Journal of the Mechanical Behavior of Biomedical Materials最新文献_第4页

Reassessing the center of resistance in maxillary central incisors for clinical application 上颌中切牙阻力中心的重新评估及其临床应用。

IF 3.5 2区医学 Q2 ENGINEERING, BIOMEDICAL

Journal of the Mechanical Behavior of Biomedical Materials

Pub Date : 2025-12-15 DOI: 10.1016/j.jmbbm.2025.107312

Falko Schmidt, Martin Eberhard Geiger, Bernd Georg Lapatki

The center of resistance (CR) allows orthodontists to predict tooth movement (TM) in response to therapeutic load application. However, previously reported CR locations vary immensely, questioning the reliability of commonly used mean values. This study quantifies CR variability in maxillary central incisors relative to anatomical variables to improve the reliability and individualization of CR assessment.

CR locations were determined from volumetric scans of 30 teeth using nonlinear finite element analysis under clinically relevant loads. Results for various labiolingual crown inclinations (−45°–30°), expressed as vertical distance to the orthodontic bracket and relative to root height, were analyzed and compared with literature, considering load direction and methodology employed. Morphological and load variables were correlated with CR locations via linear regression, and predictor importance was assessed.

The mean vertical CR-to-bracket-center distance was 9.1 mm in Andrews’ anatomical orientation. Thirty-degree retroclination (vertical tooth long axis) and proclination yielded 11.6 mm and 4.3 mm, respectively. Morphology-driven 95 % variability was consistently around 4.4 mm. Relative to root height, CR locations were highly reference-dependent, averaging 44–55 % from the mesiodistal alveolar margin and -15–40 % from the labial margin, over the inclination range. Vertical tooth height was the dominant predictor, explaining 93 % of CR variability. Further accounting for labiolingual crown inclination reduced the 95 % prediction interval half-width to 1 mm.

A reliable CR description requires a well-defined reference frame and is best normalized by vertical tooth length. Including inclination and TM direction as predictors enables sufficiently accurate CR estimates for advanced computer-aided treatment planning and simulation.

阻力中心（CR）允许正畸医生预测牙齿运动（TM）响应治疗负荷的应用。然而，先前报道的CR位置差异很大，质疑常用平均值的可靠性。本研究量化上颌中切牙相对于解剖学变量的CR变异性，以提高CR评估的可靠性和个体化。在临床相关载荷下，利用非线性有限元分析从30颗牙齿的体积扫描确定CR位置。考虑载荷方向和所采用的方法，对不同唇舌冠倾斜度（-45°-30°）的结果进行分析，并与文献进行比较。形态学和负荷变量通过线性回归与CR位置相关，并评估预测因子的重要性。在Andrews解剖方向上，cr到支架中心的平均垂直距离为9.1 mm。30度后倾（垂直牙长轴）和前倾分别为11.6 mm和4.3 mm。形态驱动的95%变异率始终在4.4 mm左右。相对于根高度，CR的位置高度依赖于参考，在倾斜范围内，平均44- 55%来自中远端牙槽缘，-15- 40%来自唇缘。牙齿垂直高度是主要的预测因子，解释了93%的CR变异。进一步考虑唇舌冠倾斜度，将95%的预测区间半宽度降低到1mm。一个可靠的CR描述需要一个定义良好的参照系，并且最好通过垂直齿长进行规范化。包括斜度和TM方向作为预测因子，可以为先进的计算机辅助治疗计划和模拟提供足够准确的CR估计。

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引用次数: 0

Shape analysis of post-extraction needle holes in porcine skin 猪皮提取后针孔形状分析。

IF 3.5 2区医学 Q2 ENGINEERING, BIOMEDICAL

Journal of the Mechanical Behavior of Biomedical Materials

Pub Date : 2025-12-13 DOI: 10.1016/j.jmbbm.2025.107313

Marek Trączyński , Katarzyna Rosłan , Natalia Budzińska , Marcin Suszyński , Rafał Talar

Hypodermic needle injections are widely used in clinical practice, yet the detailed morphology of skin punctures remains insufficiently characterized. This study aimed to investigate how needle size, insertion depth, sample storage time, and insertion angle influence the dimensions and shape of puncture wounds. Using porcine skin as a human tissue analog, over 200 needle insertions were conducted, and punctures were quantitatively analyzed through optical profilometry. Results demonstrated that puncture dimensions were consistently smaller than the needle's nominal size, indicating the significant influence of the skin's viscoelastic properties. Deeper insertions resulted in more extensive tissue disruption, while refrigerated tissues exhibited increased deformation compared to fresh ones. Additionally, rotating the needle around its axis altered the puncture geometry, reflecting the orientation of collagen fibers beneath the skin. The article also includes images of hypodermic needle skin holes at various stages of insertion, providing visual insight into puncture formation. These findings, together with the proposed theory on puncture formation in the skin caused by hypodermic needles, offer a basis for the development of more optimized injection techniques, with potential to support creation of reference wound-shape patterns.

皮下针头注射在临床实践中被广泛使用，但皮肤穿刺的详细形态仍然缺乏充分的特征。本研究旨在探讨针头尺寸、插入深度、样本存放时间和插入角度对穿刺创面尺寸和形状的影响。以猪皮作为人体组织模拟物，进行了200多次针头插入，并通过光学轮廓术定量分析了穿刺。结果表明，穿刺尺寸始终小于针头的标称尺寸，表明皮肤的粘弹性特性的显著影响。更深的插入导致更广泛的组织破坏，而冷藏组织比新鲜组织表现出更大的变形。此外，针头绕其轴线旋转改变了穿刺的几何形状，反映了皮肤下胶原纤维的方向。文章还包括在不同的插入阶段皮下针头皮肤孔的图像，提供视觉洞察穿刺形成。这些发现，连同提出的皮下注射针头在皮肤中引起穿刺形成的理论，为开发更优化的注射技术提供了基础，有可能支持创建参考伤口形状模式。

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引用次数: 0

Corrigendum to “Corrosion-fatigue of additively manufactured Ti6Al4V” [J. Mech. Behav. Biomed. Mater. 175 107289] “增材制造Ti6Al4V的腐蚀疲劳”的勘误[J]。动力机械。Behav。生物医学。材料。175 107289]。

IF 3.5 2区医学 Q2 ENGINEERING, BIOMEDICAL

Journal of the Mechanical Behavior of Biomedical Materials

Pub Date : 2025-12-12 DOI: 10.1016/j.jmbbm.2025.107304

William W. Hogg, Mueed Jamal, Nathaniel W. Zuckschwerdt, Cohen M. Hess, Susmita Bose, Amit Bandyopadhyay

引用次数: 0

Submaximal low-strain cyclic loading induces localized inelastic deformation & diminished energy dissipation in the anterior cruciate ligament 次最大低应变循环加载引起前交叉韧带局部非弹性变形和能量耗散减弱。

IF 3.5 2区医学 Q2 ENGINEERING, BIOMEDICAL

Journal of the Mechanical Behavior of Biomedical Materials

Pub Date : 2025-12-11 DOI: 10.1016/j.jmbbm.2025.107309

Peter M. Kuetzing , Ulrich M. Scheven , Ellen M. Arruda

Submaximal loading during routine activities is an understudied contributor to evolving mechanics preceding acute Anterior Cruciate Ligament (ACL) injury. This study characterizes the history-dependent mechanical response of the anteromedial (AM) bundle of the ACL subjected to repeated submaximal low-strain cyclic loading and intermittent recovery periods. This loading regime represents early-stage behavior often referred to as preconditioning, which is important for achieving steady-state mechanics but also for understanding the onset of irreversible changes. Digital image correlation (DIC) reveals the development of localized inelastic deformation in regions corresponding to clinically observed acute ACL tears. Complementary repeated cycle-recovery (RCR) experiments reveal that inelastic deformation and normalized hysteresis follow a dual-regime pattern, with pronounced early-cycle attenuation followed by a linear-log response. These findings indicate that submaximal loading induces irreversible mechanical changes on short time scales and establishes a mechanistic link between physiological relevant load histories and increased site-specific susceptibility of the ACL.

日常活动中的亚最大负荷是急性前交叉韧带（ACL）损伤前力学演变的一个尚未得到充分研究的因素。本研究描述了前韧带（AM）束在重复的次最大低应变循环加载和间歇恢复期下的历史依赖性力学响应。这种加载状态代表了通常被称为预处理的早期行为，这对于实现稳态力学和理解不可逆变化的开始都很重要。数字图像相关（DIC）揭示了临床上观察到的急性ACL撕裂相应区域的局部非弹性变形的发展。互补重复循环恢复（RCR）实验表明，非弹性变形和归一化迟滞遵循双重模式，具有明显的早期周期衰减，然后是线性对数响应。这些研究结果表明，亚最大负荷在短时间内引起不可逆的力学变化，并在生理相关负荷历史和韧带特异性易感性增加之间建立了机制联系。

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引用次数: 0

Combined experimental and micro finite element analysis of CF/PEEK pedicle screw pullout CF/PEEK椎弓根螺钉拔出的实验与微有限元结合分析

IF 3.5 2区医学 Q2 ENGINEERING, BIOMEDICAL

Journal of the Mechanical Behavior of Biomedical Materials

Pub Date : 2025-12-10 DOI: 10.1016/j.jmbbm.2025.107307

Dominic Mischler , Matteo Frigelli , Ivan Zderic , Michael Indermaur , Patrik Wili , Amin Dolati , Philippe Zysset , Peter Varga

Purpose

Pedicle screw pull-out remains a challenge in thoracolumbar spine fixation, contributing to fixation failure. Computational simulations offer a pathway to optimize screw designs across diverse materials and bone qualities towards reducing failure rates. Non-linear explicit micro-finite element (μFE) simulation was hypothesized to accurately predict pullout forces of CF/PEEK screws, with bone volume fraction (BV/TV) influencing performance. This study aimed to validate the μFE model and assess BV/TV effects on the basis of experimental testing.

Methods

Thirteen cadaveric vertebrae were instrumented with 4.5 mm (n = 13) and 5.5 mm (n = 9) CF/PEEK screws using sample-specific 3D-printed guides. Quasi-static pullout tests were conducted and simulated using non-linear explicit μFE models based on high-resolution peripheral quantitative computed tomography (HR-pQCT). Regression analysis evaluated the relationship between BV/TV and pullout force. Correlation coefficient (R²), concordance correlation coefficient (CCC), standard error of estimate (SEE), and relative standard error (RSE) were used to assess the agreement between experimental and μFE-predicted pullout forces.

Results

The linear regression relationship between BV/TV and pullout force was significantly different for the 4.5 mm and 5.5 mm screws (p = 0.001). Ordinary least squares (OLS) regression showed significant BV/TV influence on pullout strength (p = 0.001 experimental, p < 0.001 μFE). Linear regression in log10-log10 space for experimental versus μFE forces showed strong correlation (R² = 0.931, p < 0.001), despite μFE overprediction (slope = 0.752 vs. 1:1, p < 0.001; CCC = 0.745, SEE = 428.7 N, RSE = 85.2 %).

Conclusions

The validated μFE model accurately predicted pullout strength of pedicle screw of different designs, supported by strong correlation with experimental data, despite light overprediction, potentially due to the lack of insertion damage modeling. The robust in silico framework can be used to enhance orthopedic screw designs, supporting improved fixation stability across diverse bone qualities.

目的椎弓根螺钉拔出是胸腰椎固定的难点，容易导致固定失败。计算模拟为优化不同材料和骨质量的螺钉设计提供了途径，从而降低故障率。采用非线性显式微有限元（μFE）模拟方法准确预测CF/PEEK螺钉的拔出力，骨体积分数（BV/TV）对拔出力有影响。本研究旨在验证μFE模型，并在实验测试的基础上评估BV/TV效应。方法采用样品特异性3d打印导轨，分别用4.5 mm （n = 13）和5.5 mm (n = 9) CF/PEEK螺钉固定13具尸体椎骨。采用基于高分辨率外周定量计算机断层扫描（HR-pQCT）的非线性显式μFE模型进行准静态拉拔试验并进行模拟。回归分析BV/TV与拔牙力的关系。采用相关系数（R2）、一致性相关系数（CCC）、估计标准误差（SEE）和相对标准误差（RSE）评价实验结果与μ fe预测结果的一致性。结果4.5 mm和5.5 mm螺钉的BV/TV与拔牙力的线性回归关系有显著性差异（p = 0.001）。普通最小二乘（OLS）回归显示，BV/TV对拉拔强度有显著影响（实验p = 0.001, p < 0.001 μFE）。尽管μFE预测过高（斜率= 0.752 vs. 1:1, p < 0.001; CCC = 0.745, SEE = 428.7 N, RSE = 85.2%），但实验力与μFE力在log10-log10空间的线性回归显示出很强的相关性（R2 = 0.931, p < 0.001）。结论验证的μFE模型准确预测了不同设计的椎弓根螺钉的拔出强度，与实验数据具有较强的相关性，尽管存在轻微的高估，但可能是由于缺乏插入损伤建模。坚固的硅框架可用于增强骨科螺钉设计，支持改善不同骨质量的固定稳定性。

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引用次数: 0

Mechanics of bone graft and implant choices for spino-pelvic reconstruction following combined hemipelvectomy, sacrectomy and L5 vertebrectomy 联合半骨盆切除术、骶骨切除术和L5椎体切除术后脊柱-骨盆重建的骨移植物和植入物选择力学。

IF 3.5 2区医学 Q2 ENGINEERING, BIOMEDICAL

Journal of the Mechanical Behavior of Biomedical Materials

Pub Date : 2025-12-09 DOI: 10.1016/j.jmbbm.2025.107310

Ritika Raj Menghani , Karthik Tappa , Peiyan Li , Katelyn Kevorkian , Alexander F. Mericli , Valerae O. Lewis , Justin E. Bird , Raudel Avila

Spino-pelvic reconstruction following extended hemipelvectomy is a highly complex surgical procedure with significant variability in biomechanics between patients due to differences in surgical techniques. Despite its clinical significance, experimentally identifying the key biomechanical factors that govern the integrity of the reconstructed pelvis remains challenging. To address this, we developed a multiscale computational modeling framework, ranging from 1D beam theory and 2D composite trusses to anatomically accurate 3D reconstructions, to systematically evaluate the biomechanical trade-offs of bone graft selection in spino-pelvic reconstructions. Anatomically accurate, three-dimensional finite element models, reconstructed from postoperative CT imaging, were developed to simulate stress distributions in both bone and implant components of the reconstructed pelvis under quasi-static sitting conditions, representing the postoperative recovery phase. Two key choices were systematically evaluated: bone graft selection and implant material properties. Comparative analysis of tibial, femoral, and fibular grafts demonstrates that the femoral graft provides superior mechanical performance due to its larger cross-sectional area. The tibial graft exhibits approximately twice the stress level of the femur, while the fibular graft experiences stresses nearly three times higher, indicating limited suitability for structural reconstruction. Implant material analysis reveals that titanium and stainless steel minimize stress accumulation and reduce the risk of mechanical failure, making them preferable under high-load conditions. In contrast, polymer-based implants mitigate stress shielding and may be advantageous when bone remodeling is a priority. Together, these findings offer new insight into spino-pelvic reconstruction strategies and support simulation-driven design optimization to improve future outcomes for patients undergoing these complex procedures.

延长半骨盆切除术后的脊柱-骨盆重建是一项高度复杂的手术，由于手术技术的差异，患者之间的生物力学存在显著差异。尽管具有临床意义，但通过实验确定控制重建骨盆完整性的关键生物力学因素仍然具有挑战性。为了解决这个问题，我们开发了一个多尺度计算建模框架，从1D梁理论和2D复合桁架到解剖学精确的3D重建，系统地评估骨移植选择在脊柱-骨盆重建中的生物力学权衡。基于术后CT图像重建的三维有限元模型在解剖学上精确，模拟了准静态坐姿条件下重建骨盆骨和种植体组件的应力分布，代表了术后恢复阶段。系统评估两个关键选择：骨移植选择和种植材料性能。胫骨、股骨和腓骨移植物的对比分析表明，股骨移植物由于其更大的横截面积而具有更好的机械性能。胫骨移植物的应力水平大约是股骨的两倍，而腓骨移植物的应力水平几乎是股骨的三倍，这表明结构重建的适用性有限。植入物材料分析表明，钛和不锈钢最大限度地减少了应力积累，降低了机械故障的风险，使它们更适合在高负荷条件下使用。相反，聚合物为基础的植入物减轻了应力屏蔽，当骨重塑是优先考虑时可能是有利的。总之，这些发现为脊柱-骨盆重建策略提供了新的见解，并支持模拟驱动的设计优化，以改善接受这些复杂手术的患者的未来预后。

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引用次数: 0

Hydrolytic degradation behaviour of electrospun poly(ɛ-caprolactone) filaments for biological tissue repair 电纺丝聚己内酯丝在生物组织修复中的水解降解行为。

IF 3.5 2区医学 Q2 ENGINEERING, BIOMEDICAL

Journal of the Mechanical Behavior of Biomedical Materials

Pub Date : 2025-12-08 DOI: 10.1016/j.jmbbm.2025.107308

Thales Zanetti Ferreira , Huanming Chen , Kaili Chen , Pierre-Alexis Mouthuy , Laurence Brassart

Electrospun polymeric fibres are promising materials for biomedical applications, owing to their biocompatibility, biodegradability, and ability to be assembled into a non-woven fibrous mesh. In particular, continuous filaments can be produced and subsequently assembled into multi-filament braided structures for ligament and tendon tissue repair. In these applications, characterising the evolution of the mechanical properties of the filament as it degrades is of primary importance. The role of applied mechanical loads during the degradation process also needs to be understood. In this study, we characterised the hydrolytic degradation behaviour of pre-stretched electrospun filaments made of poly(

ɛ

- caprolactone) (PCL) in buffer saline solution at 45 °C for up to 5 weeks, considering both non-loaded and loaded conditions. We show that PCL filaments degrade significantly over this relatively short time period, with non-loaded specimens showing a 21 % reduction in molecular weight after 5 weeks of exposure. Tensile loads applied during degradation further accelerate the degradation rate, with filaments subjected to a 25 g load showing a 33 % reduction in molecular weight over the same time period. Applied loads also impact the mechanical properties of the degraded specimens, causing an increase in elastic modulus and strength but a sharp decrease in elongation at break with exposure time. Our findings have implications for the design of PCL electrospun constructs in load bearing biomedical applications.

电纺丝聚合物纤维由于其生物相容性、生物可降解性和组装成无纺布纤维网的能力，在生物医学应用方面是很有前途的材料。特别是，连续细丝可以产生并随后组装成多细丝编织结构，用于韧带和肌腱组织修复。在这些应用中，表征长丝在降解过程中机械性能的演变是至关重要的。在降解过程中施加的机械载荷的作用也需要了解。在这项研究中，我们在45°C的缓冲盐水溶液中表征了预拉伸的聚（β -己内酯）（PCL）制成的静电纺丝的水解降解行为，并考虑了负载和非负载条件。我们发现PCL细丝在相对较短的时间内显著降解，未加载的样品在暴露5周后分子量减少21%。在降解过程中施加的拉伸载荷进一步加速了降解速度，在相同的时间内，受到25克载荷的长丝的分子量减少了33%。外加载荷也会影响退化试样的力学性能，导致弹性模量和强度增加，但断裂伸长率随着暴露时间的增加而急剧下降。我们的研究结果对PCL静电纺丝结构体在承载生物医学应用中的设计具有启示意义。

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引用次数: 0

Reproducibility in the morphological and mechanical properties of a natural polymer for guided bone regeneration applications 用于引导骨再生应用的天然聚合物的形态和机械性能的再现性。

IF 3.5 2区医学 Q2 ENGINEERING, BIOMEDICAL

Journal of the Mechanical Behavior of Biomedical Materials

Pub Date : 2025-12-08 DOI: 10.1016/j.jmbbm.2025.107306

Benedetta Isella , Aleksander Drinic , Alissa Heim , Hans Leemhuis , Nadja Kröger , Rene Tolba , Alexander Kopp

Dental barrier membranes play a key role in guided bone regeneration (GBR) to separate soft tissue from regenerating bone. Bioabsorbable collagen membranes, the gold standard in GBR procedures, are appealing due to elimination of the need for secondary surgeries and mechanical properties mimicking native tissue. However, challenges include rapid degradation, inconsistent reproducibility in mechanical and morphological properties, and use of animal-derived tissues. This study explored silk fibroin, a biocompatible and slowly bioabsorbable biomaterial as an alternative for GBR membranes. Silk fibroin showed comparable mechanical performance and demonstrated improved reproducibility. Two silk fibroin-based multilayered membranes (SF1 and SF2) were developed showing homogeneous appearance, density, and thickness, with lower variability than the other tested commercial options. These membranes exhibited elasto-plastic mechanical behaviour in both dry and hydrated states, supporting improved surgical handling and dimensional stability. Furthermore, elastic modulus in hydrated state (23.8 ± 3.2 MPa for SF1, 27.6 ± 3.9 MPa for SF2), burst pressure (17.5 ± 5.0 mmHg for SF1, 290.0 ± 32.6 mmHg for SF2), and force at first deformation in the suture retention strength test in hydrated state (0.10 ± 0.03 N for SF1, 0.26 ± 0.11 N for SF2) were comparable to commercial collagen membranes, suggesting the suitability for GBR applications. These findings provide a basis for further biological and preclinical characterization as well as clinical application of silk fibroin-based GBR membranes.

牙屏障膜在引导骨再生（GBR）中将软组织与再生骨分离的过程中起着关键作用。生物可吸收的胶原膜是GBR手术的金标准，由于消除了二次手术的需要和模仿天然组织的机械性能，它很有吸引力。然而，挑战包括快速降解，机械和形态特性的不一致可重复性，以及动物来源组织的使用。本研究探索了一种具有生物相容性和缓慢生物吸收性的生物材料——丝素蛋白作为GBR膜的替代材料。丝素表现出类似的机械性能，并表现出更好的再现性。两种基于丝素蛋白的多层膜（SF1和SF2）显示出均匀的外观、密度和厚度，比其他测试的商业选择具有更低的可变性。这些膜在干燥和水合状态下都表现出弹塑性力学行为，支持改进手术操作和尺寸稳定性。此外，水合状态下的弹性模量（SF1为23.8±3.2 MPa， SF2为27.6±3.9 MPa），破裂压力（SF1为17.5±5.0 mmHg， SF2为290.0±32.6 mmHg），以及水合状态下缝合保持强度测试中的首次变形力（SF1为0.10±0.03 N， SF2为0.26±0.11 N）与商用胶原膜相当，表明其适用于GBR应用。这些发现为丝素基GBR膜的进一步生物学和临床前表征以及临床应用提供了基础。

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引用次数: 0

Bioinspired auxetic metamaterial liners and sockets for transtibial prostheses: Energy absorption and stress redistribution 仿生仿生超材料衬垫和骨槽：能量吸收和应力再分配。

IF 3.5 2区医学 Q2 ENGINEERING, BIOMEDICAL

Journal of the Mechanical Behavior of Biomedical Materials

Pub Date : 2025-12-06 DOI: 10.1016/j.jmbbm.2025.107305

Mahdi Bodaghi , Saman Jolaiy , Kaveh Rahmani , Sheng Li , Fei Gao , Ali Zolfagharian

Prosthetic comfort depends on how the residual limb, liner, and socket share load. A crab-inspired auxetic metamaterial is introduced and applied to transtibial liners and sockets, with region-specific and fully auxetic variants benchmarked against conventional interfaces. Patient CT/3D scans guided anatomically targeted components. Auxetic lattices were additively manufactured in TPU (liners) and PA-12 (sockets). Cyclic compression experiments calibrated material models, and finite-element analyses quantified interface stresses and energy metrics. Across four sensitive liner regions, a four-zone auxetic TPU liner cut peak von Mises stresses by up to 60 %, and a fully auxetic liner by up to 65 %, relative to silicone/EL50 baselines. In sockets, a PA-12 design with two auxetic zones reduced peak stresses by ∼40–45 % versus ABS, while a fully auxetic socket achieved ∼80 % reductions with higher specific energy absorption. These findings indicate that bioinspired auxetics, integrated where anatomy needs compliance, improve pressure redistribution and mass-efficient energy management. The workflow from imaging to lattice design, printing, testing, and simulation was validated and is compatible with multi-jet fusion, enabling patient-specific prosthetic interfaces suitable for clinical translation.

假肢的舒适性取决于残肢、衬垫和关节窝如何分担负荷。一种受螃蟹启发的补足超材料被引入并应用于跨骨衬垫和插座，具有特定区域和完全补足的变体，对传统接口进行基准测试。患者CT/3D扫描引导解剖目标部件。在TPU（衬垫）和PA-12（插座）中增材制造辅助晶格。循环压缩实验校准了材料模型，有限元分析量化了界面应力和能量指标。相对于硅胶/EL50基线，在四个敏感衬管区域，四区auxetic TPU衬管可将峰值von Mises应力降低60%，而完全auxetic衬管可将峰值von Mises应力降低65%。在插座中，与ABS相比，具有两个辅助区的PA-12设计可将峰值应力降低约40- 45%，而完全辅助的插座具有更高的比能吸收，可将峰值应力降低约80%。这些发现表明，在解剖学需要顺应性的地方，结合生物启发的辅助疗法可以改善压力再分配和质量效率的能量管理。从成像到格子设计、打印、测试和模拟的工作流程经过验证，并与多射流融合兼容，使患者特定的假肢接口适合临床翻译。

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引用次数: 0

Biomechanical evaluation of load transfer in Talus focal resurfacing implant: experimental and finite element models 距骨局部表面植入物载荷转移的生物力学评估：实验和有限元模型。

IF 3.5 2区医学 Q2 ENGINEERING, BIOMEDICAL

Journal of the Mechanical Behavior of Biomedical Materials

Pub Date : 2025-12-04 DOI: 10.1016/j.jmbbm.2025.107300

A. Ramos, M. Vieira

Introduction

Osteochondral lesions (OTLs) are common injuries in ankle sprains, occurring in up to 70 % of patients. Recovery options are limited due to the talus bone's poor vascularization. This study aimed to develop a computational model of an ankle joint to evaluate cartilage stress in the presence of an OTL and assess the biomechanical effectiveness of a focal resurfacing prosthesis in reducing joint stress.

Materials and methods

Both in silico and physical model models were developed based on a previous case study involving a patient with a medial OTL in the right ankle. A 10 mm diameter focal resurfacing prosthesis was tested in two positions: proud (+0.5 mm) and recessed (−0.5 mm), as recommended in clinical guidelines. Cartilage stress and trabecular bone strain in the talus were evaluated. The in vitro model, produced via additive manufacturing and instrumented with strain gauges, was used to validate the finite element (FE) model by comparing measured and simulated strains.

Results

The FE model showed strong agreement with experimental data, with a correlation coefficient of 0.88. Both the lesion and prosthesis placement influenced talar cartilage stress. The OTL increased stress by approximately 23 % near the lesion site and 8 % in more distal regions. The highest cartilage stress (7.20 MPa) occurred with the prosthesis in the recessed position. Prosthesis positioning significantly affected cartilage stress distribution (p < 0.001).

Conclusions

While fixation of the focal prosthesis remains challenging, placing it slightly proud can help reduce stress on talar cartilage. However, excessive proud positioning increases stress on tibial cartilage and should be avoided. Proper prosthesis placement is critical for optimal stress reduction. Furthermore, fixation in the talus reduces trabecular bone strain, potentially mitigating bone loss and enhancing implant stability.

骨软骨病变（OTLs）是踝关节扭伤中常见的损伤，发生率高达70%。由于距骨血管化不良，恢复选择有限。本研究旨在建立一个踝关节的计算模型，以评估踝关节外翻时的软骨应力，并评估局部表面置换假体在减轻关节应力方面的生物力学有效性。材料和方法：计算机模型和物理模型都是基于先前的案例研究开发的，该案例研究涉及一名右脚踝内侧外伤性损伤的患者。按照临床指南的建议，在两个位置测试直径为10mm的局部表面修复体：骄傲（+0.5 mm）和凹陷（-0.5 mm）。评估距骨软骨应力和骨小梁应变。通过增材制造和应变仪制作的体外模型，通过比较实测应变和模拟应变来验证有限元（FE）模型。结果：有限元模型与实验数据吻合较好，相关系数为0.88。损伤和假体放置对距骨软骨应力均有影响。OTL使损伤部位附近的应力增加约23%，远端区域的应力增加约8%。假体处于凹位时，软骨应力最大（7.20 MPa）。假体定位显著影响软骨应力分布(p)结论：虽然局灶性假体的固定仍然具有挑战性，但将假体略微抬高有助于减少距骨软骨的应力。然而，过度骄傲的定位会增加胫骨软骨的压力，应该避免。适当的假体放置是最佳的应力减少的关键。此外，距骨内固定可减少骨小梁应变，潜在地减轻骨丢失并增强植入物的稳定性。

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