Journal of biomechanics最新文献_第3页

1D Network computational fluid dynamics for evaluating regional pressures in subjects with cement dust exposure 一维网络计算流体动力学用于评估水泥粉尘暴露受试者的区域压力。

IF 2.4 3区医学 Q3 BIOPHYSICS

Journal of biomechanics

Pub Date : 2025-02-01 DOI: 10.1016/j.jbiomech.2025.112501

Minh Tam Tran , Quoc Hung Nguyen , Xinguang Cui , Kum Ju Chae , Sujeong Kim , Ji-Seung Yoo , Sanghun Choi

Cement dust is a primary contributor to air pollution and is responsible for causing numerous respiratory diseases. The impact of cement dust exposure on the respiratory health of residents is increasing owing to the demand for construction associated with urbanization. Long-term inhalation of cement dust leads to a reduction in lung function, alterations in airway structure, increased inhalation and exhalation resistance, and heightened work of breath. In this study, we investigated the effects of cement dust exposure on lung function based on the pulmonary function test (PFT) and one-dimensional computational fluid dynamics (1D CFD). Statistical tests were performed to address the disparity of airway function between healthy and cement dust-exposed participants. The percent predicted values of forced vital capacity percent (FVC%) and forced expiratory volume in 1 s (FEV₁%) were found to be decreased in the group of dust-exposed participants. An elevation of regional pressure variation was found in cement dust-exposed airways during both inhalation and exhalation that was associated with alternations of airway structural features therein. The 1D CFD model is beneficial for a cost-effective estimation of airway regional pressure and provides valuable insights for more precise diagnosis and treatment planning in individuals exposed to cement dust.

水泥粉尘是造成空气污染的主要因素，并导致许多呼吸系统疾病。由于城市化建设的需求，水泥粉尘暴露对居民呼吸健康的影响正在增加。长期吸入水泥粉尘会导致肺功能下降，气道结构改变，吸入和呼出阻力增加，呼吸功增加。本研究基于肺功能测试（PFT）和一维计算流体动力学（1D CFD）研究水泥粉尘暴露对肺功能的影响。进行统计检验以解决健康和水泥粉尘暴露参与者之间气道功能的差异。1 s内用力肺活量百分比预测值（FVC%）和用力呼气量（FEV1%）的百分比预测值在粉尘暴露组有所降低。在吸入和呼出期间，在暴露于水泥粉尘的气道中发现区域压力变化的升高，这与气道结构特征的改变有关。一维CFD模型有助于经济有效地估计气道区域压力，并为水泥粉尘暴露个体的更精确诊断和治疗计划提供有价值的见解。

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引用次数: 0

Classification of young adult motor fluctuation phenotypes in gait 年轻人步态运动波动表型的分类。

IF 2.4 3区医学 Q3 BIOPHYSICS

Journal of biomechanics

Pub Date : 2025-02-01 DOI: 10.1016/j.jbiomech.2025.112523

Christopher A. Bailey, Alexandre Mir-Orefice, Julie Nantel, Ryan B. Graham

Stride-to-stride fluctuations are natural in gait. These fluctuations are marked by inter-individual variability, suggesting that different fluctuation strategies (i.e., phenotypes) may exist. This study investigates the presence of gait fluctuation phenotypes. Whole-body kinematics were measured from young, healthy males and females (N = 51) while walking on a treadmill at their preferred speed. Motor fluctuation metrics (i.e., magnitude of variability, local dynamic stability, and regularity) were measured for 32 joint angles across the upper and lower body. These metrics were reduced to principal components (PCs) via principal component analysis and then grouped into clusters using the k-means method. One-way ANOVAs were conducted to test for cluster differences in motor fluctuation PCs. Three PCs were extracted, explaining 39.7 % of all 96 motor fluctuation metrics. Higher PC1 scores represent more fluctuation across all joints, higher PC2 scores represent greater upper limb fluctuations with fewer fluctuations in the lower limb, and PC3 scores represent less regularity in fluctuations. PC scores best grouped into four clusters in 54.0 % of iterations. Clusters 1–4 each had a significantly different PC1 score (p < 0.022), and Cluster 3 had a higher PC2 score than all other clusters (p < 0.022). Motor fluctuations in treadmill gait of young adults were characterised by four gait fluctuation phenotypes, interpreted as repeaters, replacers, moderate fluctuators, and mixed fluctuators (i.e. more upper limb but fewer lower limb fluctuations); extending the repeaters vs replacers hypothesis. The identified phenotypes add a new perspective that may help clarify the link between motor fluctuations and gait instability.

步幅之间的波动是步态的自然变化。这些波动以个体间差异为特征，表明可能存在不同的波动策略（即表型）。本研究调查步态波动表型的存在。研究人员测量了51名年轻、健康的男性和女性在跑步机上以自己喜欢的速度行走时的全身运动学。测量上半身和下半身32个关节角度的运动波动指标（即变异性的大小、局部动态稳定性和规律性）。通过主成分分析将这些指标简化为主成分（pc），然后使用k-means方法将其分组为簇。采用单因素方差分析检验运动波动pc的聚类差异。提取了3个pc，解释了全部96个电机波动指标的39.7%。PC1得分越高，代表所有关节的波动越大；PC2得分越高，代表上肢波动越大，下肢波动越少；PC3得分代表波动的规律性越小。在54.0%的迭代中，PC得分最高的是四组。各组1-4的PC1评分差异有统计学意义(p

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引用次数: 0

Modified chevron osteotomy for the treatment of hallux valgus with unison bioabsorbable screws: Biomechanical research and clinical applications 改良v形截骨术治疗拇外翻的生物力学研究及临床应用。

IF 2.4 3区医学 Q3 BIOPHYSICS

Journal of biomechanics

Pub Date : 2025-02-01 DOI: 10.1016/j.jbiomech.2025.112527

Changyi Liu , Dongqi Li , Songning Ma , Hanyang Zhang , Shizhong Zhang , Fei Chang , Peng Liu , Hongwei Zhao , Shuo Jin

Researchers have modified PLA materials to enhance their mechanical properties and meet the clinical requirements. However, the strength and stiffness of PLA are still significantly lower than those of metals. Building on the established chevron clinical procedure and considering the mechanical characteristics of PLA screws, we devised a modified chevron osteotomy (MCO) based on a load-reducing structure with the aim of reducing the load on the screws. Subsequently, in vitro quasi-static in situ compression and dynamic fatigue tests were conducted for both procedures. DIC, micro-CT, and SEM were used to elucidate the unloading effects and structural damage of different bone cutting and implant locations on the PLA bone screws, providing biomechanical data for clinical applications. In-vitro simulation studies indicated that the unloading structure of the MCO procedure reduced the load borne by the PLA screws. Within the load range of the first metatarsal during walking, the MCO procedure exhibited a compressive strength 2.5 times that of the traditional chevron osteotomy groups and even exceeded the titanium alloy screw groups by 25%, ensuring PLA screw fixation strength and stability that are not inferior to metallic materials. A stable load-reducing structure in osteotomy procedures is the key to PLA materials becoming viable alternatives to metal orthopedic fixation devices.

研究人员对聚乳酸材料进行了改性，以提高其力学性能，满足临床要求。然而，PLA的强度和刚度仍然明显低于金属。基于已建立的三角形临床手术并考虑PLA螺钉的力学特性，我们设计了一种基于减载结构的改良三角形截骨术（MCO），目的是减少螺钉的负荷。随后，对这两种工艺进行了体外准静态原位压缩和动态疲劳试验。采用DIC、micro-CT、SEM等技术研究不同切骨位置和种植体位置对PLA骨螺钉的卸载效应和结构损伤，为临床应用提供生物力学数据。体外模拟研究表明，MCO程序的卸载结构降低了PLA螺钉所承受的载荷。在行走时第一跖骨负荷范围内，MCO手术的抗压强度是传统v形截骨组的2.5倍，甚至超过钛合金螺钉组25%，PLA螺钉的固定强度和稳定性不逊于金属材料。在截骨术中，稳定的减载结构是PLA材料成为金属骨科固定装置可行替代品的关键。

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引用次数: 0

Reliable and streamlined model setup for digital twin assessment of fracture healing

IF 2.4 3区医学 Q3 BIOPHYSICS

Journal of biomechanics

Pub Date : 2025-02-01 DOI: 10.1016/j.jbiomech.2025.112492

Mehran Bahrami , Kylie Frew , John Hughes , Hannah L. Dailey

In large animal models of bone fracture repair, postmortem torsional testing is commonly used to assess healing biomechanics. Bending and axial tests are physiologically relevant, but much less commonly performed. Virtual torsional testing using image-based finite element models has been validated to postmortem bench tests, but its predictive value for capturing whole-bone mechanics and fracture healing quality under other physiologically relevant loading modes has not yet been established. Accordingly, the purpose of this study was to evaluate the association between mechanical biomarkers derived from virtual torsion, axial, and bending tests under strict alignment and malalignment conditions. Computed tomography (CT) scans from 24 intact and operated sheep tibiae and 29 human tibial fractures were used to create digital twins that were subjected to torsion, axial, and bending tests. The results indicated that torsional rigidity is a strong surrogate for bending flexural rigidity in both ovine and human bones. Torsional rigidity and axial stiffness were strongly correlated in the ovine data, but only moderately in human fractures due to the complex fracture patterns. Axial testing was highly prone to stiffness estimation errors as high as 50% if the applied load and anatomic axis were not perfectly aligned. In contrast, torsional rigidity had errors <1.3% for all malalignment scenarios. Based on this study, virtual torsional rigidity is the recommended summary mechanical biomarker of bone healing because it captures variations in healing biomechanics that are present in other loading modes with a simple setup that is insensitive to alignment error.

在骨折修复的大型动物模型中，死后扭转测试通常用于评估愈合的生物力学。弯曲和轴向测试与生理相关，但较少进行。使用基于图像的有限元模型进行的虚拟扭转测试已通过死后台架测试的验证，但其在其他生理相关加载模式下捕捉全骨力学和骨折愈合质量的预测价值尚未确定。因此，本研究的目的是评估在严格对齐和错位条件下进行虚拟扭转、轴向和弯曲测试所得出的力学生物标志物之间的关联。研究人员利用 24 根完整和手术过的绵羊胫骨以及 29 根人类胫骨骨折的计算机断层扫描（CT）创建了数字双胞胎，并对其进行了扭转、轴向和弯曲测试。结果表明，在绵羊和人类骨骼中，扭转刚度是弯曲挠曲刚度的有力替代物。在绵羊的数据中，扭转刚度和轴向刚度具有很强的相关性，但在人类骨折中，由于骨折形态复杂，扭转刚度和轴向刚度仅具有适度的相关性。如果施加的载荷和解剖轴线不完全一致，轴向测试极易产生高达50%的刚度估计误差。相比之下，扭转刚度的误差为

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引用次数: 0

BIASMECHANICS: Does an unconscious bias still persist in biomechanics, positioning males as the default in human research? A meta-analysis on the Journal of Biomechanics 2024 publications

IF 2.4 3区医学 Q3 BIOPHYSICS

Journal of biomechanics

Pub Date : 2025-01-31 DOI: 10.1016/j.jbiomech.2025.112560

Eline van der Kruk

Articles published in the Journal of Biomechanics still reflect bias, with males positioned as the default in human research. This meta-analysis on the 2024 articles reveals a large disparity in female representation. One in four studies showed an imbalance (<30 % female representation) favouring male participants, while only 8 % favoured females. Male-only studies outnumbered female-only studies by over fivefold. Of particular concern is that male-only studies often lack justification for their single-gender focus, whereas female-only studies typically provide clear reasoning. This inconsistency not only lacks accountability but also reinforces the notion that male data is the standard in biomechanics research. I named this issue biasmechanics to encourage efforts to address them. While there are valid scientific reasons for focusing on specific gender/sex groups, this should not be the default. Authors must consider sex- and gender-based differences, and reviewers and editors should adopt stricter standards for accepting articles with unjustified imbalances. The Journal of Biomechanics could establish standardized guidelines promoting equitable representation in research. Exclusions of any sex or gender must include clear scientific justification in the introduction and methodology sections. The discussion and limitations sections should assess the implications of such exclusions, including their effects on validity, generalizability, and bias. If appropriate, titles and abstracts should clearly indicate single-sex or gender-specific studies to ensure transparency about the research’s scope and applicability. By collectively affirming as a scientific community that, except for legitimate scientific justification, we oppose the exclusion of female participants, we can shift the default approach in our research studies.

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引用次数: 0

Bone mineral density surrounding the screw thread predicts the risk of pedicle screw loosening

IF 2.4 3区医学 Q3 BIOPHYSICS

Journal of biomechanics

Pub Date : 2025-01-30 DOI: 10.1016/j.jbiomech.2025.112542

Yize Jiang , Yi Wei , Yuxuan Liu , Jiaxu Yang , Kexin Zhou , Haisheng Yang

Background

Screw loosening remains a serious complication for patients undergoing pedicle screw fixation surgeries. An accurate risk prediction is significant for prevention of screw loosening through preoperative planning. In this study, we proposed a novel index, namely the bone mineral density surrounding the screw thread (thread BMD), and tested its predictability in screw loosening.

Methods

86 screws (18 loosening and 68 non-loosening) from L3–L5 of 20 patients who experienced pedicle screw loosening were analyzed. The preoperative and postoperative quantitative CT scans of the same vertebra were spatially registered and a helix-based approach was developed to extract the thread BMD. BMDs of the vertebral body, the pedicle and the screw trajectory were also measured from the preoperative CT scans. Finite element analysis was conducted to determine pullout strength and tissue failure around the screw. Receiver operating characteristic (ROC) curve analysis was used to assess the performances of all BMD indices and pullout strength in predicting screw loosening. Linear regression was used to examine correlations between different BMD indices and screw pullout strength.

Results

The thread BMD had the greatest value of area under the curve (AUC = 0.73, p = 0.004) compared to vertebral BMD (AUC = 0.51, p = 0.923), pedicle BMD (AUC = 0.56, p = 0.474) and trajectory BMD (AUC = 0.67, p = 0.020). Also, the thread BMD showed a stronger correlation with the pullout strength (r = 0.83, p < 0.001) than vertebral BMD (r = 0.59, p < 0.001), pedicle BMD (r = 0.65, p < 0.001) and trajectory BMD (r = 0.60, p < 0.001).

Conclusions

We developed a novel approach to measure a newly-defined thread BMD, which indicates superior capacities over other BMD indices in predicting pedicle screw loosening.

{"title":"Bone mineral density surrounding the screw thread predicts the risk of pedicle screw loosening","authors":"Yize Jiang , Yi Wei , Yuxuan Liu , Jiaxu Yang , Kexin Zhou , Haisheng Yang","doi":"10.1016/j.jbiomech.2025.112542","DOIUrl":"10.1016/j.jbiomech.2025.112542","url":null,"abstract":"<div><h3>Background</h3><div>Screw loosening remains a serious complication for patients undergoing pedicle screw fixation surgeries. An accurate risk prediction is significant for prevention of screw loosening through preoperative planning. In this study, we proposed a novel index, namely the bone mineral density surrounding the screw thread (thread BMD), and tested its predictability in screw loosening.</div></div><div><h3>Methods</h3><div>86 screws (18 loosening and 68 non-loosening) from L3–L5 of 20 patients who experienced pedicle screw loosening were analyzed. The preoperative and postoperative quantitative CT scans of the same vertebra were spatially registered and a helix-based approach was developed to extract the thread BMD. BMDs of the vertebral body, the pedicle and the screw trajectory were also measured from the preoperative CT scans. Finite element analysis was conducted to determine pullout strength and tissue failure around the screw. Receiver operating characteristic (ROC) curve analysis was used to assess the performances of all BMD indices and pullout strength in predicting screw loosening. Linear regression was used to examine correlations between different BMD indices and screw pullout strength.</div></div><div><h3>Results</h3><div>The thread BMD had the greatest value of area under the curve (AUC = 0.73, p = 0.004) compared to vertebral BMD (AUC = 0.51, p = 0.923), pedicle BMD (AUC = 0.56, p = 0.474) and trajectory BMD (AUC = 0.67, p = 0.020). Also, the thread BMD showed a stronger correlation with the pullout strength (r = 0.83, p < 0.001) than vertebral BMD (r = 0.59, p < 0.001), pedicle BMD (r = 0.65, p < 0.001) and trajectory BMD (r = 0.60, p < 0.001).</div></div><div><h3>Conclusions</h3><div>We developed a novel approach to measure a newly-defined <em>thread BMD</em>, which indicates superior capacities over other BMD indices in predicting pedicle screw loosening.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"181 ","pages":"Article 112542"},"PeriodicalIF":2.4,"publicationDate":"2025-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143074462","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Establishing a threshold for total joint moment asymmetry in asymptomatic adults

IF 2.4 3区医学 Q3 BIOPHYSICS

Journal of biomechanics

Pub Date : 2025-01-29 DOI: 10.1016/j.jbiomech.2025.112559

Carson Halliwell , Janie Astephen Wilson , Derek Rutherford , Aleksandra Budarick , Meaghan Hannigan , Rebecca Moyer

Gait analysis is a fundamental tool for understanding joint function and identifying asymmetries in joint moments, which can signal underlying pathologies or potential risk factors for joint damage. Despite the widespread use of symmetry analysis in assessing gait across various conditions, including osteoarthritis and post-injury recovery, there remains no clear objective evidence on joint moment symmetry in healthy adults to serve as a comparison for pathological populations. This study aimed to define the range of joint moment asymmetry during walking in healthy adults. Twenty-one asymptomatic individuals aged 40 years and older underwent three-dimensional gait analysis at a self-selected walking speed. The total knee joint moment was calculated as a composite measure of the net external knee frontal, sagittal, and transverse moments, and absolute inter-limb asymmetry in the total knee joint moment was calculated for all participants. Paired samples t-tests were used to assess for differences in total knee joint, frontal, sagittal, and transverse moments between knees. No significant differences in any knee joint moment outcomes were found between knees. Findings indicated that the upper limit of absolute total joint moment asymmetry in asymptomatic individuals was 14 %. The establishment of this threshold provides a critical reference for clinicians and researchers to identify asymmetries that may deviate from healthy adult ranges.

{"title":"Establishing a threshold for total joint moment asymmetry in asymptomatic adults","authors":"Carson Halliwell , Janie Astephen Wilson , Derek Rutherford , Aleksandra Budarick , Meaghan Hannigan , Rebecca Moyer","doi":"10.1016/j.jbiomech.2025.112559","DOIUrl":"10.1016/j.jbiomech.2025.112559","url":null,"abstract":"<div><div>Gait analysis is a fundamental tool for understanding joint function and identifying asymmetries in joint moments, which can signal underlying pathologies or potential risk factors for joint damage. Despite the widespread use of symmetry analysis in assessing gait across various conditions, including osteoarthritis and post-injury recovery, there remains no clear objective evidence on joint moment symmetry in healthy adults to serve as a comparison for pathological populations. This study aimed to define the range of joint moment asymmetry during walking in healthy adults. Twenty-one asymptomatic individuals aged 40 years and older underwent three-dimensional gait analysis at a self-selected walking speed. The total knee joint moment was calculated as a composite measure of the net external knee frontal, sagittal, and transverse moments, and absolute inter-limb asymmetry in the total knee joint moment was calculated for all participants. Paired samples t-tests were used to assess for differences in total knee joint, frontal, sagittal, and transverse moments between knees. No significant differences in any knee joint moment outcomes were found between knees. Findings indicated that the upper limit of absolute total joint moment asymmetry in asymptomatic individuals was 14 %. The establishment of this threshold provides a critical reference for clinicians and researchers to identify asymmetries that may deviate from healthy adult ranges.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"181 ","pages":"Article 112559"},"PeriodicalIF":2.4,"publicationDate":"2025-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143080078","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Artificial neural networks’ estimations of lower-limb kinetics in sidestepping: Comparison of full-body vs. lower-body landmark sets

IF 2.4 3区医学 Q3 BIOPHYSICS

Journal of biomechanics

Pub Date : 2025-01-27 DOI: 10.1016/j.jbiomech.2025.112548

Yulin Zhou , Shengxing Fu , Tianqi Yao , Hui Liu , Hanjun Li

Artificial neural networks (ANNs) offers potential for obtaining kinetics in non-laboratory. This study compared the estimation performance for ground reaction forces (GRF) and lower-limb joint moments during sidestepping between ANNs fed with full-body and lower-body landmarks. 71 male college soccer athletes executed sidestepping while three-dimensional kinematics and kinetics were collected to calculate joint moments by inverse dynamic. To estimate GRF and lower-limb joint moments, coordinates of 18 full-body (the full-body landmarks ANN) and 11 lower-limb body landmarks (the lower-body landmarks ANN) were respectively used as inputs in ANNs. Estimation performance was evaluated using the coefficient of multiple correlations, root mean square error (RMSE), and normalized RMSE (nRMSE) between estimated and measured results. A Wilcoxon signed-rank test determined the difference in estimation performance between the two types of ANNs. Statistical parametric mapping determined the difference between the estimated and measured curves. The lower-body landmarks ANN showed lower error for sagittal knee moments (RMSE: p < 0.001; nRMSE: p < 0.001), but higher error for sagittal hip (RMSE: p = 0.015) and ankle moments (RMSE: p = 0.001; nRMSE: p = 0.001). Significant differences between the lower-body landmarks ANN estimates and measurement curves were found in anterior-posterior GRF (10–12 %, p = 0.013), vertical GRF (5–15 %, p < 0.001), and hip transverse moment (1 %, p = 0.017). No significant differences were found in the estimated and measured GRF peaks. The ANN only using lower-body landmarks as inputs could accurately estimate GRF and lower-limb joint moments during sidestepping, with better performance for knee moments, while ANN using full-body landmarks performs better for hip and ankle moments.

{"title":"Artificial neural networks’ estimations of lower-limb kinetics in sidestepping: Comparison of full-body vs. lower-body landmark sets","authors":"Yulin Zhou , Shengxing Fu , Tianqi Yao , Hui Liu , Hanjun Li","doi":"10.1016/j.jbiomech.2025.112548","DOIUrl":"10.1016/j.jbiomech.2025.112548","url":null,"abstract":"<div><div>Artificial neural networks (ANNs) offers potential for obtaining kinetics in non-laboratory. This study compared the estimation performance for ground reaction forces (GRF) and lower-limb joint moments during sidestepping between ANNs fed with full-body and lower-body landmarks. 71 male college soccer athletes executed sidestepping while three-dimensional kinematics and kinetics were collected to calculate joint moments by inverse dynamic. To estimate GRF and lower-limb joint moments, coordinates of 18 full-body (the full-body landmarks ANN) and 11 lower-limb body landmarks (the lower-body landmarks ANN) were respectively used as inputs in ANNs. Estimation performance was evaluated using the coefficient of multiple correlations, root mean square error (RMSE), and normalized RMSE (nRMSE) between estimated and measured results. A Wilcoxon signed-rank test determined the difference in estimation performance between the two types of ANNs. Statistical parametric mapping determined the difference between the estimated and measured curves. The lower-body landmarks ANN showed lower error for sagittal knee moments (RMSE: p < 0.001; nRMSE: p < 0.001), but higher error for sagittal hip (RMSE: p = 0.015) and ankle moments (RMSE: p = 0.001; nRMSE: p = 0.001). Significant differences between the lower-body landmarks ANN estimates and measurement curves were found in anterior-posterior GRF (10–12 %, p = 0.013), vertical GRF (5–15 %, p < 0.001), and hip transverse moment (1 %, p = 0.017). No significant differences were found in the estimated and measured GRF peaks. The ANN only using lower-body landmarks as inputs could accurately estimate GRF and lower-limb joint moments during sidestepping, with better performance for knee moments, while ANN using full-body landmarks performs better for hip and ankle moments.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"181 ","pages":"Article 112548"},"PeriodicalIF":2.4,"publicationDate":"2025-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143065899","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Lattice Models: Non-Conventional simulation methods for mechanobiology

IF 2.4 3区医学 Q3 BIOPHYSICS

Journal of biomechanics

Pub Date : 2025-01-27 DOI: 10.1016/j.jbiomech.2025.112555

Lorenzo Vaiani, Antonio Emmanuele Uva, Antonio Boccaccio

Computational methods represent a powerful tool to explore biophysical phenomena occurring at small scales and hence difficult to observe through experimental setups. In detail, they can provide a support to mechanobiology, with the aim of understanding the behavior of living cells interacting with the surrounding environment. To this end, lattice models can provide a simulation framework that is highly reliable and easy to implement, even for simulations involving large deformations and topological changes during time evolution. In this review article, elastic network models for studying biological molecules are described, several lattice spring models for investigating cell behaviors are discussed, and the adoption of lattice beam models for biomimetic structures design is presented. The lattice modelling approaches could be regarded as a valuable option to conduct in-silico experiments and consolidate the emergent mechanobiology research field.

引用次数: 0

Characterizing baseline fixed charge density in human cervical intervertebral discs

IF 2.4 3区医学 Q3 BIOPHYSICS

Journal of biomechanics

Pub Date : 2025-01-27 DOI: 10.1016/j.jbiomech.2025.112554

Nathan Buchweitz , Yi Sun , Sarah Cisewski Porto , Shangping Wang , Charles A. Reitman , Hai Yao , Yongren Wu

This study provides quantification of fixed charge density in human cervical intervertebral discs. Fixed charge density, which occurs due to negatively charged proteoglycans in the extracellular matrix, is a key determinant of the intervertebral disc osmotic environment and swelling properties. While regional fixed charge density patterns have been characterized in lumbar discs, they remain unexplored in cervical discs. Using fresh-frozen cadaveric cervical discs from five donors, fixed charge density was measured using a two-point electrical conductivity method. Glycosaminoglycan content and porosity were also assessed. Fixed charge density (0.18 ± 0.1 mEq/g wet tissue) was highest in the cartilage endplate region and significantly greater than in that in the annulus fibrosus (p = 0.006). No significant difference in fixed charge density was observed between the nucleus pulposus and annulus fibrosus. Glycosaminoglycan content (40.3 ± 14.4 µg/mg wet tissue) showed a strong positive correlation with fixed charge density across regions (r = 0.65, p = 0.0047). Unlike lumbar discs, fixed charge density was found to be more homogeneous between the nucleus pulposus and annulus fibrosus regions. This result likely reflects adaptations for reduced tissue swelling in cervical discs to accommodate lower weight-bearing demands and increased flexibility. The elevated fixed charge density in the cervical endplates may protect the intervertebral disc-vertebral bone interface, potentially to avoid mechanical damage in a kinematically more mobile environment. These findings establish key benchmarks for understanding cervical disc electro-biomechanics and may inform other cervical disc tissue-characterization efforts.

{"title":"Characterizing baseline fixed charge density in human cervical intervertebral discs","authors":"Nathan Buchweitz , Yi Sun , Sarah Cisewski Porto , Shangping Wang , Charles A. Reitman , Hai Yao , Yongren Wu","doi":"10.1016/j.jbiomech.2025.112554","DOIUrl":"10.1016/j.jbiomech.2025.112554","url":null,"abstract":"<div><div>This study provides quantification of fixed charge density in human cervical intervertebral discs. Fixed charge density, which occurs due to negatively charged proteoglycans in the extracellular matrix, is a key determinant of the intervertebral disc osmotic environment and swelling properties. While regional fixed charge density patterns have been characterized in lumbar discs, they remain unexplored in cervical discs. Using fresh-frozen cadaveric cervical discs from five donors, fixed charge density was measured using a two-point electrical conductivity method. Glycosaminoglycan content and porosity were also assessed. Fixed charge density (0.18 ± 0.1 mEq/g wet tissue) was highest in the cartilage endplate region and significantly greater than in that in the annulus fibrosus (p = 0.006). No significant difference in fixed charge density was observed between the nucleus pulposus and annulus fibrosus. Glycosaminoglycan content (40.3 ± 14.4 µg/mg wet tissue) showed a strong positive correlation with fixed charge density across regions (r = 0.65, p = 0.0047). Unlike lumbar discs, fixed charge density was found to be more homogeneous between the nucleus pulposus and annulus fibrosus regions. This result likely reflects adaptations for reduced tissue swelling in cervical discs to accommodate lower weight-bearing demands and increased flexibility. The elevated fixed charge density in the cervical endplates may protect the intervertebral disc-vertebral bone interface, potentially to avoid mechanical damage in a kinematically more mobile environment. These findings establish key benchmarks for understanding cervical disc electro-biomechanics and may inform other cervical disc tissue-characterization efforts.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"181 ","pages":"Article 112554"},"PeriodicalIF":2.4,"publicationDate":"2025-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143074472","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0