Journal of biomechanics最新文献_第3页

Effects of combined active knee exercise and high-intensity continuous ultrasound on infrapatellar fat pad stiffness and gliding in healthy participants: A randomised, single-blind, placebo-controlled crossover trial 联合积极膝关节运动和高强度连续超声对健康参与者髌下脂肪垫硬度和滑动的影响：一项随机、单盲、安慰剂对照交叉试验

IF 2.4 3区医学 Q3 BIOPHYSICS

Journal of biomechanics

Pub Date : 2026-01-29 DOI: 10.1016/j.jbiomech.2026.113191

Naoto Ikeda , Taizan Fukaya , Yui Sezaki , Sho Toyoshima , Yukiho Ichikawa , Yuka Yokoi , Katsuyuki Morishita

Reduced flexibility of the infrapatellar fat pad (IFP) contributes to anterior knee pain. High-intensity continuous ultrasound (HICUS) decreases IFP stiffness and improves gliding. However, the effect of combining exercise therapy with HICUS remains unclear. We conducted a randomised, single-blind, placebo-controlled crossover trial involving 20 healthy participants to evaluate the effects of combined active knee exercise and HICUS on IFP stiffness and gliding. Healthy participants received active knee exercise with HICUS and sham HICUS on separate days. HICUS was applied at 1 MHz, 2.5 W/cm², 100% duty cycle for 5 min using an ultrasound unit with automatic rotation. The main outcomes were IFP stiffness at 10° and 120° knee flexion and IFP gliding. Measurements were taken before (T1), immediately after (T2), and 15 min after (T3) ultrasound irradiation. IFP stiffness at 10° knee flexion decreased from T1 (13.6 ± 1.7) to T2 (9.4 ± 0.8) under HICUS conditions. At 120° knee flexion, IFP stiffness decreased from T1 (57.5 ± 12.8) to T2 (31.6 ± 6.5) and T3 (36.8 ± 12.1) under HICUS conditions. IFP gliding improved from T1 (29.6 ± 1.3) to T2 (34.7 ± 1.3) and T3 (32.8 ± 1.4) under HICUS conditions and from T1 (29.2 ± 1.5) to T2 (30.9 ± 1.2) under placebo conditions. These findings suggest that combined active knee exercise and HICUS is a safe, effective short-term intervention to reduce IFP stiffness and improve gliding. Further studies involving patients with knee osteoarthritis are needed to validate its clinical applicability.

髌下脂肪垫（IFP）柔韧性降低导致膝关节前侧疼痛。高强度连续超声（HICUS）降低IFP刚度，改善滑动。然而，运动疗法与HICUS联合治疗的效果尚不清楚。我们进行了一项随机、单盲、安慰剂对照的交叉试验，涉及20名健康参与者，以评估联合主动膝关节运动和HICUS对IFP僵硬和滑动的影响。健康的参与者分别在不同的日子接受HICUS和假HICUS的积极膝关节运动。使用自动旋转的超声装置，在1 MHz， 2.5 W/cm2, 100%占空比下应用HICUS 5分钟。主要结果是膝关节屈曲10°和120°时IFP僵硬和IFP滑动。分别于超声照射前（T1）、照射后（T2）和照射后15分钟（T3）进行测量。在HICUS条件下，膝关节屈曲10°时IFP刚度从T1（13.6±1.7）降至T2（9.4±0.8）。当膝关节屈曲120°时，HICUS条件下IFP刚度从T1（57.5±12.8）降至T2（31.6±6.5）和T3（36.8±12.1）。HICUS组IFP滑行从T1（29.6±1.3）改善到T2（34.7±1.3）和T3(32.8±1.4)，安慰剂组从T1（29.2±1.5）改善到T2（30.9±1.2）。这些研究结果表明，膝关节主动运动联合HICUS是一种安全、有效的短期干预措施，可降低IFP僵硬度并改善滑动。需要对膝关节骨性关节炎患者进行进一步的研究来验证其临床适用性。

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引用次数: 0

Examination of inertial measurement units to evaluate lower body segmental angles in persons with autism 用惯性测量装置评估自闭症患者下体节段角。

IF 2.4 3区医学 Q3 BIOPHYSICS

Journal of biomechanics

Pub Date : 2026-01-22 DOI: 10.1016/j.jbiomech.2026.113172

Lauren A. Luginsland , Kiara B. Barrett , Hunter J. Bennett

Inertial measurement units (IMU’s) have been used to collect human movement data in practical, real-world environments in both non-pathological and pathological gait. IMU sensors have produced strong results for their validity and repeatability compared to the gold-standard of motion capture, specifically in college-aged populations. Due to their small size and lightweight design, IMU’s can be very convenient for the collection of movement data across various populations. Given the unique movement patterns reported in persons with autism (i.e., variability both intra- and inter-subject), the purpose of this proposed study was to compare gait events and segmental angles of the foot, shank, and thigh during gait via IMU’s compared to the “gold standard” of motion capture. Gait events were calculated using the superior-inferior acceleration/anterior-posterior acceleration (SIacc/APacc) methodology and the 10 N vertical ground reaction force (vGRF) methodology. Gait event detection was matched between SIacc/APacc and vGRF methods for heel strike yet significantly different for toe off. Our results support the existing literature suggesting an agreement in sagittal plane lower extremity segmental angles between IMU’s and motion capture, with less agreement between modalities in the frontal and transverse planes. However, these findings should be approached with caution and accompanied by recommendations that take into account the attributes of each participant (e.g. stimming, sensitivities). Future work investigating specific functional tasks to define the axis system and limit out-of-plane motion is needed in this population.

惯性测量单元（IMU）已被用于在实际的、真实的环境中以非病理和病理步态收集人体运动数据。与运动捕捉的黄金标准相比，IMU传感器的有效性和可重复性已经产生了强有力的结果，特别是在大学年龄的人群中。由于IMU的小尺寸和轻量化设计，它可以非常方便地收集不同人群的运动数据。鉴于自闭症患者报告的独特运动模式（即受试者内部和受试者之间的可变性），本研究的目的是通过IMU比较步态过程中足、小腿和大腿的节段角度和运动捕捉的“黄金标准”。采用上下加速度/前后加速度（SIacc/APacc）方法和10 N垂直地面反作用力（vGRF）方法计算步态事件。SIacc/APacc与vGRF方法对足跟撞击的步态事件检测结果相匹配，但对脱趾的步态事件检测结果存在显著差异。我们的研究结果支持了现有文献的观点，即IMU和运动捕捉在矢状面下肢节段角度上是一致的，而在额平面和横平面上的模式不太一致。然而，这些发现应该谨慎对待，并伴随着考虑到每个参与者的属性（例如刺激，敏感性）的建议。未来的工作需要研究特定的功能任务来定义轴系统和限制面外运动。

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引用次数: 0

Therapeutic potential of a supine straight-leg thrust in managing knee joint dysfunction in knee osteoarthritis: A biomechanical study 仰卧直腿推力治疗膝关节骨性关节炎的治疗潜力：一项生物力学研究

IF 2.4 3区医学 Q3 BIOPHYSICS

Journal of biomechanics

Pub Date : 2026-01-22 DOI: 10.1016/j.jbiomech.2026.113183

Xiaolong Zeng , Shiyang Chen , Qingyang Kang , Wenjia Zhou , Zhilin Ge , Ruotong Liao , Xin Zhang , Shunying Huang , Guoyi Su , Fangzheng Lin , Yongjin Li , Dingkun Lin

Rehabilitation of knee osteoarthritis is often constrained by limited understanding of muscle activation patterns and active joint mobilization mechanisms. The supine straight-leg thrust (SST) exercise, previously introduced by our team, has shown promising clinical effects, yet its neuromuscular and kinematic mechanisms remain unclear. This study aims to investigate quadriceps-hamstring activation and knee joint kinematics during SST using synchronized surface electromyography and three-dimensional motion capture, and to compare its biomechanical effects with walking, squatting, and supine air cycling (SAC).

Fifteen healthy adults performed walking, squatting, SST, and SAC exercises. Surface electromyography data of the quadriceps and hamstrings, and three-dimensional kinematic data of the tibiofemoral and patellofemoral joints were collected. Comparisons were made across tasks to evaluate muscle activation levels and multi-planar joint range of motion.

SST elicited significantly greater activation of the rectus femoris, vastus medialis, and vastus lateralis compared to walking (P < 0.05), with levels comparable to squatting. SST also produced significantly larger ranges of motion in both tibiofemoral and patellofemoral joints than walking and squatting (P < 0.05). Compared to SAC, SST resulted in higher thigh muscle activation and more favorable joint mobility (P < 0.05).

SST effectively activates key quadriceps muscles and enhances multi-planar knee joint mobility, outperforming walking, squatting, and SAC. These findings support the biomechanical rationale for SST as a targeted exercise for addressing joint dysfunction in knee osteoarthritis rehabilitation.

膝关节骨性关节炎的康复常常受到肌肉激活模式和主动关节动员机制的有限理解的限制。我们团队之前介绍的仰卧直腿推力（SST）运动已经显示出有希望的临床效果，但其神经肌肉和运动学机制尚不清楚。本研究旨在利用同步体表肌电图和三维运动捕捉研究SST期间股四头肌-腿筋的激活和膝关节运动学，并比较其与步行、深蹲和仰卧空气循环（SAC）的生物力学效果。15名健康成人进行了步行、下蹲、SST和SAC锻炼。收集股四头肌和腘绳肌的表面肌电图数据，以及胫股关节和髌股关节的三维运动学数据。对不同任务进行比较，以评估肌肉激活水平和多平面关节运动范围。与步行相比，SST引起股直肌、股内侧肌和股外侧肌明显更大的激活（P < 0.05），其水平与深蹲相当。SST在胫股关节和髌股关节的活动范围也明显大于步行和深蹲（P < 0.05）。与SAC相比，SST导致更高的大腿肌肉激活和更有利的关节活动（P < 0.05）。SST有效激活关键的股四头肌，增强膝关节多平面活动能力，优于步行、深蹲和SAC。这些发现支持了SST作为解决膝关节骨关节炎康复中关节功能障碍的目标运动的生物力学原理。

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引用次数: 0

Non-pharmacological modulation of aortic hemodynamic condition by extreme heat 极端高温对主动脉血流动力学状况的非药物调节

IF 2.4 3区医学 Q3 BIOPHYSICS

Journal of biomechanics

Pub Date : 2026-01-20 DOI: 10.1016/j.jbiomech.2026.113175

Jiyang Zhang , Lingjun Liu , Wentao Jiang , Ming Zhang , Taoping Bai , Yu Chen , Fei Gao , Zhongyou Li

Extreme heat exposure is a promising non-pharmacological strategy for cardiovascular health, yet its underlying hemodynamic mechanisms remain poorly understood. Here, computational fluid dynamics (CFD) was used to assess heat-induced changes in aortic blood flow. Three-dimensional aortic geometries were reconstructed from computed tomography scans of six healthy adults (mean age: 50.8 ± 12.8 years). Inlet conditions were adjusted to simulate thermal stress (80–100 °C) based on reported increases in cardiac output (67%) and heart rate (33%), whereas outlet boundaries were modeled using Windkessel elements with parameters tuned for flow redistribution. The effects of vascular deformation were accounted for using a fluid–structure interaction approach. Key hemodynamic metrics, including time-averaged wall shear stress (TAWSS), oscillatory shear index (OSI), relative residence time (RRT), and endothelial cell activation potential (ECAP), were quantified before and after heat exposure. In parallel, 12 rats were randomly assigned to a heat-exposed group (n = 6; 41 °C, 20 min) or a control group (n = 6; 24 °C, 20 min), after which the abdominal aorta was harvested for immunofluorescence analysis of eNOS expression. Wall shear stress increased by at least 89.9% throughout the aorta and across the cardiac cycle, with the greatest increase observed at the aortic arch. TAWSS exhibited an inverse “S”-shaped spatial distribution, with regions of higher baseline shear showing greater amplification. In contrast, OSI and RRT decreased during heat exposure. On average, TAWSS rose by 108.5%, whereas OSI and RRT fell by 22.5% and 56.5%, respectively. eNOS expression in rat aortas was significantly higher in the heat-exposed group than in the control group (P < 0.05). Additionally, ECAP decreased by 57.1% during heat exposure. These results demonstrate that heat exposure significantly enhances aortic hemodynamics and may serve as a non-pharmacological strategy to improve arterial function, offering a potential alternative for individuals unable to exercise.

极端热暴露是一种很有前途的心血管健康非药物策略，但其潜在的血流动力学机制仍然知之甚少。在这里，计算流体动力学（CFD）被用于评估热引起的主动脉血流变化。通过计算机断层扫描重建6例健康成人（平均年龄：50.8±12.8岁）的主动脉三维几何形状。根据报告的心输出量（67%）和心率（33%）的增加，调整进口条件以模拟热应力（80-100°C），而出口边界则使用Windkessel元件建模，并对参数进行了调整以进行流动再分配。血管变形的影响是用流固相互作用的方法来解释的。对热暴露前后的关键血流动力学指标，包括时间平均壁剪切应力（TAWSS）、振荡剪切指数（OSI）、相对停留时间（RRT）和内皮细胞激活电位（ECAP）进行量化。同时，将12只大鼠随机分为热暴露组（n = 6; 41°C, 20 min）和对照组（n = 6; 24°C, 20 min），热暴露后取腹主动脉进行eNOS表达的免疫荧光分析。在整个主动脉和整个心脏周期中，壁剪切应力增加了至少89.9%，主动脉弓处的增幅最大。TAWSS呈反“S”型空间分布，基线切变越高的区域放大越大。相比之下，OSI和RRT在热暴露期间下降。平均而言，TAWSS上升108.5%，而OSI和RRT分别下降22.5%和56.5%。热暴露组大鼠主动脉中eNOS表达显著高于对照组（P < 0.05）。此外，在热暴露期间，ECAP下降了57.1%。这些结果表明，热暴露可以显著增强主动脉血流动力学，并可能作为一种非药物策略来改善动脉功能，为无法运动的个体提供潜在的替代方案。

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引用次数: 0

Effects of intrinsic foot muscle training on shank, rearfoot and forefoot coordination and its variability in male runners with non-rearfoot strike pattern: A randomized controlled trial 内在足部肌肉训练对男性非后脚击球模式跑步者小腿、后脚和前脚协调及其可变性的影响：一项随机对照试验

IF 2.4 3区医学 Q3 BIOPHYSICS

Journal of biomechanics

Pub Date : 2026-01-20 DOI: 10.1016/j.jbiomech.2026.113171

Zhen Wei , Shuo Qi , Zhiqiang Liang , Yan Zhao , Lin Wang

The aim of this study was to investigate the effects of intrinsic foot muscle (IFM) training on shank, rearfoot and forefoot coordination and its variability in male runners with non-rearfoot strike (NRFS) pattern. The study randomly assigned 40 habitual NRFS male runners into intervention and control groups. The participants in the intervention group received eight weeks of strength training targeting IFMs. After eight weeks of IFM training, the intervention group exhibited a substantial increase in the proportion of anti-phase coordination patterns in frontal rearfoot–transverse shank (FRTS) and frontal rearfoot–sagittal forefoot (FRSF) during early stance and a reduction in coordination variability across different phases of stance. Compared with the control group, the intervention group exhibited increased anti-phase of distal dominancy in FRTS (mid stance) and FRSF (late stance) and decreased anti-phase of distal dominancy (mid stance) in frontal rearfoot–transverse forefoot (FRTF). Moreover, the intervention group showed reduced coordination variability in frontal rearfoot–frontal forefoot (early and late stance) and FRTF (early stance). This study demonstrated that eight weeks of IFM training can improve adaptive movement strategies and enhance neuromuscular control among the shank, rearfoot, and forefoot. NRFS runners could adopt IFM training for performance optimization and injury prevention.

本研究的目的是探讨内在足肌（IFM）训练对男性非后脚打击（NRFS）模式跑步者小腿、后脚和前脚协调的影响及其变异性。该研究将40名习惯性NRFS男性跑步者随机分为干预组和对照组。干预组的参与者接受了为期8周的针对ifm的力量训练。经过8周的IFM训练后，干预组在站立早期表现出额后足-横胫（FRTS）和额后足-矢状前足（FRSF）反相位协调模式的比例显著增加，并且在不同的站立阶段协调变异性减少。与对照组相比，干预组中位前足（FRTS）和后位前足（FRSF）的远端优势反相位增加，中位前足（FRTF）的远端优势反相位降低。此外，干预组显示额后脚-额前足（早期和晚期站立）和FRTF（早期站立）的协调性变异性降低。这项研究表明，8周的IFM训练可以改善适应性运动策略，增强小腿、后脚和前脚之间的神经肌肉控制。NRFS跑者可以采用IFM训练来优化成绩和预防损伤。

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引用次数: 0

Biomechanical stability and pedicle screw loosening 生物力学稳定性和椎弓根螺钉松动

IF 2.4 3区医学 Q3 BIOPHYSICS

Journal of biomechanics

Pub Date : 2026-01-20 DOI: 10.1016/j.jbiomech.2026.113174

Chenxi Cui, Haisheng Yang

Pedicle screws are widely utilized in spinal surgeries, yet postoperative loosening remains a major complication in clinical practice. A better understanding of the screw loosening mechanisms will aid the development of proper approaches to predict screw loosening and to reduce the loosening rate. From a unique perspective of biomechanical stability, this review is motivated to provide insights into the mechanisms of pedicle screw loosening, methods to predict screw loosening risk, and strategies to reduce screw loosening risk. The biomechanical stability of screw includes primary stability and secondary stability, which are closely associated with screw loosening and affected by multiple factors, such as bone mineral density, screw parameters, osseointegration, and stress shielding. To assess the risk of pedicle screw loosening, radiographic evaluation and several in vivo (e.g., acoustic modal analysis and resonance frequency analysis), in vitro (e.g., biomechanical testing), and in silico (e.g., finite element analysis) approaches are available. Regarding the strategies to reduce the screw loosening rate, advancements in screw material, surface modification, structural design, and bone cement augmentation have demonstrated promising potential, while optimization of preoperative planning as well as robot- and augmented reality-assisted surgical techniques have significantly improved the implantation accuracy. It can be found that current research has achieved notable progress in improving the primary biomechanical stability of the pedicle screw. However, how to enhance the mechanobiological osseointegration of the bone-screw interface to achieve an improved secondary biomechanical stability for the screws, ultimately reducing the risk of long-term screw loosening, remains a question requiring further studies.

椎弓根螺钉广泛应用于脊柱手术，但术后松动仍然是临床实践中的主要并发症。更好地了解螺钉松动机制将有助于制定正确的方法来预测螺钉松动并降低松动率。从生物力学稳定性的独特角度出发，本综述旨在深入探讨椎弓根螺钉松动的机制、预测螺钉松动风险的方法以及降低螺钉松动风险的策略。螺钉的生物力学稳定性包括初级稳定性和次级稳定性，其与螺钉松动密切相关，并受到骨密度、螺钉参数、骨整合、应力屏蔽等多种因素的影响。为了评估椎弓根螺钉松动的风险，可以使用影像学评估和几种体内（例如，声学模态分析和共振频率分析）、体外（例如，生物力学测试）和计算机（例如，有限元分析）方法。在降低螺钉松动率的策略方面，螺钉材料、表面改性、结构设计和骨水泥增强技术的进步显示出良好的潜力，而术前计划的优化以及机器人和增强现实辅助手术技术显著提高了植入精度。可以发现，目前的研究在提高椎弓根螺钉的初级生物力学稳定性方面取得了显著进展。然而，如何增强骨-螺钉界面的力学生物学骨整合，以提高螺钉的二级生物力学稳定性，最终降低螺钉长期松动的风险，仍然是一个需要进一步研究的问题。

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引用次数: 0

Decoding the mechanical language of the tumor microenvironment: From physical forces to malignant behaviors 解读肿瘤微环境的机械语言：从物理力量到恶性行为

IF 2.4 3区医学 Q3 BIOPHYSICS

Journal of biomechanics

Pub Date : 2026-01-20 DOI: 10.1016/j.jbiomech.2026.113170

Luyao Zhao , Yifan Han , Jing Du , Xinbin Zhao

Malignant metastasis, the leading cause of cancer mortality, is initiated by tumor invasion, a process intrinsically linked to dynamic biomechanical alterations within the tumor microenvironment (TME). While recent reviews have established the role of extracellular matrix (ECM) stiffness, this review offers a distinct synthesis by focusing on the synergistic interplay between two critical, yet underappreciated, mechanical forces: solid stress and fluid pressure. We propose that these forces form an integrated mechanical barrier that actively promotes malignancy. As tumors grow, ECM deposition and spatial confinement generate substantial solid stress, while vascular dysfunction elevates fluid stress. This review uniquely details how this solid–fluid stress nexus drives malignant progression, immune suppression, and therapeutic resistance through coordinated mechanobiological signaling. We comprehensively synthesize how these altered forces regulate tumor cell behavior by focusing on mechanotransduction—the conversion of mechanical cues into biochemical signals. Finally, we outline a framework for novel therapeutic strategies that target this “physical barrier”, with the goal of improving drug delivery, overcoming resistance, and advancing cancer treatment.

恶性转移是癌症死亡的主要原因，是由肿瘤侵袭引发的，这一过程与肿瘤微环境（TME）内动态生物力学改变有着内在的联系。虽然最近的综述已经确定了细胞外基质（ECM）刚度的作用，但这篇综述通过关注两个关键但未被重视的机械力：固体应力和流体压力之间的协同相互作用，提供了一个独特的综合。我们认为这些力量形成一个综合的机械屏障，积极促进恶性肿瘤。随着肿瘤的生长，ECM沉积和空间限制会产生大量的固体应力，而血管功能障碍会增加液体应力。这篇综述独特地详细介绍了这种固体-流体应力联系如何通过协调的机械生物学信号驱动恶性进展、免疫抑制和治疗耐药性。我们通过关注机械转导——将机械信号转化为生化信号——全面地综合了这些改变的力是如何调节肿瘤细胞行为的。最后，我们概述了针对这一“物理屏障”的新型治疗策略框架，目标是改善药物输送，克服耐药性，推进癌症治疗。

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引用次数: 0

Mechanical effects of different cast immobilization positions in Colles’ fracture: a finite element analysis investigation 不同固定位置对Colles骨折力学影响的有限元分析研究。

IF 2.4 3区医学 Q3 BIOPHYSICS

Journal of biomechanics

Pub Date : 2026-01-17 DOI: 10.1016/j.jbiomech.2026.113167

Tatsuki Kobayashi , Takahiro Yamazaki , Yusuke Matsuura , Aya Kanazuka , Seiji Ohtori , Takane Suzuki

This study investigated the optimal cast immobilization position for conservative treatment of Colles’ fracture using finite element analysis (FEA). Ten upper limbs from cadavers were scanned with computed tomography in five palmar-dorsiflexion positions (V30, V15, DV0, D15, and D30) and five radioulnar deviation positions (U20, U10, RU0, R10, and R20). Colles’ fracture models with comminuted dorsal cortex and intact volar cortical continuity were developed and subjected to FEA. Each position was assessed for fragment displacement, principal strain at the fracture site, and equivalent stress propagation direction. The minimum fragment displacement was observed at 15° of dorsiflexion and 10° of radial deviation. The differences in distance between dorsal fragments before and after loading in V30, V15, DV0, D15, and D30 were 1.05 ± 0.25, 0.77 ± 0.23, 0.50 ± 0.18, 0.23 ± 0.18, and 0.24 ± 0.11 mm, respectively, with D15 being the smallest. Translation of volar cortical bone in U20, U10, RU0, R10, and R20 was 1.84 ± 1.06, 1.57 ± 0.80, 0.76 ± 0.67, 0.34 ± 0.15, and 0.47 ± 0.24 mm, respectively, with R10 being the smallest. Principal strains at the fracture site were minimal at D15 and R10. Stress propagation analysis revealed that forces were transmitted through the volar cortex at D15 and perpendicular to the fracture line at R10. The FEA demonstrates that cast immobilization at 15° of dorsiflexion and 10° of radial deviation is optimal for conservative treatment of Colles’ fracture by minimizing mechanical load at the fracture site.

本研究应用有限元分析（FEA）探讨保守治疗Colles骨折的最佳固定位置。对10具尸体上肢进行5个掌背屈位（V30、V15、DV0、D15和D30）和5个尺桡偏位（U20、U10、RU0、R10和R20）的计算机断层扫描。建立背皮质粉碎性和掌侧皮质连续性完整的Colles骨折模型并进行有限元分析。评估每个位置的碎片位移、断裂部位的主应变和等效应力传播方向。在背屈15°和径向偏离10°时观察到最小碎片位移。V30、V15、DV0、D15、D30加载前后背片距离差异分别为1.05±0.25、0.77±0.23、0.50±0.18、0.23±0.18、0.24±0.11 mm，其中D15最小。U20、U10、RU0、R10、R20的掌侧皮质骨平移量分别为1.84±1.06、1.57±0.80、0.76±0.67、0.34±0.15、0.47±0.24 mm，其中R10最小。断裂部位的主应变在D15和R10时最小。应力传播分析显示，力在D15处通过掌侧皮质传递，在R10处垂直于骨折线。有限元分析表明，在保守治疗Colles骨折时，以15°背屈和10°径向偏为最佳固定方式，使骨折部位的机械载荷最小。

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引用次数: 0

Comparative tensile properties of the equine vagina, penile sheath, and scrotum 马阴道、阴茎鞘和阴囊的拉伸性能比较

IF 2.4 3区医学 Q3 BIOPHYSICS

Journal of biomechanics

Pub Date : 2026-01-16 DOI: 10.1016/j.jbiomech.2026.113169

Angel E. Collins , Jennifer S. Wayne , Cecile A. Ferrando , Raffaella De Vita

This experimental study characterizes the elastic behavior of male and female equine genital tissues using uniaxial tensile testing, with strain measurements obtained via digital image correlation. Dog-bone-shaped tissue specimens were excised from mares and geldings (

n = 23

from female specimens and

n = 42

from male specimens) with all specimens aligned along the circumferential direction (CD) of the vagina, penis, and scrotum. The results include load-displacement data, stress–strain data, and tangent moduli for the penile sheath, vaginal canal, and scrotum, with strain measured in both the CD and the longitudinal direction (LD). Findings indicate that vaginal and scrotal tissues exhibit comparable mechanical properties (tangent moduli: 10.16

\pm

1.30 MPa for the vagina and 4.81

\pm

1.66 MPa for the scrotum), whereas the penile sheath (tangent modulus: 2.30

\pm

1.43 MPa) differs significantly from the vaginal and scrotal tissues (

p < 0.01

and

p < 0.05

, respectively). This mechanical evaluation of vaginal, penile, and scrotal tissues has implications for advancing surgical techniques, developing genital prostheses, and informing biomechanical models of the pelvic region.

本实验研究利用单轴拉伸测试，通过数字图像相关获得应变测量，表征了雄性和雌性马生殖器组织的弹性行为。从母马和阉马（雌性标本n=23，雄性标本n=42）中切除犬骨状组织标本，所有标本沿阴道、阴茎和阴囊的圆周方向排列。结果包括阴茎鞘、阴道管和阴囊的载荷-位移数据、应力-应变数据和切模量，并测量了CD和纵向（LD）的应变。结果表明，阴道和阴囊组织具有相似的力学性能（阴道的切线模量为10.16±1.30 MPa，阴囊的切线模量为4.81±1.66 MPa），而阴茎鞘的切线模量为2.30±1.43 MPa，与阴道和阴囊组织有显著差异（分别为0.01和0.05）。阴道、阴茎和阴囊组织的力学评估对外科技术的进步、生殖器假体的发展以及骨盆区域的生物力学模型具有重要意义。

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引用次数: 0

Accuracy of glenohumeral joint center of rotation estimates using traditional motion capture versus bi-plane fluoroscopy 使用传统运动捕捉与双平面透视评估盂肱关节旋转中心的准确性

IF 2.4 3区医学 Q3 BIOPHYSICS

Journal of biomechanics

Pub Date : 2026-01-13 DOI: 10.1016/j.jbiomech.2026.113168

Julia A. Dunn, Ola Alsaadi, Kevin Shelburne, Michelle B. Sabick

Accurate estimation of the glenohumeral joint center of rotation is critical for biomechanical modeling of shoulder motion. This study evaluated the accuracy of three predictive methods for estimating glenohumeral joint center of rotation using optical motion capture, compared against a benchmark derived from synchronous bi-plane fluoroscopy. Five healthy adults performed shoulder abduction, flexion, and external rotation in 90° abducted and adducted positions. Root mean square error and axial errors were calculated across the full range of motion. Results showed that none of the predictive methods met clinically acceptable thresholds, with absolute error exceeding 10 mm and axial errors surpassing ±5 mm. Error increased significantly with humeral elevation beyond 60° but remained stable during rotational movements. The inclusion of technical markers slightly reduced axial error but did not substantially improve overall accuracy, likely due to soft tissue artifact. Directional axial errors revealed consistent biases, with the acromion method tending to produce anterior, medial, and superior errors. These findings suggest that predictive methods may be suitable for low-elevation tasks, such as gait, but are unreliable for high-elevation activities like overhead sports. The study highlights the importance of evaluating center of rotation estimation across full motion ranges and suggests that future work should explore humeral marker placement and functional methods to mitigate soft tissue artifact and improve accuracy. Validating reliable optical motion capture-based methods against bi-plane fluoroscopy will enhance consistency and comparability in shoulder biomechanics research.

肩关节旋转中心的准确估计对于肩部运动的生物力学建模至关重要。本研究评估了使用光学运动捕捉估计盂肱关节旋转中心的三种预测方法的准确性，并与同步双平面透视得出的基准进行了比较。5名健康成人在90°外展和内收位置进行肩部外展、屈曲和外旋。在整个运动范围内计算均方根误差和轴向误差。结果显示，没有一种预测方法达到临床可接受的阈值，绝对误差超过10 mm，轴向误差超过±5 mm。当肱骨抬高超过60°时，误差显著增加，但在旋转运动中保持稳定。技术标记的加入略微减少了轴向误差，但并没有显著提高总体精度，这可能是由于软组织伪影。定向轴向误差显示出一致的偏差，肩峰法倾向于产生前、中、上部误差。这些发现表明，预测方法可能适用于低海拔的任务，如步态，但不太适用于高海拔的活动，如头顶运动。该研究强调了在全运动范围内评估旋转中心估计的重要性，并建议未来的工作应探索肱骨标记物的放置和功能方法，以减轻软组织伪影并提高准确性。验证可靠的基于光学运动捕捉的方法对抗双平面透视将增强肩膀生物力学研究的一致性和可比性。

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