Journal of biomechanics最新文献

{"title":"A predictive method for estimating the glenohumeral joint center from palpable landmarks using multiple linear regression trained on CT data","authors":"António Sobral,&nbsp;João Folgado,&nbsp;Carlos Quental","doi":"10.1016/j.jbiomech.2025.112954","DOIUrl":"10.1016/j.jbiomech.2025.112954","url":null,"abstract":"<div><div>Human motion analysis often relies on skin markers to define local reference frames for tracking the movement of body segments. For the humerus, defining its local reference frame requires estimating the glenohumeral joint rotation center (GH-r), which is not directly palpable. Multiple linear regression models have been developed to estimate the GH-r from palpable landmarks, but they present limitations that affect their performance. The objective of this study was to develop a linear regression model that improves GH-r estimation from palpable landmarks and addresses key shortcomings of existing approaches. A dataset of 73 CT scans was divided into training, validation, and test sets using a 60:20:20 ratio. Several linear regression models were constructed using different algorithms, with 4 scapular skin landmarks digitized from the CT scans and subject characteristics as predictors, and the GH-r coordinates as dependent variables. The ground-truth GH-r was estimated through spherical fitting of the humeral head. The final regression model, selected for its favorable balance between accuracy and simplicity, achieved a mean Euclidean distance error (EDE) of 6.81 mm on the test set, representing a reduction of at least 10.73 mm compared to established predictive models of the GH-r applied to the same dataset, a difference that was statistically significant (p &lt; 0.001). Sensitivity analyses to marker placement variability showed an increase in mean EDE up to 8.46 mm, still well below the errors obtained for the other literature models. Overall, the model’s performance was not markedly affected by the observed inter-observer variability, further supporting its advantages.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"192 ","pages":"Article 112954"},"PeriodicalIF":2.4,"publicationDate":"2025-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145046568","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":"Knockout of collagen V in development, but not in skeletal maturity, leads to long-term deficits in supraspinatus tendon mechanics in mice","authors":"Jeremy D. Eekhoff,&nbsp;Mitchell J. Hallman,&nbsp;Michael S. DiStefano,&nbsp;Rebecca L. Betts,&nbsp;Courtney A. Nuss,&nbsp;Stephanie N. Weiss,&nbsp;Andrew F. Kuntz,&nbsp;Louis J. Soslowsky","doi":"10.1016/j.jbiomech.2025.112956","DOIUrl":"10.1016/j.jbiomech.2025.112956","url":null,"abstract":"<div><div>Collagen V is a key matrix protein involved in fibril nucleation and lateral fibril growth during extracellular matrix assembly. Genetic mouse models have been used to investigate the role of collagen V in tendon, which showed deficient mechanical properties and aberrant fibril structure in the absence of collagen V. However, the lasting effects of collagen V deficiency later into adulthood remain unknown, as well as the role of collagen V in maintaining a mature matrix. This study therefore investigated the long-term effects of collagen V reduction on tendon as well as its role in mature tendon matrix in adulthood. Tendon-targeted conditional <em>Col5a1</em> knockout, which excises <em>Col5a1</em> alleles early in development, had long-term impact on tendon structure and function in 300-day old mice. Gene expression was altered with differential expression of primarily matrix and matrix remodeling genes. Regional changes in cellular shape and density were consistent with typical behavior in tendinopathy. Fibril diameters were increased due to dysregulated lateral growth. Deficits in mechanical properties indicate a weaker tendon matrix after knockout, although deformation patterns of collagen fibrils were not affected. In contrast, inducing collagen V knockdown in a mature tendon matrix at 120-days old did not cause substantial changes in any of the above-mentioned properties in 300-day old mice. In conclusion, these findings highlight the important function of collagen V in matrix assembly that has lasting effects into later ages, even though collagen V has little role in homeostatic maintenance of a mature tendon matrix.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"192 ","pages":"Article 112956"},"PeriodicalIF":2.4,"publicationDate":"2025-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145046566","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":"A polygon model of the functional base-of-support during standing improves the accuracy of balance analysis","authors":"Matthew Millard ,&nbsp;Lizeth H. Sloot","doi":"10.1016/j.jbiomech.2025.112927","DOIUrl":"10.1016/j.jbiomech.2025.112927","url":null,"abstract":"<div><div>Mathematical balance models have the potential to identify people at risk of falling. However, most balance models depend on a model of the base-of-support (BOS) of the feet to calculate how well someone is balancing. Here, we evaluate the functional base-of-support (fBOS) during standing: the convex polygon on the bottom of the foot that can support a large fraction of the body’s weight. First, we develop a geometric model of the fBOS by measuring the center-of-pressure (COP) and kinematic data of the feet of 27 younger adults instructed to move their body in large loops without taking a step. Next, we extract a planar convex polygon that contains the COP data. Finally, we compare the area of this fBOS model to a marker-based BOS model before evaluating if the fBOS differs across four common conditions: footwear, stance-width, foot dominance, and during single and double-stance. We found that the fBOS is much smaller (23% the size) than a marker-based BOS model. Our analysis suggests that using the fBOS, rather than a marker-based BOS, can improve the accuracy of the margin-of-stability by 20% of foot width and 16% of the length. In addition, we found that the fBOS area does not differ across footwear (<span><math><mrow><mi>p</mi><mo>=</mo><mn>0</mn><mo>.</mo><mn>88</mn></mrow></math></span>), stance-width (<span><math><mrow><mi>p</mi><mo>=</mo><mn>0</mn><mo>.</mo><mn>88</mn></mrow></math></span>), and foot dominance (<span><math><mrow><mi>p</mi><mo>=</mo><mn>0</mn><mo>.</mo><mn>68</mn></mrow></math></span>), but during single stance, the fBOS is 17% (<span><math><mrow><mi>p</mi><mo>=</mo><mn>0</mn><mo>.</mo><mn>0003</mn></mrow></math></span>) larger than during double-stance. The variability of the fBOS area suggests that future studies should establish the repeatability and reliability of the assessment and systematically study the effects of different types of footwear. We have put the fBOS models, example data, and code in the public domain to help others build on our work.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"192 ","pages":"Article 112927"},"PeriodicalIF":2.4,"publicationDate":"2025-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145080851","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":"Clinical integration of markerless motion capture: A multicentre study of gait in knee osteoarthritis","authors":"Jereme Outerleys ,&nbsp;Elise Laende ,&nbsp;Monica Malek ,&nbsp;Stephanie Civiero ,&nbsp;Kim Madden ,&nbsp;Matthew Ruder ,&nbsp;Michael Dunbar ,&nbsp;Anthony Adili ,&nbsp;Dylan Kobsar ,&nbsp;Janie Wilson ,&nbsp;Kevin Deluzio","doi":"10.1016/j.jbiomech.2025.112952","DOIUrl":"10.1016/j.jbiomech.2025.112952","url":null,"abstract":"<div><div>Markerless motion capture addresses key barriers limiting the clinical uptake of biomechanical assessments by enabling efficient data collection and standardized modeling, making it well-suited for multicentre research. This study assessed whether gait deviations associated with knee osteoarthritis (OA) could be consistently detected using markerless motion capture across three clinical centres in Canada. Gait data from 486 participants (351 with knee OA; 135 controls) were analyzed, with body segment kinematics estimated from video using Theia3D. Principal component analysis and linear models were used to evaluate joint kinematics and temporal-distance parameters across groups and sites. After pooling data across centres, individuals with knee OA exhibited characteristic gait deviations, including slower walking speed, reduced hip, knee, and ankle range of motion, and increased knee adduction, compared to controls. These deviations were observed consistently across all three centres. Inter-site differences in joint kinematics were minor (RMS &lt; 3°), remained within reported inter-site error thresholds from marker-based systems, and did not obscure group-level effects. These findings demonstrate that clinically meaningful gait deviations can be reliably detected using markerless motion capture in varied clinical environments without extensive standardization. This work supports its use in multicentre studies and highlights its potential to enable large-scale biomechanical research, an essential step toward broader clinical integration of movement analysis.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"192 ","pages":"Article 112952"},"PeriodicalIF":2.4,"publicationDate":"2025-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145080821","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":"Regional changes in shear modulus of the biceps femoris long head following load application to the biceps femoris short head","authors":"Gakuto Nakao ,&nbsp;Ginji Nara ,&nbsp;Risa Adachi ,&nbsp;Koki Ishiyama ,&nbsp;Kazuyoshi Kozawa ,&nbsp;Keita Sekiguchi ,&nbsp;Kanna Nagaishi ,&nbsp;Kousuke Shiwaku ,&nbsp;Norio Hayashi ,&nbsp;Jurdan Mendiguchia ,&nbsp;Raki Kawama ,&nbsp;Nobuhiro Aoki ,&nbsp;Masaki Katayose ,&nbsp;Keigo Taniguchi","doi":"10.1016/j.jbiomech.2025.112947","DOIUrl":"10.1016/j.jbiomech.2025.112947","url":null,"abstract":"<div><div>Understanding the mechanical behavior of the biceps femoris long head (BFlh) may be insightful due to its high susceptibility to strain injuries, particularly during high-speed running in sports, such as soccer and track and field. While prior research has focused on intrinsic muscle properties, emerging evidence suggests that the biceps femoris short head (BFsh) may influence BFlh tension. Thus, we examined the effects of BFsh load application on the tensile strength and regional shear modulus of the BFlh. Seven legs from four cadaveric specimens (mean age: 83.2 ± 7.4 years) embalmed using the Thiel method were used. BFlh was secured to a mechanical testing device equipped with a load cell, whereas BFsh was connected to a custom-built mechanical apparatus. A tensile strain of 8 % was applied to the BFlh, whereas incremental loads (0, 150, 300, 450, 600, and 750 g) were gradually added to the BFsh. The tensile force and shear modulus in the three BFlh regions (proximal, central, and distal) were recorded using shear wave elastography. The results demonstrated that BFsh loading notably reduced BFlh tensile strength, with the lowest tension at 750 g (<em>P</em> &lt; 0.01). The shear modulus decreased in the proximal and distal regions at loads &gt; 450 g (<em>P</em> &lt; 0.01), with no change in the central region. The distal region exhibited a greater decrease in shear modulus compared with the proximal and central regions (<em>P</em> &lt; 0.01). These findings suggest that BFsh loading reduces BFlh tensile strength and alters its mechanical properties, particularly in the distal region.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"192 ","pages":"Article 112947"},"PeriodicalIF":2.4,"publicationDate":"2025-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145020452","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 relationship between triceps surae muscle–tendon morphology and shear modulus across passive ankle range of motion in cerebral palsy","authors":"Francesco Cenni ,&nbsp;Maria Sukanen ,&nbsp;Alejandro Hernández-Belmonte ,&nbsp;Iida Laatikainen-Raussi ,&nbsp;Ines Vandekerckhove ,&nbsp;Taija Finni","doi":"10.1016/j.jbiomech.2025.112946","DOIUrl":"10.1016/j.jbiomech.2025.112946","url":null,"abstract":"<div><div>Alterations in skeletal muscle morphology and composition are critical factors in cerebral palsy (CP), including changes in passive stiffness and in belly and fascicle lengths. In this study, we quantified the relative contributions of muscle and tendon to passive stiffness across the ankle range of motion in individuals with CP and typically developing (TD) peers. We also investigated morphological factors underlying increased muscle stiffness. Twelve individuals with CP and 12 age-matched TD peers were recruited. 3D freehand ultrasonography was used to image the medial and lateral gastrocnemius, soleus, and Achilles tendon at three angles across the passive range of motion. From these datasets, muscle belly and fascicle lengths were estimated. Shear wave elastography assessed tissue passive stiffness. The shear modulus at the neutral ankle angle was significantly (p &lt; 0.0038) higher in CP (26.8 kPa for the medial and 20.2 kPa for lateral gastrocnemius) than in TD (19.7 and 14.1 kPa, respectively). When relating shear modulus to muscle belly strain, a significantly steeper slope in CP (3.31 kPa) than in TD (1.00 kPa) (p = 0.001) was found. In the CP group, the slope of muscle belly strain differed significantly from that of fascicle strain, whereas no such difference was observed in the TD group. Our results confirm an increase in passive muscle stiffness in individuals with CP, which remains consistent across the joint range. This elevated stiffness seems primarily associated with whole muscle belly strain, suggesting that changes in the extracellular matrix, rather than fascicle elasticity, may be the main contributor.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"192 ","pages":"Article 112946"},"PeriodicalIF":2.4,"publicationDate":"2025-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145007791","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":"Cardan sequence selection influences subtalar and talonavicular joint kinematics","authors":"Anthony H. Le ,&nbsp;Kassidy Knutson ,&nbsp;Andrew C. Peterson ,&nbsp;Bruce A. MacWilliams ,&nbsp;Karen M. Kruger ,&nbsp;Amy L. Lenz","doi":"10.1016/j.jbiomech.2025.112948","DOIUrl":"10.1016/j.jbiomech.2025.112948","url":null,"abstract":"<div><div>Cardan angle sequences are widely used to describe three-dimensional joint rotations in the foot and ankle, but differences in rotation order can complicate interpretation, especially in joints with multiplanar motion. This study systematically evaluated the influence of Cardan sequence selection on the kinematics of the tibiotalar, talofibular, tibiofibular, subtalar, and talonavicular joints using both <em>in vivo</em> biplane fluoroscopy gait analysis and <em>in vitro</em> passive joint kinematic data from robotic cadaveric simulation. Six Cardan sequences were evaluated to quantify their effects on joint angle profiles and range of motion. Tibiotalar, talofibular, and tibiofibular joint kinematics were largely consistent across Cardan sequences, supporting continued use of the ISB-recommended XYZ sequence (dorsiflexion/plantarflexion followed by inversion/eversion followed by internal/external rotation). Subtalar and talonavicular joint kinematics exhibited substantial sequence-dependent variations in reported joint angles during gait, prescribed tibial external/internal rotation, and prescribed tibial varus/valgus alignment motions. Sequences prioritizing the Y-axis (inversion/eversion) or Z-axis (internal/external rotation) produced the most significant differences relative to the XYZ sequence. Based on joint- and motion-specific sensitivity, we recommend the XYZ sequence for the tibiotalar, talofibular, and tibiofibular joints; YZX, ZXY, or ZYX sequences for prioritizing transverse subtalar joint motion and XYZ or XZY sequences for coronal subtalar joint motion; and XYZ, XZY, or YXZ sequences for sagittal and transverse talonavicular joint motion, with YZX sequence for coronal talonavicular joint motion. These findings highlight the importance of joint-specific rotation sequence selection to improve consistency, reduce crosstalk, and enhance the clinical relevance of foot and ankle kinematic analyses.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"192 ","pages":"Article 112948"},"PeriodicalIF":2.4,"publicationDate":"2025-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145086026","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":"Curvilinear sprint acceleration-speed profile in youth soccer players is constrained by tighter radii and sprinting side dominance","authors":"Ažbe Ribič ,&nbsp;Darjan Smajla ,&nbsp;Oskar Cvjetičanin ,&nbsp;Matic Sašek","doi":"10.1016/j.jbiomech.2025.112938","DOIUrl":"10.1016/j.jbiomech.2025.112938","url":null,"abstract":"<div><div>This study investigated how the acceleration-speed profile (ASP) of the weaker and stronger side changes at different radii. Twenty male youth soccer players completed 30 m linear and curvilinear sprints (12.15, 11.15, 9.15, 7.15, and 6.15 m radius) in three training sessions. Sprint speed and acceleration over time and distance were recorded using a GNSS device. The maximum theoretical speed (S₀), the acceleration (A₀), slope of the ASP (AS_slope), the area under the AS_slope (ASP_area), the acceleration at a sprint speed of 3 m/s (A₃), and the curvilinear sprint deficit (ASP_deficit) of the individual sprints were analyzed. The effects of side, radius, and their interaction were evaluated with 2 × 5 ANOVA and the post hoc tests. A significant effect of radius and side was observed for all variables (F ≥ 3.50, p ≤ 0.037, η² ≥ 0.15). The ASP_area and S₀ decreased at tighter radii. The A₃ and A₀ remained relatively unchanged, resulting in a steeper AS_slope, and a larger ASP_deficit. At the same radius, the weaker side CS had a smaller ASP_area, S₀, A₃, and a larger ASP_deficit. The ASP of the curvilinear sprint in youth soccer players is side-dependent at both ends (acceleration and top speed), while radii mainly affect late acceleration and top speed performance. These observations should be considered when adapting soccer players’ sprint training and monitoring external load based on acceleration.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"192 ","pages":"Article 112938"},"PeriodicalIF":2.4,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145020533","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":"Centerline-based quantification of true Lumen helical Morphology in Type B aortic dissection: Unlocking the potential of helicity as a geometric biomarker","authors":"Fikunwa O. Kolawole ,&nbsp;Johan Bondesson ,&nbsp;Brant W. Ullery ,&nbsp;Christopher P. Cheng","doi":"10.1016/j.jbiomech.2025.112933","DOIUrl":"10.1016/j.jbiomech.2025.112933","url":null,"abstract":"<div><div>The helical morphology of Type B aortic dissections (TBAD) represents a potentially important geometric biomarker that may influence dissection progression. While three-dimensional surface-based quantification methods provide accurate TBAD helicity assessment, their clinical adoption remains limited by significant processing time. We developed and validated a clinically practical centerline-based helicity quantification method using routine imaging software (TeraRecon) against an extensively validated surface-based method (SimVascular). In 87 TBAD patients, we semi-automatically extracted aortic, true lumen, and branch vessel centerlines from CT imaging. Helical parameters, including true lumen helical angle and peak helical twist, were computed relative to a standardized anatomical reference, enabling classification of patients into four distinct helicity categories: left-chiral, right-chiral, non-helical, and mixed-chiral patterns. The centerline method demonstrated 92% classification accuracy with excellent agreement with surface-based measurements (Cohen’s <span><math><mrow><mi>κ</mi><mo>=</mo><mn>0</mn><mo>.</mo><mn>88</mn></mrow></math></span>, <span><math><mrow><mi>p</mi><mo>&lt;</mo><mn>0</mn><mo>.</mo><mn>001</mn></mrow></math></span>). Wilcoxon signed-rank tests revealed a median difference of <span><math><mrow><mo>−</mo><mn>0</mn><mo>.</mo><msup><mrow><mn>4</mn></mrow><mrow><mo>∘</mo></mrow></msup></mrow></math></span> (<span><math><mrow><mi>z</mi><mo>=</mo><mo>−</mo><mn>1</mn><mo>.</mo><mn>08</mn></mrow></math></span>, <span><math><mrow><mi>p</mi><mo>=</mo><mn>0</mn><mo>.</mo><mn>28</mn></mrow></math></span>), indicating no statistically significant systematic bias between methods. This centerline approach we have developed provides clinically feasible TBAD helicity classification while maintaining excellent agreement with the gold-standard surface-based method. This technique can integrate seamlessly with existing clinical workflows, enabling practical assessment of TBAD helical morphology for enhanced risk stratification and personalized treatment planning.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"192 ","pages":"Article 112933"},"PeriodicalIF":2.4,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145020451","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":"Effect of forefoot strike and toe-out running on hip contact forces: A musculoskeletal modelling-based study","authors":"P.L. Leung ,&nbsp;R.S.S. Subasinghe Arachchige ,&nbsp;T.S. Ip ,&nbsp;C.H. Chan ,&nbsp;H.Y. Cheng ,&nbsp;P.Y. Hui ,&nbsp;H.L. Liu ,&nbsp;E.Y.L. Ho ,&nbsp;R.L.C. Kwan ,&nbsp;M. Sreenivasa ,&nbsp;R.T.H. Cheung","doi":"10.1016/j.jbiomech.2025.112936","DOIUrl":"10.1016/j.jbiomech.2025.112936","url":null,"abstract":"<div><div>Hip osteoarthritis (OA) is an increasingly significant public health concern, contributing to substantial economic and societal burden worldwide. Emerging evidence suggests that running may promote cartilage health through optimal joint loading. However, it remains unclear how modifications to running posture, such as altering footstrike patterns or adjusting foot progression angles, affect hip contact forces (HCF). This study investigated HCF differences across three running conditions: natural running, forefoot strike (FFS) modification, and toe-out modification. FFS may enhance shock attenuation through increased lower limb flexion and altered ankle mechanics, while toe-out running laterally shifts the center of pressure, reducing the lever arm. Ten healthy participants ran along a 20-meter walkway under the three running conditions in a randomized order. Running biomechanics were recorded using an 8-camera motion capture system synchronized with four force plates. Kinematic and kinetic data were used to calculate right-limb HCF during early and late stance using a musculoskeletal model and the software OpenSim. Within-subject differences in HCF across the three running conditions were analyzed with one-way repeated measures ANOVA. FFS running resulted in a significantly lower vertical HCF during early stance and a significantly higher vertical HCF during late stance compared to both natural running (early stance: <em>p</em> = 0.011; late stance: <em>p</em> = 0.004) and toe-out running (early stance: <em>p =</em> 0.028; late stance: <em>p =</em> 0.013). No statistically significant differences were observed in medial–lateral HCF during either early stance or late stance (<em>p</em> &gt; 0.220) across the three conditions. No significant differences in vertical or medial–lateral HCF were found between toe-out and natural running during either early or late stance (<em>p</em> &gt; 0.366). Footstrike modification appears to be a viable strategy to alter vertical HCF compared to natural and toe-out running. However, none of the selected strategies effectively modified HCF in the frontal plane. These findings have implications for developing targeted interventions to manage hip OA.</div></div>","PeriodicalId":15168,"journal":{"name":"Journal of biomechanics","volume":"192 ","pages":"Article 112936"},"PeriodicalIF":2.4,"publicationDate":"2025-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144989837","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}