Annals of Biomedical Engineering最新文献

{"title":"Effect of Posterior Element Removal in Thoracic and Lumbar Spine Segments With and Without Compromised Vertebral Microstructure Under Axial Compression.","authors":"Margherita Pasini, Gaia Youssef, Luca Cristofolini, Marco Palanca","doi":"10.1007/s10439-026-04341-0","DOIUrl":"https://doi.org/10.1007/s10439-026-04341-0","url":null,"abstract":"<p><strong>Purpose: </strong>Technical constraints often require biomechanical testing of spine segments after removal of the vertebral posterior elements, potentially introducing bias in the biomechanical outcomes. This study aimed to evaluate the effects of posterior elements removal on the biomechanics of thoracic and lumbar spine segments when axially compressed and to investigate whether these effects differ between control vertebrae (without CT evidence of pathological alterations) and vertebrae with compromised microstructure due to metastatic lesions.</p><p><strong>Methods: </strong>Fourteen thoracolumbar spine segments harvested from donors with spinal metastases were tested under axial compression within the elastic regime. Each specimen was tested before and after posterior elements removal, up to a specimen-specific reference force corresponding to a compressive strains of 2000 microstrain. Surface strain fields were quantified using three-dimensional digital image correlation. Reference force, stiffness and strain heterogeneity were evaluated.</p><p><strong>Results: </strong>Posterior element removal did not significantly affect the reference force or stiffness in thoracic specimens. By contrast, lumbar specimens required a lower reference force (- 43%) to reach the same strain and exhibited reduced stiffness (- 20%) following posterior elements removal. Strain heterogeneity increased only in lumbar specimens. Control vertebrae were minimally affected, whereas metastatic vertebrae exhibited a tendency towards heterogeneous strain pattern following posterior element removal.</p><p><strong>Conclusion: </strong>Posterior element removal introduces mechanical artefacts in lumbar spine testing under axial compression, while having minimal impact on thoracic segments. Therefore, caution is warranted when comparing biomechanical data obtained from intact and posterior-element-removed lumbar specimens, particularly in the presence of compromised bone microstructure due to metastatic lesions.</p>","PeriodicalId":7986,"journal":{"name":"Annals of Biomedical Engineering","volume":" ","pages":""},"PeriodicalIF":5.2,"publicationDate":"2026-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148787514","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Shear-Wave Anisotropy of the Vastus Lateralis During Low-Level Isometric Contraction Measured with Ultrasound Time-Harmonic Elastography.","authors":"Tom Meyer, Stefan Klemmer Chandía, Pascal Engl, Giacomo Valli, Yanglei Wu, Klaus Jenderka, Thomas Bartels, René Schwesig, Jing Guo, Eduard Kurz, Ingolf Sack, Hossein S Aghamiry","doi":"10.1007/s10439-026-04344-x","DOIUrl":"https://doi.org/10.1007/s10439-026-04344-x","url":null,"abstract":"<p><strong>Purpose: </strong>Skeletal muscle is commonly modeled as a transversely isotropic medium; however, the behavior of its anisotropy under active loading remains insufficiently characterized. In this study, we used ultrasound time-harmonic elastography (THE) to quantify direction-dependent shear-wave speed (SWS) in the vastus lateralis (VL) muscle at rest and during low isometric contraction intensities.</p><p><strong>Methods: </strong>Twenty-six healthy adults (15 men, 11 women; <math><mrow><mn>25.0</mn> <mo>±</mo> <mn>4.1</mn></mrow> </math>  y) underwent multi-frequency THE (60-80 Hz). The transducer was aligned parallel (longitudinal) and perpendicular (transverse) to VL fascicles, and measurements were acquired at rest and at 15% and 30% of maximal voluntary contraction (MVC). Fractional anisotropy (FA) was computed from <math><mrow><mi>S</mi> <mi>W</mi> <msub><mi>S</mi> <mo>‖</mo></msub> </mrow> </math> and <math><mrow><mi>S</mi> <mi>W</mi> <msub><mi>S</mi> <mo>⊥</mo></msub> </mrow> </math> , yielding zero for isotropic media. Orientation and contraction effects were tested with repeated-measures analyses.</p><p><strong>Results: </strong>At rest, longitudinal SWS exceeded transverse SWS ( <math><mrow><mn>2.5</mn> <mo>±</mo> <mn>0.2</mn></mrow> </math> vs. <math><mrow><mn>1.4</mn> <mo>±</mo> <mn>0.1</mn></mrow> </math>  m/s; paired t-test <math><mrow><mi>p</mi> <mo><</mo> <mn>0.01</mn></mrow> </math> ). With contraction, SWS increased to <math><mrow><mn>3.2</mn> <mo>±</mo> <mn>0.2</mn></mrow> </math> and <math><mrow><mn>3.8</mn> <mo>±</mo> <mn>0.3</mn></mrow> </math>  m/s (15%, 30% MVC) along fibers, and to <math><mrow><mn>1.6</mn> <mo>±</mo> <mn>0.1</mn></mrow> </math> and <math><mrow><mn>1.8</mn> <mo>±</mo> <mn>0.1</mn></mrow> </math>  m/s across fibers (all <math><mrow><mi>p</mi> <mo><</mo> <mn>0.01</mn></mrow> </math> ). A two-factor repeated-measures ANOVA on SWS showed main effects of orientation and contraction and a significant interaction (all <math><mrow><mi>p</mi> <mo><</mo> <mn>0.01</mn></mrow> </math> ). FA increased from <math><mrow><mn>0.37</mn> <mo>±</mo> <mn>0.04</mn></mrow> </math> at rest to <math><mrow><mn>0.43</mn> <mo>±</mo> <mn>0.04</mn></mrow> </math> at 15% and <math><mrow><mn>0.47</mn> <mo>±</mo> <mn>0.03</mn></mrow> </math> at 30% MVC ( <math><mrow><mi>p</mi> <mo><</mo> <mn>0.01</mn></mrow> </math> ). No sex- or BMI-related effects were detected.</p><p><strong>Conclusion: </strong>VL exhibited marked shear-wave anisotropy at rest that increased with low-level contraction intensities, indicating disproportionate stiffening along the fiber direction. THE provides a rapid, cost-effective, orientation-sensitive readout of muscle mechanics that may support studies of neuromuscular function and pathology.</p>","PeriodicalId":7986,"journal":{"name":"Annals of Biomedical Engineering","volume":" ","pages":""},"PeriodicalIF":5.2,"publicationDate":"2026-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148787492","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization of Collagen Fiber Organization in Breast Cancer via Model-Free Multiscale pSHG Image Analysis.","authors":"Giuseppe Lombardo, Raffaella Mercatelli, Giuseppe Massimo Bernava, Riccardo Cicchi","doi":"10.1007/s10439-026-04345-w","DOIUrl":"https://doi.org/10.1007/s10439-026-04345-w","url":null,"abstract":"<p><strong>Purpose: </strong>Alterations in collagen micro-architecture are hallmarks of tumor progression. Conventional polarization second-harmonic generation (pSHG) analyses rely on rigid symmetry assumptions that often fail in heterogeneous tissue microenvironments. We present a fully automated model-free, multiscale, computational framework designed for the unbiased quantification of complex collagen organization in breast cancer tissue.</p><p><strong>Methods: </strong>Breast tumor and adjacent perilesional tissues were imaged using a custom pSHG microscope and analyzed at micro- and meso-scale levels. Collagen centerlines were extracted via U-Net-based segmentation to estimate fiber orientations, while global alignment was quantified using 2D-FFT angular spectra. Structural organization was characterized with model-free descriptors, including scalar and biaxial order parameters and semi-variogram-based spatial autocorrelation.</p><p><strong>Results: </strong>Across a limited proof-of-concept dataset ( <math><mrow><mi>n</mi> <mo>=</mo> <mn>14</mn></mrow> </math> FoVs), the proposed multiscale framework effectively discriminated tumor from adjacent perilesional collagen architecture. The trigonal polarization model yielded smoother, more robust orientation maps than the cylindrical approach, showing strong agreement with deep learning fiber centerline analysis ( <math><mrow><mi>C</mi> <mi>C</mi> <mi>C</mi> <mo>=</mo> <mn>0.985</mn></mrow> </math> ). Tumor regions exhibited significantly longer spatial coherence length (87.3 ± 22.1 µm vs. 44.2 ± 11.3 µm, P = 0.01), higher scalar order (0.81 ± 0.06 vs. 0.56 ± 0.05, P = 0.01), and elevated biaxial order (0.12 ± 0.02 vs. 0.06 ± 0.06, P < 0.05).</p><p><strong>Conclusions: </strong>This seminal framework provides a robust and assumption-free methodology to extract quantitative collagen descriptors across spatial scales. By integrating deep learning, frequency-domain analysis, and spatial statistics, it captures both local and long-range organizational features, supporting collagen architecture as a potential quantitative multiscale biomarker of tumor-associated extracellular matrix remodeling.</p>","PeriodicalId":7986,"journal":{"name":"Annals of Biomedical Engineering","volume":" ","pages":""},"PeriodicalIF":5.2,"publicationDate":"2026-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148787518","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"One-Click CT-Based Pipeline for Regional Quantification of Aortic Valve Fibrocalcific Degeneration.","authors":"Marta Liberotti, Anna Palmisano, Alberto Colombo, Davide Vignale, Federica Piccione, Marco Bruno Ancona, Matteo Montorfano, Antonio Esposito","doi":"10.1007/s10439-026-04272-w","DOIUrl":"https://doi.org/10.1007/s10439-026-04272-w","url":null,"abstract":"<p><strong>Purpose: </strong>Aortic Stenosis (AS) involves progressive fibrocalcific degeneration of the aortic valve. Current imaging methods for valve tissue quantification remain semi-automated and lack detailed spatial tissue characterization. We present a CT-based pipeline that fully automates the quantification of fibrotic and calcific components and enables semi-automated regional tissue analysis.</p><p><strong>Methods: </strong>We developed a standardized pipeline that performs automatic multiplanar reconstruction of pre-TAVI cardiac CT scans, automatic fibrocalcific volume quantification, and semi-automated regional volume assessment requiring only a single user input. We evaluated the accuracy of the pipeline by comparing each module with manual analyses performed independently by two radiologists with different levels of expertise. Agreement between automated and manual results was assessed using Bland-Altman analysis and standard similarity metrics.</p><p><strong>Results: </strong>We analyzed 25 patients with severe AS (13 females/12 males; median age 82 years, IQR 78-86). The pipeline processed for each patient in ≤ 2.5 min. Multiplanar reconstruction showed an angular error of 5.38° (IQR 3.29-8.33) between the expert user and the pipeline. Bland-Altman analysis revealed minimal bias for fibrocalcific volume and density, comparable to inter-user variability. Expert-pipeline Dice coefficients for regional divisions were high (0.86-0.89), and entropy of fibrocalcific ratio demonstrated substantial tissue heterogeneity among patients.</p><p><strong>Conclusion: </strong>The proposed pipeline enables accurate assessment of aortic valve disease severity by integrating fibrotic and calcific quantification with spatial distribution, offering potential to inform TAVI planning and clinical decision-making with minimal user input and analysis time.</p><p><strong>Trial registration: </strong>NCT06029400, registered on 1 September 2023.</p>","PeriodicalId":7986,"journal":{"name":"Annals of Biomedical Engineering","volume":" ","pages":""},"PeriodicalIF":5.2,"publicationDate":"2026-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148787468","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of Crew Seat Inclination on Multi-Organ Injury Risk in Astronauts During Off-Nominal High-g Landing Impact.","authors":"Xin Ma, Dongmei Wang, Yutan Wang, Fang Wang, Aili Qu","doi":"10.1007/s10439-026-04334-z","DOIUrl":"https://doi.org/10.1007/s10439-026-04334-z","url":null,"abstract":"<p><strong>Purpose: </strong>During off-nominal landings, spacecraft reentry capsules can experience impact accelerations far exceeding the 8-12 g typical of nominal returns, with peak values surpassing 50 g and rise times under 100 ms. Such loading conditions pose multi-organ injury risks to astronauts. This study systematically investigates how seatback inclination modulates these risks.</p><p><strong>Methods: </strong>Drop tower tests were performed at three severity levels (Low: 18 g, Mid: 32 g, High: 45 g) using a Hybrid III 50th percentile male anthropomorphic test device. The measured velocity pulses then drove THUMS AM50 v7.0 simulations across five seatback inclinations (0°, 10°, 20°, 30°, 40°). Injury risk was evaluated using dynamic injury criteria (HIC₁₅, N_ij, Thoracic Dmax, and Lumbar Fmax) supplemented by tissue-level mechanical parameters (Brain CSDM0.2, Lung MPS and CSDM0.343, Myocardial VMS, Aorta MPS). Segmented linear regression with logit-transformed probabilities quantified the inclination-injury probability relationship. A sensitivity analysis varying the occupant-seat contact condition (friction coefficient ± 50%) tested for cross-over interactions and assess the robustness of the inclination angle rankings.</p><p><strong>Results: </strong>All dynamic injury criteria worsened monotonically with increasing inclination; the lumbar spine were the most sensitive region. Tissue-level responses revealed conflicting organ-specific demands: Brain CSDM0.2 and Aorta MPS reached minima at 0°, Lung MPS at 40°, while Myocardial VMS displayed a U-shaped minimum near 20°. Lung MPS and Lung CSDM0.343 trended in opposite directions-peak local strain was highest at 0°, whereas the volume fraction exceeding the injury threshold peaked at 40°-indicating a shift in lung deformation mode from localized compression to diffuse stretching. Segmented regression confirmed that injury risk is strongly correlated with seat inclination, with risk ratios per degree ranging from 1.003 (neck, Low impact) to 1.739 (lumbar, beyond 10°). The sensitivity analysis detected no cross-over interactions, confirming that the relative ranking of inclinations was robust to variations in contact conditions.</p><p><strong>Conclusion: </strong>No single inclination simultaneously minimized injury risk across all anatomical regions. The supine posture (0°) offered the greatest protection for the brain, spine, and aorta, but maximized lung strain. A lower inclination range (0°-20°) provided a more favorable overall balance than substantially reclined postures (30°-40°), though the precise optimum differed by organ system. These findings provide quantitative guidance for adaptive crew restraint system design.</p>","PeriodicalId":7986,"journal":{"name":"Annals of Biomedical Engineering","volume":" ","pages":""},"PeriodicalIF":5.2,"publicationDate":"2026-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148757376","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of Joint Kinematics and Spatiotemporal Gait Parameters Between Markerless and Marker-Based Motion Capture in a Large Knee Osteoarthritis Cohort.","authors":"Junqing Wang, Qiang Zhang, Biao Wang, Tao Deng, Imran Khan Niazi, Yong Nie, Kang Li","doi":"10.1007/s10439-026-04339-8","DOIUrl":"https://doi.org/10.1007/s10439-026-04339-8","url":null,"abstract":"<p><strong>Purpose: </strong>Theia3D, a markerless motion capture system, offers a practical alternative to marker-based systems for movement assessment. However, its concurrent validity in patients with knee osteoarthritis remains unevaluated. This study aimed to evaluate the concurrent validity of Theia3D against a marker-based system in measuring joint kinematics and spatiotemporal gait parameters in patients with knee osteoarthritis and to compare error metrics between patients and healthy controls.</p><p><strong>Methods: </strong>A total of 162 patients with advanced knee osteoarthritis and 50 healthy controls performed self-selected speed walking and sit-to-stand tasks. Data were simultaneously collected using markerless and marker-based systems. Measurement agreement and errors for spatiotemporal and kinematic parameters were assessed using Bland-Altman analysis, mean difference, Pearson correlation, intraclass correlation coefficient (ICC), and root mean square error (RMSE). Group differences in ICC and RMSE were evaluated using independent-samples t tests or Wilcoxon rank-sum tests.</p><p><strong>Results: </strong>Theia3D showed excellent agreement and very strong correlation with the marker-based system for spatiotemporal gait parameters. Sagittal hip and knee angles demonstrated good to excellent agreement, while agreement in most frontal and transverse joint angles was poor. Compared to controls, knee osteoarthritis patients showed significantly lower ICCs and higher RMSEs for certain joint angles.</p><p><strong>Conclusion: </strong>These findings suggest that Theia3D has potential as an alternative to marker-based systems for assessing spatiotemporal gait parameters and sagittal knee angles during walking. However, since most joint angle errors exceed the 5° clinical acceptability threshold, future work should expand training datasets to include diverse clinical populations and refine algorithms to enable broader clinical implementation.</p>","PeriodicalId":7986,"journal":{"name":"Annals of Biomedical Engineering","volume":" ","pages":""},"PeriodicalIF":5.2,"publicationDate":"2026-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148757571","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Publisher Correction: Inertial Microfluidic Separation of Cell Clusters from Blood Cells in Meandering Channels.","authors":"Ivan Cimrák, Michal Mulík, Monika Smiešková, Alžbeta Bugáňová, Yuhao Qiang, Franciele Flores Vit, Jianlu Zheng, Ming Dao","doi":"10.1007/s10439-026-04346-9","DOIUrl":"https://doi.org/10.1007/s10439-026-04346-9","url":null,"abstract":"","PeriodicalId":7986,"journal":{"name":"Annals of Biomedical Engineering","volume":" ","pages":""},"PeriodicalIF":5.2,"publicationDate":"2026-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148759317","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Full Leg Optimization (FLO): A Framework to Concurrently Design Low-Cost Passive Prosthetic Feet and Knees.","authors":"Nina T Petelina, Amanda L Shorter, Marina Tutuianu Cpo, Amos G Winter V","doi":"10.1007/s10439-026-04320-5","DOIUrl":"https://doi.org/10.1007/s10439-026-04320-5","url":null,"abstract":"<p><strong>Purpose: </strong>The mobility and life quality of a user with an above-knee amputation depend on the performance of their prosthetic leg. Prosthetic leg performance is a result of the quality of the prosthetic components, the interaction between them, and the availability of continuous care. Access to these factors is limited in low- and middle-income countries where the majority of lower limb amputees live. This study presents a method to design prosthetic legs based on the operation of all components in tandem to minimize the time for adjustment and the cost of a prosthetic leg.</p><p><strong>Methods: </strong>The full leg optimization (FLO) framework provides a method to quantitatively design prosthetic legs by predicting the interaction of the prosthetic foot and prosthetic knee at the initiation of knee flexion during the late stance phase. A prosthetic leg was designed for a person with an above-knee amputation, consisting of a Hip Trajectory Error foot and a passive prosthetic knee. The leg was designed so that the prosthetic knee would unlock at <math><mrow><mn>72</mn> <mo>%</mo></mrow> </math> of stance based on the predicted interaction of the foot and knee.</p><p><strong>Results: </strong>The preliminary results demonstrate consistent knee unlocking at <math><mrow><mn>73</mn> <mo>±</mo> <mn>3.8</mn> <mo>%</mo></mrow> </math> of stance after minimal acclimation time.</p><p><strong>Conclusion: </strong>This suggests that the FLO framework can accurately predict the interaction between the prosthetic foot and the prosthetic knee. Hence, the FLO framework is a design method for prosthetic legs for users with an above-knee amputation, providing a predictable performance, which would be beneficial for users living in low-resource settings.</p>","PeriodicalId":7986,"journal":{"name":"Annals of Biomedical Engineering","volume":" ","pages":""},"PeriodicalIF":5.2,"publicationDate":"2026-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148761376","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Automated Setup of CT-Based Vertebral Finite Element Simulations: Quantifying the Influence of Boundary-Condition Components on Fracture-Load Estimates.","authors":"Daniel Strack, Sara Amenini, Nico Sollmann, Tanja Lerchl, Jan S Kirschke, Dario Gastaldi, Karupppasamy Subburaj","doi":"10.1007/s10439-026-04314-3","DOIUrl":"10.1007/s10439-026-04314-3","url":null,"abstract":"<p><strong>Purpose: </strong>To develop and evaluate an automated workflow for the setup of single-vertebra finite element (FE) simulations from clinical CT data. Specifically, we quantified how automated endplate identification, vertebra-specific coordinate system definition, and load-application-point assignment influence the simulated fracture-load estimates.</p><p><strong>Methods: </strong>We analyzed 113 vertebrae from 70 patients that had previously undergone manual FE setup. The automated pipeline identified vertebral endplates, assigned a vertebra-specific coordinate system, and assigned the load application point for axial compression simulations. Automated setups were visually graded as good, acceptable, or bad using predefined criteria. Agreement with manual reference models was evaluated, and the effects of each setup component on fracture-load estimates were quantified separately.</p><p><strong>Results: </strong>Of 113 vertebrae, 53 (47%) automated setups were graded good, 40 (35%) acceptable, and 20 (18%) bad. In the good subset, fully automated models showed strong agreement with manual reference workflow (R² = 0.950), with a median percent difference in fracture-load estimate of 13.0% (95% CI, 9.0% to 15.3%). Among individual setup components, endplate identification produced the smallest change in fracture-load estimates, followed by coordinate-system definition, whereas the load-application-point assignment produced the largest deviations and the widest limits of agreement. Changes in load-point location showed the clearest association with changes in fracture-load estimates, whereas endplate-area differences showed no clear association.</p><p><strong>Conclusion: </strong>Automated setup of vertebral FE simulations can reduce manual intervention and support scalable processing, but current robustness remains insufficient for fully unsupervised use. In successfully processed cases, the workflow showed strong agreement with a manually configured reference workflow and identified load-point assignment as the most influential boundary-condition component in fracture-load estimates.</p>","PeriodicalId":7986,"journal":{"name":"Annals of Biomedical Engineering","volume":" ","pages":""},"PeriodicalIF":5.2,"publicationDate":"2026-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148719970","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Physics-Informed Reconstruction of Transmural Myocardial Deformation from 3D Echocardiography: Validation Against Cardiac MRI.","authors":"Satya Prakash Pradhan, Arash Yavari, Issac D Lindley, Nader Binesh, Yuri P Matusov, Kambiz Ghafourian, Gianni Pedrizzetti, Arash Kheradvar","doi":"10.1007/s10439-026-04335-y","DOIUrl":"10.1007/s10439-026-04335-y","url":null,"abstract":"<p><strong>Purpose: </strong>Quantitative assessment of myocardial deformation is increasingly important in clinical cardiology, yet conventional two-dimensional (2D) echocardiography and standard three-dimensional (3D) approaches remain limited by out-of-plane motion and incomplete characterization of transmural mechanics. To address these limitations, we introduce a physics-informed framework for 3D echocardiography that reconstructs the full finite strain tensor across the entire myocardial wall. As an initial methodological study, we demonstrate the framework and validate it against cardiac magnetic resonance in a small cohort.</p><p><strong>Methods: </strong>Endocardial and epicardial surfaces were segmented from 3D echocardiographic datasets and tracked throughout the cardiac cycle using speckle-tracking techniques. An optimization framework with a soft volumetric penalty was implemented, permitting volume change at finite cost while maintaining tracking fidelity and geometric smoothness. The resulting deformation field enabled reconstruction of the complete 3D strain tensor. Global strain measurements derived from the method were validated against cardiac magnetic resonance (CMR) measurements obtained in two subjects.</p><p><strong>Results: </strong>Global longitudinal and circumferential strain values obtained from the proposed framework showed strong agreement with CMR measurements. The optimization procedure also demonstrated robustness to segmentation variability and reduced errors associated with epicardial tracking. Beyond conventional strain indices, the method enabled reconstruction of spatially resolved principal strain fields throughout the ventricular wall, revealing physiologically consistent transmural gradients and contraction patterns.</p><p><strong>Conclusion: </strong>Physics-informed integration of speckle tracking with biomechanical constraints enables robust reconstruction of 3D myocardial deformation from echocardiography. This framework provides a comprehensive and physically consistent characterization of myocardial mechanics from widely available 3D echocardiographic data. These initial results support the feasibility of the proposed framework and motivate future evaluation in larger, more diverse patient cohorts to establish its clinical reliability.</p>","PeriodicalId":7986,"journal":{"name":"Annals of Biomedical Engineering","volume":" ","pages":""},"PeriodicalIF":5.2,"publicationDate":"2026-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13532400/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148722163","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}