Journal of biomechanics最新文献_第10页

Effects of four weeks intervention combining high-definition transcranial direct current stimulation and foot core exercise on dynamic postural stability 结合高清经颅直流电刺激和足部核心运动的四周干预对动态姿势稳定性的影响。

IF 2.4 3区医学

Journal of biomechanics Pub Date : 2024-11-07 DOI: 10.1016/j.jbiomech.2024.112418

Baofeng Wang , Bin Shen , Songlin Xiao , Junhong Zhou , Weijie Fu

{"title":"Effects of four weeks intervention combining high-definition transcranial direct current stimulation and foot core exercise on dynamic postural stability","authors":"Baofeng Wang , Bin Shen , Songlin Xiao , Junhong Zhou , Weijie Fu","doi":"10.1016/j.jbiomech.2024.112418","DOIUrl":"10.1016/j.jbiomech.2024.112418","url":null,"abstract":"<div><div>This study aimed to evaluate the effect of combining high-definition transcranial direct current stimulation (HD-tDCS) with foot core exercise (FCE) on dynamic postural stability and to determine whether the improvement achieved through this mix-type intervention outperforms the intervention of HD-tDCS and FCE alone. Sixty healthy males were recruited and randomly divided into four groups: (1) HD-tDCS + FCE group (HD-tDCS combined with FCE intervention); (2) s-tDCS + FCE (sham tDCS combined with FCE intervention); (3) HD-tDCS group which only received HD-tDCS; (4) FCE group which only performed FCE. All participants received a four-week intervention (3 times a week, 20 min each time). The Y-balance task was completed before and after the intervention. The maximum reaching distance was recorded, and the data of the center of pressure (COP) were collected by a three-dimensional force plate to calculate COP displacement and velocity. No significant change in COP displacement was found among the four groups. However, the COP velocity decreased significantly in the posteromedial direction after HD-tDCS + FCE intervention compared with the baseline. The maximum reach distance was significantly increased after HD-tDCS + FCE intervention in the posteromedial (<em>p</em> < 0.001) and posterolateral (<em>p</em> < 0.001) directions of the Y balance task compared with the baseline, and the extent of increase was greater than that in the three other groups. The intervention of HD-tDCS combined with FCE may exert a synergistic effect and more effectively improve dynamic postural stability.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"177 ","pages":"Article 112418"},"PeriodicalIF":2.4,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142621111","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

Influence of custom dynamic orthoses on tibiotalar joint reaction force and contact stress: A cadaveric study 定制动态矫形器对胫骨关节反作用力和接触应力的影响：尸体研究

IF 2.4 3区医学

Journal of biomechanics Pub Date : 2024-11-07 DOI: 10.1016/j.jbiomech.2024.112420

Lucinda Williamson , Marc Brouillette , Tristan Miller , Jessica Goetz , Jason Wilken , Donald D. Anderson

{"title":"Influence of custom dynamic orthoses on tibiotalar joint reaction force and contact stress: A cadaveric study","authors":"Lucinda Williamson , Marc Brouillette , Tristan Miller , Jessica Goetz , Jason Wilken , Donald D. Anderson","doi":"10.1016/j.jbiomech.2024.112420","DOIUrl":"10.1016/j.jbiomech.2024.112420","url":null,"abstract":"<div><div>Post-traumatic osteoarthritis (PTOA) often develops following tibial pilon fractures. Evidence suggesting PTOA development is driven by elevated articular contact stress from residual malreduction has led surgeons to strive for precise articular reduction, typically at the cost of extended operative time. Post-operative bracing using carbon fiber custom dynamic orthoses (CDOs) offers another means to decrease tibiotalar joint reaction force (JRF) and contact stress. The purpose of this cadaveric study was to measure how CDO stiffness influences ankle JRF and contact stress over the stance phase of gait.</div><div>A servohydraulic load frame was used to test five cadaver ankles, with axial loading (240–330 N) and pneumatic actuation of the Achilles tendon (50–436 N) serving to quasi-statically model multiple points in the stance phase of gait. Three CDO rotational stiffness conditions were tested: (1) No CDO–0 Nm/deg, (2) low stiffness CDO–1.8 Nm/deg, and (3) moderate stiffness CDO–2.3 Nm/deg. JRF and contact stresses were measured using a piezoresistive pressure sensor inserted into the tibiotalar joint. An insole plantar pressure sensor placed between the cadaveric foot and CDO footplate measured limb/device interactions via the plantar center of pressure (COP).</div><div>As limb loading progressed through stance, the plantar COP progressed from hindfoot to forefoot, as it would in normal gait. Both CDOs demonstrated decreases in JRF, reaching as high as 32% for the low CDO and 26% for the moderate CDO, with associated decreases in contact stress. This suggests that post-operative bracing could lessen PTOA risk after pilon fractures.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"177 ","pages":"Article 112420"},"PeriodicalIF":2.4,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142721473","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

Bilateral symmetry assessment of healthy forearm kinematics using 4D-CT 利用 4D-CT 评估健康前臂运动学的双侧对称性。

IF 2.4 3区医学

Journal of biomechanics Pub Date : 2024-11-06 DOI: 10.1016/j.jbiomech.2024.112417

Joris G.M. Oonk , Johannes G.G. Dobbe , Frederique T. van der Zeeuw , Loes Ettema , Gustav J. Strijkers , Geert J. Streekstra

{"title":"Bilateral symmetry assessment of healthy forearm kinematics using 4D-CT","authors":"Joris G.M. Oonk , Johannes G.G. Dobbe , Frederique T. van der Zeeuw , Loes Ettema , Gustav J. Strijkers , Geert J. Streekstra","doi":"10.1016/j.jbiomech.2024.112417","DOIUrl":"10.1016/j.jbiomech.2024.112417","url":null,"abstract":"<div><div>Advanced stage distal radio-ulnar joint (DRUJ) injury may warrant radius corrective osteotomy or arthroplasty. These procedures aim to restore geometry, function and kinematics and could benefit from preoperative planning where the contralateral forearm is typically used as reference. Natural variations regarding geometry and function between forearms are known but kinematic differences are not. This work aimed to quantify bilateral differences in forearm kinematics. Consequently, 4D-CT data of ten healthy volunteers was acquired, imaging motion of both forearm joints. Segmentation and registration of the radius and ulna bones resulted in a 3D representation of forearm rotation. Subsequently, the forearm rotation axis, radius translation along the ulna and radius rotation around its own inertial axis were calculated. The rotation axis of the right arm was mirrored to set up a comparison with the left arm. All other differences were calculated directly. The mean angle and distance between forearm rotation axes were 0.6° and 0.8 mm. The mean difference in radius translation along the ulna was 0.9 mm. On average, radius rotation around the radius’ inertial axis differed 2.6°, between forearms. This study’s findings can benefit DRUJ surgery preoperative planning and postoperative kinematic evaluation.</div><div>Level of evidence: IV.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"177 ","pages":"Article 112417"},"PeriodicalIF":2.4,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142621110","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

Passive-dynamic ankle-foot orthoses change post-stroke lower extremity constituent work profile 被动动态踝足矫形器改变了中风后下肢的工作状况。

IF 2.4 3区医学

Journal of biomechanics Pub Date : 2024-11-04 DOI: 10.1016/j.jbiomech.2024.112414

Jacob T. Skigen , Corey A. Koller , Darcy S. Reisman , Zahra N. McKee , Shay R. Pinhey , Jason M. Wilken , Elisa S. Arch

{"title":"Passive-dynamic ankle-foot orthoses change post-stroke lower extremity constituent work profile","authors":"Jacob T. Skigen , Corey A. Koller , Darcy S. Reisman , Zahra N. McKee , Shay R. Pinhey , Jason M. Wilken , Elisa S. Arch","doi":"10.1016/j.jbiomech.2024.112414","DOIUrl":"10.1016/j.jbiomech.2024.112414","url":null,"abstract":"<div><div>Stiffness-customized passive-dynamic ankle–foot orthoses (PD-AFOs) have been shown to reduce the mechanical cost of transport (COT) of individuals post-stroke. However, the mechanisms underlying this reduced COT are unknown. Therefore, this study aimed to identify the factors driving COT reduction with PD-AFO use for individuals post-stroke. Results showed that changes in limb work were strongly correlated to changes in COT with the PD-AFO compared to No AFO in the paretic (tau = 0.637, p < 0.001) and non-paretic (tau = 0.621, p < 0.001) limbs. There was also a strong correlation between changes in limb work and changes in COT compared to SOC AFO in the paretic (tau = 0.569, p < 0.001) and non-paretic (tau = 0.503, p = 0.003) limbs. Conversely, changes in stride length and changes in COT were not correlated. Changes in COT between No AFO and PD-AFO were moderately correlated to the number of constituents that performed less mechanical work for both the paretic (tau = −0.462, p = 0.009) and non-paretic (tau = −0.402, p = 0.025) limbs. Compared to walking with SOC AFOs, there was a moderate correlation between COT and the number of constituents in the paretic limb (tau = −0.458, p = 0.011) but not the non-paretic limb (tau = −0.247, p = 0.173). These findings indicate that PD-AFOs reduce COT primarily through small changes in work across many lower limb constituents. Understanding how COT reduction occurs can help optimize PD-AFO design and possibly other rehabilitation interventions for individuals post-stroke.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"177 ","pages":"Article 112414"},"PeriodicalIF":2.4,"publicationDate":"2024-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142604695","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

Biomechanical properties of various rat rotator cuff repair techniques 各种大鼠肩袖修复技术的生物力学特性。

IF 2.4 3区医学

Journal of biomechanics Pub Date : 2024-11-02 DOI: 10.1016/j.jbiomech.2024.112399

Mohamed Abozaid, Elameen Adam, Aida Sarcon, Kai-Nan An, Chunfeng Zhao

{"title":"Biomechanical properties of various rat rotator cuff repair techniques","authors":"Mohamed Abozaid, Elameen Adam, Aida Sarcon, Kai-Nan An, Chunfeng Zhao","doi":"10.1016/j.jbiomech.2024.112399","DOIUrl":"10.1016/j.jbiomech.2024.112399","url":null,"abstract":"<div><div>While rat models are frequently used to study tendon healing, there is a lack of research comparing various rotator cuff repair methods in this animal model. Determining the most effective method to begin with is pivotal for biological studies focused on healing augmentation. No study to date has shown the superiority of one repair over the other for rotator cuff repair in a rat model. We performed a biomechanic study using a rat model to study the strength of four common grasping techniques. We assessed if the bone tunnel trajectory influenced the early biomechanics of the repair at postoperative day 0 (POD0). Sixty cadaveric rat shoulders were divided equally into 6 groups; 4 groups were allocated for the biomechanical strength testing based on either a (1) modified Mason Allen (MM), (2) modified Kessler loop (MK), (3) horizontal mattress (HM), or a (4) simple interrupted stitch (SS) technique. The remaining 2 groups were used to evaluate two tunneling angles: a transverse tunnel (TT) that was perpendicular to the long humeral axis, or a longitudinal tunnel (LT) that was 30<sup>◦</sup> angle to the humerus. MM had the highest mean failure load, followed by MK, HM, and SS. Pairwise comparison revealed that MM was stronger than SS and HM (P = 0.025 and P = 0.026, respectively), although similar to the MK (P = 0.881). MM was stiffer than MK (P < 0.001), HM (P = 0.008), and SS (P < 0.001). The TT and LT had similar loads to failure and stiffness. Our study suggests that the MM technique provides a stronger and stiffer rotator cuff repair than the others.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"177 ","pages":"Article 112399"},"PeriodicalIF":2.4,"publicationDate":"2024-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142604688","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

Influence of multibody kinematic optimisation pipeline on marker residual errors 多体运动学优化管道对标记残余误差的影响。

IF 2.4 3区医学

Journal of biomechanics Pub Date : 2024-11-01 DOI: 10.1016/j.jbiomech.2024.112395

Vignesh Radhakrishnan, Samadhan Patil, Adar Pelah, Peter Ellison

{"title":"Influence of multibody kinematic optimisation pipeline on marker residual errors","authors":"Vignesh Radhakrishnan, Samadhan Patil, Adar Pelah, Peter Ellison","doi":"10.1016/j.jbiomech.2024.112395","DOIUrl":"10.1016/j.jbiomech.2024.112395","url":null,"abstract":"<div><div>Residual errors are used as a goodness-of-fit metric of the musculoskeletal model to the experimental data in multibody kinematic optimisation (MKO) analyses. Despite many studies reporting residual errors as a criterion for evaluating their proposed algorithm or model, the validity of residual errors as a performance metric has been questioned, with studies indicating a non-causal relationship between residual errors and computed joint angles. Additionally, the impact of different parameters of an MKO pipeline on residual errors has not been analysed. In our study, we have investigated the effect of each step of the MKO pipeline on residual errors, and the existence of a causal relationship between residual errors and joint angles. Increases in residual errors from the baseline model (13.84 [12.72, 15.15]mm) were obtained for: models with marker registration errors of 1.25 cm (16.36 [15.37, 17.57]mm); models with segment scaling errors of 1.25 cm (14.84 [13.77, 16.24]mm); variation in marker weighting scheme (15.28[14.00, 16.85]mm); and models with differing joint constraints (18.21[17.37, 19.11]mm). We also observed that significant variation in residual errors results in significant variation in computed joint angles, with increases in residual error positively correlated with increases in joint angle errors when the same MKO pipeline is employed. Our findings support the existence of a causal relationship and present the significant effect the MKO pipeline has on residual errors. We believe our results can further the discussion of residual errors as a goodness-of-fit metric, specifically in the absence of artefact-free bone movement.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"177 ","pages":"Article 112395"},"PeriodicalIF":2.4,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142604693","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

The Association Between Foot Morphology and Foot Loading During Gait 步态时足部形态与足部负荷之间的关系

IF 2.4 3区医学

Journal of biomechanics Pub Date : 2024-11-01 DOI: 10.1016/j.jbiomech.2024.112396

Kenzo M. Cotton , Xinyi Dan , Edward Godbold , Naomi Frankston , Milad Zarei , Yan Ma , MaCalus V. Hogan , William Anderst

{"title":"The Association Between Foot Morphology and Foot Loading During Gait","authors":"Kenzo M. Cotton , Xinyi Dan , Edward Godbold , Naomi Frankston , Milad Zarei , Yan Ma , MaCalus V. Hogan , William Anderst","doi":"10.1016/j.jbiomech.2024.112396","DOIUrl":"10.1016/j.jbiomech.2024.112396","url":null,"abstract":"<div><div>The perceived association between foot type and injury risk has inspired the development of many foot typing methods. The purpose of this study was to determine how well different foot typing methods explained variations in regional foot loading in asymptomatic adults during gait, while considering age, sex, and walking speed as covariates. Six methods were used to determine foot type in 92 asymptomatic adults. An insole pressure sensor system measured peak force and force-time integral during treadmill walking at a self-selected pace. The foot was divided into nine regions and the association between foot type and foot loading was analyzed using generalized estimating equations (GEE) while accounting for the covariates. Over an average of 250 steps per individual, the results demonstrated variability in the association between regional foot loading and foot type. Specifically, Arch Index and X-Ray Arch Type correlated with hindfoot and midfoot loading, while Foot Posture Index correlated with medial midfoot, forefoot, and toe loading. Calcaneal Pitch and Meary’s Angle correlated with medial hindfoot, midfoot, and forefoot loading, while Varus/valgus angle correlated with loading in the forefoot and toes. The location and direction of associations were generally similar for Calcaneal Pitch, Meary’s Angle, and X-Ray Arch Type, and opposite of Arch Index. The analyses demonstrated that walking speed, age, and sex were all important factors that affected the relationship between plantar loading and foot type. Specific foot type methods correlate better with loading in specific foot regions, potentially making them better to evaluate injury risk in those regions.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"177 ","pages":"Article 112396"},"PeriodicalIF":2.4,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142568585","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

Three-dimensional analysis of locomotion patterns after hindlimb suspension and subsequent long-term reloading in growing rats 对生长期大鼠后肢悬吊和随后长期重装后的运动模式进行三维分析。

IF 2.4 3区医学

Journal of biomechanics Pub Date : 2024-11-01 DOI: 10.1016/j.jbiomech.2024.112389

Norikazu Nishida , Marina Kanehara , Akinori Kaneguchi , Junya Ozawa

{"title":"Three-dimensional analysis of locomotion patterns after hindlimb suspension and subsequent long-term reloading in growing rats","authors":"Norikazu Nishida , Marina Kanehara , Akinori Kaneguchi , Junya Ozawa","doi":"10.1016/j.jbiomech.2024.112389","DOIUrl":"10.1016/j.jbiomech.2024.112389","url":null,"abstract":"<div><div>The long-term effects of insufficient weight loading during growth on locomotion patterns are not fully understood. The purpose of this study was to determine 1) the effects of hindlimb suspension (HS) in skeletally immature rats on locomotion patterns using a treadmill and a three-dimensional (3D) motion analysis system, and 2) the relationships between locomotion patterns and femoral morphologies, which were reconstructed from 3D computed tomography images taken at 54 weeks old. Four-week-old female rats were subjected to HS four or eight weeks, followed by reloading for until reaching up to 54 weeks old. Age-matched untreated rats served as controls. Motion analysis revealed that four and/or eight weeks of HS resulted in increased pelvis oscillation in the frontal plane during steps, decreased hip adduction angle, and toe-out (increased foot abduction angle) during the load response phase at one and five weeks after reloading. Interestingly, the decreased hip adduction angle and toe-out induced by eight weeks of HS persisted even at 54 weeks old. Pearson’s correlation analysis revealed a strong relationship between the hip adduction angle and femoral anteversion angle (r = -0.78) and a moderate relationship between the medial/lateral condyle height (an index of asymmetric condyle size) and toe-out angle (r = 0.66). These results suggest that insufficient weight loading during growth may induce abnormal locomotion patterns via abnormal femoral morphologies that may persist over time.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"176 ","pages":"Article 112389"},"PeriodicalIF":2.4,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142545694","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

Frequency and amplitude dependence of nuclear displacement and phase delay in mechanical vibrations for determining cellular natural frequency 用于确定蜂窝固有频率的机械振动中核位移和相位延迟的频率和振幅依赖性。

IF 2.4 3区医学

Journal of biomechanics Pub Date : 2024-11-01 DOI: 10.1016/j.jbiomech.2024.112403

Yuri Kuroki, Toshihiko Shiraishi

{"title":"Frequency and amplitude dependence of nuclear displacement and phase delay in mechanical vibrations for determining cellular natural frequency","authors":"Yuri Kuroki, Toshihiko Shiraishi","doi":"10.1016/j.jbiomech.2024.112403","DOIUrl":"10.1016/j.jbiomech.2024.112403","url":null,"abstract":"<div><div>Cultured cells biochemically respond to mechanical vibrations. However, the mechanisms of sensing mechanical vibrations and transducing biochemical responses remain unclear. A previous study reported that the expression of the alkaline phosphatase gene of osteoblastic cell under mechanical vibrations peaks at 50 Hz, which seems like a resonance curve in the mechanical vibration theory. Since forced displacement excitation is a dynamic mechanical stimulus that differs from other static mechanical stimuli in that an external force is equivalent to inertia, force is apparently exerted on the mass element by considering the equation of motion. In this study, the method for obtaining the change of a nucleus’s relative displacement to an excited dish was refined, and the frequency and acceleration amplitude dependence of the nucleus’s relative displacement and phase delay under mechanical vibrations was demonstrated by regarding a cell model as a vibration system. The change of the relative displacement of a HeLa nucleus to an excited dish decreases with increasing frequency in the 12.5–100 Hz range at 0.5 G and increases with increasing acceleration amplitude in the 0.5–2.0 G range at 50 Hz. Phase reversal occurs between 12.5 Hz and 50 Hz, which suggests the existence of the natural frequency of the cell between 12.5 Hz and 50 Hz. The single actin filament tension estimated from the nucleus’s relative displacement change was 2.3–10 pN and can be a biochemical response of the mechanotransducer. These findings can contribute to clarifying the mechanism of cell mechanotransduction in dynamic mechanical stimuli.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"177 ","pages":"Article 112403"},"PeriodicalIF":2.4,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142621114","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

Evaluation of mandibular motions in patients with anterior disc displacement during mouth opening and closing using finite helical axis 使用有限螺旋轴评估椎间盘前移位患者在张口和闭口时的下颌骨运动。

IF 2.4 3区医学

Journal of biomechanics Pub Date : 2024-11-01 DOI: 10.1016/j.jbiomech.2024.112393

Haidong Teng , Hedi Ma , Bingmei Shao , Zhan Liu

{"title":"Evaluation of mandibular motions in patients with anterior disc displacement during mouth opening and closing using finite helical axis","authors":"Haidong Teng , Hedi Ma , Bingmei Shao , Zhan Liu","doi":"10.1016/j.jbiomech.2024.112393","DOIUrl":"10.1016/j.jbiomech.2024.112393","url":null,"abstract":"<div><div>Understanding temporomandibular joint (TMJ) kinematics is essential for the clinical diagnosis and treatment of TMJ disorders. Yet, a comprehensive description of mandibular motion information in patients with anterior disc displacement (ADD) is lacking. The finite helical axis (FHA) is a mathematical model describing the motion of a rigid body in space. This model quantifies mandibular motion patterns by differentiating between rotation around the FHA and translation along it. This study aimed to compare the mandibular motion patterns between patients with ADD and asymptomatic subjects during mouth opening and closing utilizing the FHA. Ten asymptomatic subjects (2 females and 8 males, aged 19–22) and ten patients with ADD (8 females and 2 males, aged 19–57) were tracked using an optical motion tracking system for mouth opening and closing. The FHA during mouth opening and closing was determined from motion trajectory. The distance from the condylar center to the FHA (d<sub>CP</sub>), the angles between the FHA and the head coordinate system (θ<sub>x</sub>, θ<sub>y</sub>, θ<sub>z</sub>), and the global fluctuation of the FHA spatial orientation (θ<sub>f</sub>) were further calculated. In addition, the helical axis of each frame relative to the initial frame was computed to determine the maximum rotation angle (Θ<sub>max</sub>) and maximum offset (T<sub>max</sub>) of mandibular motion during mouth opening and closing. It was found that Θ<sub>max</sub>, T<sub>max</sub>, d<sub>LCPmean</sub>, d<sub>LCPmin</sub>, θ<sub>x</sub>, and θ<sub>f</sub> for patients with ADD differed significantly from those of asymptomatic subjects. These findings imply that the FHA effectively describes the disparities between patients with ADD and asymptomatic subjects.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"176 ","pages":"Article 112393"},"PeriodicalIF":2.4,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142545682","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