, 8 patents) describing 26 unique dynamic plating devices were identified across three literature and patent databases using PRISMA review guidelines. Concepts were grouped into one of 9 engineering approach categories, including plates that incorporate sliding mechanisms, elastic inserts, lattice structures, and mechanically compliant flexures, among others. Devices are compared in their technological characteristics, ranges of axial motion, stiffnesses, and levels of development. Despite many dynamic technologies demonstrating good healing results experimentally and clinically, widespread clinical adoption has not occurred. Some explanations for this are provided, including production costs for complex designs and the current co-existence of both rigid and flexible fixation approaches. Overall, dynamic plating offers a promising area of innovation to address the ongoing concerns of non-union rates associated with standard locked plating of long bone fractures.

Magnetic nanoparticles (MNPs) have revolutionized cancer therapy by serving as effective drug transporters through active and passive targeting of tumor sites in conjugation with external alternating magnetic fields (AMFs), thus minimizing off-target effects. This precise targeting strategy guarantees a focused and controlled drug release at the tumor site, reducing the drawbacks of standard drug delivery systems and enhancing treatment effectiveness. Magnetic nanoparticles usually follow in magnetic hyperthermia (MHT) therapy, where AMFs raise the temperature at the tumor site, efficiently eliminating cancer cells and presenting a hopeful complement to conventional cancer treatments. In addition, side effects are reduced by launching a smart drug delivery system (SDDSs) in which treatment efficacy is enhanced by reducing the dosage frequency. Intrinsic properties of MNPs are measured when they serve as contrast agents in magnetic resonance imaging (MRI), providing a diagnostic aspect to their therapeutic capabilities and enabling medical professionals to monitor and record treatment outcomes with precision and higher accuracy. This comprehensive review highlights the multifaceted potential of MNPs in reshaping cancer treatment, emphasizing their role in targeted drug delivery, hyperthermia therapy, and imaging applications, and underscoring their transformative impact on the future of oncological care.