Journal of biomechanics最新文献

{"title":"Comparison of kinematics between markerless and marker-based motion capture systems for change of direction maneuvers","authors":"Naoto Nishikawa ,&nbsp;Shun Watanabe ,&nbsp;Keizo Yamamoto","doi":"10.1016/j.jbiomech.2025.112965","DOIUrl":"10.1016/j.jbiomech.2025.112965","url":null,"abstract":"<div><div>Marker-based motion capture, a widely used method for three-dimensional motion analysis, entails important shortcomings, including soft tissue artifacts and constraints on experiment environments. By contrast, markerless systems require no reflective markers, show minimal inter-session variation, and remain unaffected by clothing, making them promising tools for athletic performance evaluation. This study was conducted to compare kinematic data obtained using the respective systems during change of direction (COD) maneuvers and to evaluate the applicability of markerless systems. Five trials of 90° COD maneuvers were performed by 23 male participants. Kinematic data were captured simultaneously using marker-based (Motion Analysis) and markerless systems (Theia Markerless Inc.). The markerless system used synchronized multi-camera deep learning to detect anatomical landmarks and to reconstruct full-body skeletal motion through triangulation and inverse kinematics. Trunk and lower-limb joint angles were calculated for both systems. Bland–Altman analysis, the intraclass correlation coefficient (ICC), root mean square deviation (RMSD), and normalized root mean square error (NRMSE) were used to compare the two systems. Both systems demonstrated good agreement for most joint angles. However, notable mean differences were found in ankle dorsiflexion (−10.92° [−18.38, −3.46]), knee flexion (−8.32° [−14.48, −2.13]), and hip external rotation (12.1° [−2.12, 26.33]). Most angles also showed good ICC values (&gt;0.75), indicating measurement reliability between the systems. These findings suggest that markerless systems can capture kinematic patterns reliably during COD maneuvers. However, comparing the magnitudes of joint angles with those of marker-based systems demands caution. This method is valid for COD analysis if system-specific differences are considered.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"192 ","pages":"Article 112965"},"PeriodicalIF":2.4,"publicationDate":"2025-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145102694","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}

{"title":"In vitro kinematic analysis of a new patient-matched polycarbonate urethane radiocarpal interposition arthroplasty","authors":"Jane Gruisen ,&nbsp;Philip Schormans ,&nbsp;Alex Roth ,&nbsp;Ilona Punt ,&nbsp;Aylvin Dias ,&nbsp;Geert Streekstra ,&nbsp;Iwan Dobbe ,&nbsp;Martijn Poeze ,&nbsp;Pascal Hannemann","doi":"10.1016/j.jbiomech.2025.112960","DOIUrl":"10.1016/j.jbiomech.2025.112960","url":null,"abstract":"<div><div>Current salvage procedures for patients with post-traumatic wrist osteoarthritis include excision of bone or tissue and/or fusion of wrist bones, making all surgical salvage procedures irreversible. Some of these salvage procedures decrease wrist mobility. A novel patient-matched polyurethane carbonate (PCU) radiocarpal interposition arthroplasty has recently been proposed as a reversible, motion-preserving solution. This experimental study evaluates the effect of the PCU radiocarpal implant on wrist range of motion (ROM) and carpal kinematics. Additionally, implant displacement is assessed during functional ROM.</div><div>The passive wrist ROM of three cadaveric arms was measured in a wrist motion simulator before and after implantation of the PCU radiocarpal implant by applying a 1 Nm Torque. Three-dimensional fluoroscopy scans of the wrist were acquired in 15° steps during flexion–extension (F/E = 60°/60°) to assess carpal bone and implant kinematics. The mean differences in carpal kinematics between native and implantation conditions were calculated per cadaveric wrist and averaged across all three specimens.</div><div>The mean wrist ROM did not demonstrate clinically relevant differences between the native and implantation conditions, except for a reduction of 10.3° in extension. Variations in carpal rotations and translations over the F/E curve were smaller than 2.5° and 2.2 mm and were therefore considered negligible. The PCU radiocarpal implants’ rotations and translations were maximally 6.3° and 1.1 mm during F/E.</div><div>Given these results, the PCU radiocarpal interposition arthroplasty may be a promising option for patients with post-traumatic radiocarpal arthritis, offering a balance between maintaining mobility and providing pain relief through a minimally invasive and reversible procedure.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"192 ","pages":"Article 112960"},"PeriodicalIF":2.4,"publicationDate":"2025-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145155485","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}

{"title":"Harnessing resistance: the impact of a passive exosuit on golf swing biomechanics","authors":"Alireza Nasirzadeh ,&nbsp;Song Min Lee ,&nbsp;Jihye Jang ,&nbsp;Jaewook Ryu ,&nbsp;Jeongho Choo ,&nbsp;Nakwon Ko ,&nbsp;Jin Hee Kim ,&nbsp;Yong Ung Kwon ,&nbsp;Giuk Lee","doi":"10.1016/j.jbiomech.2025.112958","DOIUrl":"10.1016/j.jbiomech.2025.112958","url":null,"abstract":"<div><div>Wearable passive resistance devices have emerged as potential tools for enhancing athletic performance without disrupting natural biomechanics. This study investigated the acute biomechanical impact of a novel passive exosuit designed to assist torso rotation and enhance clubhead speed (CHS). Twelve skilled golfers performed swings under two conditions: normal and exosuit-assisted. Compared to the normal condition, CHS significantly increased by 2.55 % (P = 0.009) when wearing the exosuit, rising from 43.3 ± 3.8  m/s to 44.4 ± 4.0  m/s. Although no significant differences were observed in X-factor at the top of the backswing, maximum X-factor, X-factor stretch, or maximum rate of X-factor stretch (MROS), the maximum rate of X-factor recoil (MROR) was significantly higher with the exosuit (P = 0.03), indicating enhanced rotational recoil during the downswing. Mechanical work analysis revealed a significantly greater total negative work during the backswing (P = 0.04) and a higher total positive work during the downswing (P = 0.03) in the transverse plane during swings with the exosuit, reflecting enhanced energy storage and return. These findings suggest that the current passive exosuit improves golf swing performance by augmenting rotational dynamics in the transverse plane without altering swing kinematics. This offers practical applications for performance training and biomechanical optimization in golf.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"192 ","pages":"Article 112958"},"PeriodicalIF":2.4,"publicationDate":"2025-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145091579","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}

{"title":"Assessment of blast lung injury risk using an advanced surrogate System: Evaluating chest protection efficacy in blast exposure scenarios","authors":"Johanna Boutillier ,&nbsp;Sébastien De Mezzo ,&nbsp;Nicolas Prat ,&nbsp;Pascal Magnan ,&nbsp;Pierre Naz","doi":"10.1016/j.jbiomech.2025.112963","DOIUrl":"10.1016/j.jbiomech.2025.112963","url":null,"abstract":"<div><div>When designing protective equipment for soldiers and law enforcement, blast threats are often overlooked, with the focus primarily on ballistic, stab, and fragment protection. However, primary blast injuries, which affect air-filled organs like the lungs and gastrointestinal tract, can be exacerbated by certain thoracic protective equipment. Using an anthropomorphic mannequin, BOPMAN (Blast OverPressure MANnequin), the effectiveness of a soft ballistic vest against blast threats of varying intensities was evaluated. The study involved detonations ranging from 85 g to 4 kg of C-4, with blast wave impulses from 17 kPa·ms to 237 kPa·ms. Both unprotected and protected conditions were tested, revealing a constant amplification factor of 1.36 ± 0.24 on metrics when the mannequin was equipped with a soft ballistic vest (SBV). Scenarios that were deemed safe without protection became hazardous when the vest was used. Estimated lung–injury risk has increased, ranging from 0.1 % to 29.3 %, suggesting pulmonary contusion and accompanying edema. High-speed videos showed the vest protection “slapping” the mannequin’s chest upon shock wave impact, likely due to an air gap between the vest and chest, which may explain the amplification of blast effects.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"192 ","pages":"Article 112963"},"PeriodicalIF":2.4,"publicationDate":"2025-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145086006","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}

{"title":"The impact of endomysium integrity on skeletal muscle fiber bundle mechanics","authors":"Paolo Carlo Danesini ,&nbsp;André Tomalka ,&nbsp;Tobias Siebert ,&nbsp;Filiz Ates","doi":"10.1016/j.jbiomech.2025.112957","DOIUrl":"10.1016/j.jbiomech.2025.112957","url":null,"abstract":"<div><div>The endomysium, the innermost layer of the extracellular matrix (ECM), was shown to play an important role in both passive and active force transmission. However, its mechanical contribution within muscle fiber bundles remains incompletely understood. We hypothesized that dissecting one of the endomysial connections within a fiber bundle would alter force production and lead to changes in sarcomere lengths and their heterogeneity. Muscle fiber bundles (n = 12) were extracted from the extensor digitorum longus muscles of rats and chemically skinned. Their passive and active stress-length relationships were measured under two conditions: (i) with intact endomysium and (ii) after blunt dissection of endomysial connections between two adjacent peripheral fibers. Disruption of endomysial continuity significantly reduced passive stress by 26.5 % <em>(p</em> &lt; 0.01) and active stress by 21.9 % <em>(p</em> &lt; 0.001) on average across all lengths tested. It also shifted the optimal fiber length (L_opt) to longer values by 6.2 % (<em>p &lt;</em> 0.01). Despite these mechanical changes, average sarcomere lengths (along fibers) and their heterogeneity remained unchanged. Length heterogeneity was only observed at a longer fiber length (1.3 L_opt) in the passive state before dissection. These findings demonstrate that endomysial connections are integral to the mechanical behavior of muscle fiber bundles, influencing both passive and active stress. The absence of sarcomere length changes along fibers suggests that other microstructural mechanisms, such as altered lattice spacing or impaired lateral force transmission, may underlie the observed changes. These results highlight the importance of ECM integrity in muscle mechanics and have implications for orthopedic interventions and neuromuscular disorder management.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"192 ","pages":"Article 112957"},"PeriodicalIF":2.4,"publicationDate":"2025-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145106317","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}

{"title":"Anticipatory postural adjustment for compensating forces and moments associated with isometric force production in an upper limb","authors":"Takumi Akamatsu,&nbsp;Masahiro Shinya","doi":"10.1016/j.jbiomech.2025.112961","DOIUrl":"10.1016/j.jbiomech.2025.112961","url":null,"abstract":"<div><div>Anticipatory postural adjustments (APAs) play a critical role in maintaining postural stability during voluntary movements, compensating proactively for expected perturbations. While previous studies have extensively documented APAs for linear perturbations associated with upper-limb movements, less is known about the anticipatory adjustments involved in counteracting rotational perturbations generated by unilateral force production. The present study aimed to elucidate how APAs are achieved through modulation of ground reaction forces (GRFs) under each foot, in preparation for horizontal-plane rotational perturbations induced by isometric unilateral handle-pulling tasks. Fifteen healthy participants performed rapid, isometric handle-pulling tasks in different horizontal directions (left, forward, and right) using either hand while standing on two force plates. Our results demonstrated that functional and direction-specific adjustments of bilateral GRFs were observed 50 ms before the onset of hand force. Specifically, anticipatory modulations in anterior-posterior GRFs under the left and right feet created condition-specific horizontal moments, effectively compensating for predicted rotational perturbations. Furthermore, statistical parametric mapping (SPM1D) analysis revealed that condition-specific GRF moments preceded hand-generated moments, reinforcing the feedforward nature of these adjustments. These findings highlight the importance of coordinated bilateral GRF control as a key mechanism for anticipatory postural stabilization.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"192 ","pages":"Article 112961"},"PeriodicalIF":2.4,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145102690","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}

{"title":"The effect of the collagen crosslinker genipin on early healing in a rat model of Achilles tendinopathy","authors":"Subhajit Konar ,&nbsp;Scott M Bolam ,&nbsp;Sophia Leung ,&nbsp;Mark H Vickers ,&nbsp;Jillian Cornish ,&nbsp;Dorit Naot ,&nbsp;David S Musson","doi":"10.1016/j.jbiomech.2025.112962","DOIUrl":"10.1016/j.jbiomech.2025.112962","url":null,"abstract":"<div><div>Achilles tendinopathy is characterized by deterioration of tissue integrity and biomechanical properties. Reduced tendon stiffness is detrimental to its function. Previous studies found that increased body mass is a risk factor for Achilles tendinopathy. We aimed to determine whether increasing the stiffness of damaged Achilles tendon by the collagen crosslinker genipin can improve early healing outcomes in an animal model of collagenase-induced tendinopathy, and whether the effect depends on body mass.</div><div>Male and female Sprague-Dawley rats were allocated to normal diet (ND) or high-fat diet (HFD) at weaning. At 17 weeks, each sex and diet group was divided into three treatment groups (n = 15): collagenase (CT), collagenase-genipin (CT-GT), and genipin (GT). Collagenase and genipin were injected into the Achilles tendons; contralateral tendons served as controls. After 10 days, Achilles tendons were collected for biomechanical and histological evaluation.</div><div>At the time of tendinopathy induction, animals fed HFD weighed on average, 14.5 % more than animals on ND. Biomechanical and histological changes characteristic of tendinopathy were observed in Achilles tendons of all animals treated with collagenase. Genipin had no effect on tendon biomechanical and histological properties: we found no differences between the GT and the control group, or between the CT-GT and the CT group.</div><div>In conclusion, 1 mM genipin did not improve the biomechanical properties of tendinopathic Achilles, and had no effect on early tendon healing in this rat model of collagenase-induced Achilles tendinopathy, irrespective of animal sex and weight. This is an important pre-clinical finding and can be used to direct future research, and prevent possible research wastage. One potential future direction is exploring innovative delivery systems to maintain higher local concentrations of genipin, that may be required to realize the potential of this molecule in tendon healing.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"192 ","pages":"Article 112962"},"PeriodicalIF":2.4,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145075047","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}

{"title":"Impact of ABLE 7-axes exoskeleton on upper limb kinematics during movements","authors":"Julia Peladeau ,&nbsp;Philippe Garrec ,&nbsp;Sébastien Laporte ,&nbsp;Xavier Bonnet","doi":"10.1016/j.jbiomech.2025.112953","DOIUrl":"10.1016/j.jbiomech.2025.112953","url":null,"abstract":"<div><div>The integration of exoskeletons in rehabilitation therapy requires understanding their impact on natural upper limb motion. This study therefore aimed to quantify the kinematic changes induced by the ABLE 7-axes exoskeleton. We hypothesize significant reductions in range of motion (ROM), movement velocity, and smoothness. To verify these hypotheses, fifteen healthy subjects were asked to perform a set of single-joint and multi-joint movements under three conditions: without exoskeleton (WE), with exoskeleton in human active mode (HA), and with exoskeleton in human passive mode (HP). Movements were captured using optoelectronic motion capture, analyzing their patterns, ROM, velocity, and smoothness. Results showed reductions of ROM between 10% and 76% across joints when using the exoskeleton, with shoulder internal/external rotation most affected (76% reduction) and a decrease of velocities by 29–80% in HA mode compared to unassisted movements. Multi-joint movements were less impacted than single-joint movements, while increased movement jerkiness was observed across all movements with the exoskeleton. These findings demonstrate that the ABLE 7-axes exoskeleton significantly impacts upper limb kinematics, particularly affecting shoulder motion, with implications for rehabilitation protocol design and exoskeleton development.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"192 ","pages":"Article 112953"},"PeriodicalIF":2.4,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145086011","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}

{"title":"Gait data generation using lightweight generative deep learning framework","authors":"Mainak Ghosh ,&nbsp;Anup Nandy ,&nbsp;Bidyut Kr. Patra ,&nbsp;R. Anitha ,&nbsp;Mohanavelu K.","doi":"10.1016/j.jbiomech.2025.112951","DOIUrl":"10.1016/j.jbiomech.2025.112951","url":null,"abstract":"<div><div>Human gait analysis is an intriguing area of research that supports sports science, robotic exoskeleton design, and clinical applications. However, the collection of gait data is a challenging task under physiological and ethical conditions, which leads to data scarcity. Many clinical works have utilized gait data generation using deep learning frameworks like Generative Adversarial Network (GAN) to address these limitations. However, most of these models are computationally intensive, which makes them impractical for real-world scenarios. To address these challenges, we propose a novel lightweight hybrid model ensembling a Feed-forward Neural Network with an Autoencoder, termed as FNN-AE model. The proposed architecture is designed to balance between model complexity and data fidelity. The FNN generates the gait data, while the AE refines it to resemble the real gait patterns closely. This model achieves satisfactory performance with state-of-the-art models while utilizing fewer parameters to reduce complexity. The proposed model is verified with the Newtonian equation of motion. The model generated data are tested on the OpenSim simulation platform to check the biomechanical feasibility of generated gait patterns.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"192 ","pages":"Article 112951"},"PeriodicalIF":2.4,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145060866","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}

{"title":"Establishing reference values for shoulder mobility and abduction strength in healthy adults","authors":"Daniel Garríguez-Pérez ,&nbsp;Yaiza Lopiz ,&nbsp;Lucía Domínguez-Jiménez ,&nbsp;Carlos García-Fernández ,&nbsp;Fernando Marco","doi":"10.1016/j.jbiomech.2025.112959","DOIUrl":"10.1016/j.jbiomech.2025.112959","url":null,"abstract":"<div><div>This study aims to establish normative values for shoulder ROM and abduction strength across different age and sex groups in healthy individuals. Both shoulders of 505 participants over 18 years of age, with no current or prior shoulder conditions, were evaluated. Measurements included ROM (flexion, abduction, external rotation, and internal rotation) and abduction strength. Participants were grouped by age (18–30, 31–45, 46–60, 61–75, over 75) and sex (male or female). A statistically significant inverse correlation was found between shoulder ROM and age (r = −0.45, p &lt; 0.001), indicating a decline in all shoulder movements with age (abduction: r = −0.3738; flexion: r = −0.3866; external rotation: r = −0.4012; internal rotation: r = −0.3729; all p &lt; 0.001). No significant differences in ROM were observed between sexes. Shoulder strength also decreased with age (r = −0.40, p &lt; 0.001) and was significantly higher in men than in women (10.6 ± 3.8 kg vs. 6.0 ± 2.0 kg, p &lt; 0.001). In conclusion, shoulder function declines physiologically with increasing age, mainly because of a decrease in internal rotation mobility and abduction strength. Also, there are clear sex-related differences in abduction strength of the shoulder which should be take into account when assessing shoulder function.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"192 ","pages":"Article 112959"},"PeriodicalIF":2.4,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145046567","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}