Clinical Biomechanics最新文献

{"title":"Effects of restraining forces on propulsion and other gait characteristics during treadmill walking post-stroke","authors":"S. Minkes-Weiland ,&nbsp;H. Houdijk ,&nbsp;S. Floor ,&nbsp;P.P. Hartman ,&nbsp;H.A. Reinders-Messelink ,&nbsp;L.H.V. van der Woude ,&nbsp;A.R. den Otter","doi":"10.1016/j.clinbiomech.2025.106664","DOIUrl":"10.1016/j.clinbiomech.2025.106664","url":null,"abstract":"<div><h3>Background</h3><div>A decreased propulsive capacity post stroke is associated with a diminished walking ability. When walking with a restraining force applied to the pelvis, more propulsion is required to enable forward progression. This may stimulate propulsion capacity in people post-stroke. Before incorporating restraining forces into training, their effects on propulsion mechanics and other gait characteristics must be evaluated. This study investigated: (1) the immediate bilateral effects of restraining forces during treadmill walking on propulsive force, braking force, and mechanical work in people post-stroke, and (2) the impact of this manipulation on step length symmetry, single support time symmetry and muscle activity. Additionally, we explored whether these effects vary with gait speed and force magnitude.</div></div><div><h3>Methods</h3><div>13 individuals post-stroke walked on a treadmill at 0.28 m/s and 0.56 m/s while a horizontal restraining force (0 %, 5 % or 10 % of their body weight) was applied to the pelvis. During walking, ground reaction forces and muscle activity of gluteus Medius, rectus Femoris, vastus Medialis, biceps Femoris, tibialis anterior, medial gastrocnemius and soleus were bilaterally recorded</div></div><div><h3>Findings</h3><div>Applying restraining forces up to 10 % of body weight increased propulsive impulse and mechanical work while reducing braking impulse. Although no significant effects were found on step length symmetry or swing phase symmetry, subtle changes in muscle activity were observed when walking with restraining forces</div></div><div><h3>Interpretation</h3><div>Restraining forces up to 10 % of body weight can activate propulsive capacity. Future research should explore how this direct effect translates into long-term training effects.</div></div>","PeriodicalId":50992,"journal":{"name":"Clinical Biomechanics","volume":"130 ","pages":"Article 106664"},"PeriodicalIF":1.4,"publicationDate":"2025-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145050221","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 silico analysis of fixation device strain patterns in the postoperative proximal femur: Effects of bone quality during gait.","authors":"Yogesh Kumaran, Sophia Soehnlen, Christopher Haritos, Sanam Jhaveri, Sudharshan Tripathi, Humza Shaikh, Stephanie Di Stasi, Carmen E Quatman","doi":"10.1016/j.clinbiomech.2025.106724","DOIUrl":"10.1016/j.clinbiomech.2025.106724","url":null,"abstract":"<p><strong>Background: </strong>Proximal femur fracture fixation fundamentally alters load transfer, which can trigger adverse bone remodeling, particularly after healing in osteoporotic bone. While previous studies have focused on early fixation stability or acute fracture healing, the long-term mechanical environment after fracture consolidation remains poorly understood. This study examines implant-specific strain behavior in the post-healed state to identify patterns that may predispose to late-stage implant failure or remodeling.</p><p><strong>Methods: </strong>Subject-specific finite-element models were created from CT scans of a healthy 22-year-old and an osteoporotic 90-year-old female. Cannulated screws (CS), a dynamic hip screw (DHS), and a femoral neck system (FNS) were virtually implanted in each model and subjected to simulated gait loading. Maximum implant stresses and regional principal strains across the proximal femur were quantified throughout the stance phase.</p><p><strong>Findings: </strong>The FNS demonstrated the highest maximum von Mises stresses in both normal and osteoporotic bone, notably at the anti-rotation screw and bolt interface. In osteoporotic bone, the FNS exhibited significantly higher tensile (mean 0.36 % ± 0.22 %) and compressive strains (mean - 0.41 % ± 0.28 %) compared to CS and DHS implants, while in normal bone, FNS strains were comparable to intact femur strains. The CS model showed reduced peak strains and stresses throughout the gait cycle compared to DHS and FNS.</p><p><strong>Interpretation: </strong>This study provides a comparative assessment of healed-state strain distributions across common fixation constructs. By characterizing these environments, these data establish a biomechanical framework and highlight the interplay between implant design and bone quality. Further population-based studies are required to refine implant selection.</p>","PeriodicalId":50992,"journal":{"name":"Clinical Biomechanics","volume":" ","pages":"106724"},"PeriodicalIF":1.4,"publicationDate":"2025-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12935158/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145679559","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}

{"title":"Dual-energy X-ray absorptiometry based biofidelic finite element models for simulating falls to the hip: Impact of trochanteric soft tissue thickness on fracture risk.","authors":"Dheeraj Jha, Anitha D Praveen, Alexander Baker, Anita Fung, Vee San Cheong, Preeti Gupta, Ecosse L Lamoureux, Namki Hong, Yumie Rhee, Vanessa Jean Wen Koh, Halldór Pálsson, William R Taylor, Angelique Wei-Ming Chan, Stephen J Ferguson, Benedikt Helgason","doi":"10.1016/j.clinbiomech.2025.106720","DOIUrl":"https://doi.org/10.1016/j.clinbiomech.2025.106720","url":null,"abstract":"<p><strong>Background: </strong>We predicted the fracture outcomes of simulated falls from standing height using biofidelic finite element models of older adults in Singapore. We further investigated the influence of trochanteric soft tissue thickness, measured from scans and equations estimating standing trochanteric soft tissue thickness from DXA and BMI, on predicted fracture outcomes.</p><p><strong>Methods: </strong>Biofidelic finite element models were built using DXA scans from 280 older Singaporean adults enrolled in the Targeted Assessment and Recruitment of Geriatrics for Effective Fall Prevention Treatments study. Models were created using different trochanteric soft tissue thickness: measured from 3D optical scans in standing (reference), measured from whole-body DXA, estimated from whole-body DXA, and estimated from BMI. Predicted fracture outcomes from sideways falls were compared across these models.</p><p><strong>Findings: </strong>The number of predicted hip fractures was higher among Chinese participants compared to Indians (females: 2.4×, males: 2.3×) and Malays (females: 2.5×, males: 1.3×). Trochanteric soft tissue thickness was the dominant factor influencing impact force and force attenuation at the greater trochanter. The whole-body DXA model had a 26 % false prediction rate compared to the reference model, while the models using estimated values from whole-body DXA and BMI had false prediction rates of 1 % and 9 %, respectively.</p><p><strong>Interpretation: </strong>Biofidelic finite element models built using image data captures population-based differences in hip fracture risk for the three main ethnic groups in Singapore. In the absence of 3D optical scans, predicting soft tissue shapes based on whole-body DXA scans, commonly available in clinical practice, yields similar fracture predictions based on simulated falls.</p>","PeriodicalId":50992,"journal":{"name":"Clinical Biomechanics","volume":" ","pages":"106720"},"PeriodicalIF":1.4,"publicationDate":"2025-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145642344","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 silico clinical trial to predict the efficacy of alendronate for preventing hip fractures.","authors":"Sara Oliviero, Giacomo Savelli, Marco Viceconti, Antonino A La Mattina","doi":"10.1016/j.clinbiomech.2025.106689","DOIUrl":"https://doi.org/10.1016/j.clinbiomech.2025.106689","url":null,"abstract":"<p><strong>Background: </strong>Hip fractures associated with osteoporosis are a major healthcare concern. Existing drugs have limited efficacy in reducing hip fractures. However, clinical trials require large cohorts and lengthy follow-up. Computational models could potentially improve the development of more effective treatments. The aim of this study was to validate an In Silico Trial (BoneStrength) by reproducing a published clinical trial on the efficacy of alendronate. The predicted number of fractures was compared to the clinical data.</p><p><strong>Methods: </strong>A statistical atlas was used to generate a virtual cohort (N = 1050), with baseline characteristics replicating the reference trial. Treatment with alendronate was simulated by increasing bone mineral density over time. Fracture incidence was predicted using a Markov Chain process. The impact force associated with each fall was estimated with a multiscale stochastic model. Finite Element models were used to predict femur strength. A patient was considered fractured when the impact force exceeded femur strength.</p><p><strong>Findings: </strong>In the placebo group, virtual patients (N = 1050) experienced 15 ± 4 hip fractures in four years, whereas in the reference trial 24 occurred for 2218 patients (11 for 1050 patients). In the alendronate arm, fractures were reduced to 10 ± 3 in the virtual cohort, while 19 were observed in 2214 patients (9 for 1050 patients).</p><p><strong>Interpretation: </strong>The distribution of hip fracture incidence predicted by the model included the clinical data for both groups. This In Silico trial can be applied in the future to improve clinical trial design and drug development, enabling a virtual pathway to the efficacy assessment of bone drugs.</p>","PeriodicalId":50992,"journal":{"name":"Clinical Biomechanics","volume":" ","pages":"106689"},"PeriodicalIF":1.4,"publicationDate":"2025-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145524828","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":"Porcine tendons as surrogates for human semitendinosus tendons – A biomechanical study","authors":"Salim Youssef ,&nbsp;Benjamin Fischer ,&nbsp;Garen-Ohan Gregorian ,&nbsp;Toni Wendler ,&nbsp;Philipp Rolzhäuser ,&nbsp;Ahmad Hamedy ,&nbsp;Pierre Hepp ,&nbsp;Stefan Schleifenbaum ,&nbsp;Peter Melcher ,&nbsp;Yasmin Youssef ,&nbsp;Jan Theopold","doi":"10.1016/j.clinbiomech.2025.106655","DOIUrl":"10.1016/j.clinbiomech.2025.106655","url":null,"abstract":"<div><h3>Background</h3><div>Porcine tendons are frequently used as surrogates for human semitendinosus tendons in biomechanical studies, yet their comparability remains unexplored.</div></div><div><h3>Methods</h3><div>This study evaluates and compares the morphological and biomechanical properties of different porcine tendons (foreleg-extensors (<em>n</em> = 10), foreleg-flexors (n = 10), hindleg-extensors (n = 10) and hindleg-flexors (n = 10)) with those of human semitendinosus tendons (<em>n</em> = 13). Tendon length and cross-sectional area were measured, and maximum load, tensile strength, stiffness, and elastic modulus were determined using uniaxial testing. Statistical analysis was performed using the Kruskal-Wallis test followed by Dunn's post hoc test.</div></div><div><h3>Findings</h3><div>Human semitendinosus tendons (26.59 cm, 18.98 mm²) exhibited the highest tensile strength (38.64 MPa) and an elastic modulus of 518.27 MPa. Porcine foreleg-extensors had comparable cross-sectional area (14.99 mm²), tensile strength (32.26 MPa), and elastic modulus (550.96 MPa) but were shorter (23.08 cm). Hindleg-flexors showed a similar length (25.81 cm) and elastic modulus (610.19 MPa) but lower tensile strength (28.13 MPa) and a substantially larger cross-sectional area (71.91 mm²). Hindleg-extensors were shorter (22.62 cm) with smaller cross-sectional area (11.20 mm²) but exhibited tensile strength (38.82 MPa) and elastic modulus (668.83 MPa) similar to those of the human tendons. Foreleg-flexors were shortest (17.07 cm), with the largest cross-sectional area (112.74 mm²), lowest tensile strength (18.82 MPa), and elastic modulus (155.70 MPa).</div></div><div><h3>Interpretation</h3><div>Despite differences in morphology, the material properties of tendons were largely consistent. Foreleg-extensors were identified as the most suitable semitendinosus surrogates due to their comparable material and morphological properties. Due to their distinct morphology, foreleg-flexors tendons are least suitable.</div></div>","PeriodicalId":50992,"journal":{"name":"Clinical Biomechanics","volume":"129 ","pages":"Article 106655"},"PeriodicalIF":1.4,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144890709","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":"Reliability and educational potential of a computational model of vacuum-assisted delivery on a birth simulator","authors":"Y. Vallet ,&nbsp;J. Lefebvre ,&nbsp;C. Bertholdt ,&nbsp;A. Baldit ,&nbsp;R. Rahouadj ,&nbsp;O. Morel ,&nbsp;C. Laurent","doi":"10.1016/j.clinbiomech.2025.106633","DOIUrl":"10.1016/j.clinbiomech.2025.106633","url":null,"abstract":"<div><h3>Background</h3><div>Vacuum-assisted delivery is widely used in operative vaginal deliveries but carries a risk of rare yet severe complications. Computational simulations offer a promising way to improve our understanding of the mechanisms underlying these injuries. However, these simulations remain insufficiently validated experimentally and have not yet been applied to vacuum extraction. This study aims to evaluate the reliability of these methods using a simplified training dummy and to demonstrate their educational potential by analyzing key parameters of the clinical procedure.</div></div><div><h3>Methods</h3><div>Reliability was assessed using a birth simulator by comparing predicted extraction forces (derived from computational simulations using the finite element method) with experimental measurements obtained from vacuum extractions performed using a Kiwi® cup on a training dummy mounted on a force platform (<em>N</em> = 16). The model was then used to investigate how prescribed trajectory, suction cup position, and fetal head size influence both extraction forces and maximum strain in external deformable tissues.</div></div><div><h3>Findings</h3><div>The maximal extraction force predicted by computational simulations was 42.3 N, while it ranged between 46.1 N and 85.3 N (mean 67.5 ± 13.3 N, <em>N</em> = 16) experimentally. Similar trends in the force components were obtained through the whole extraction trajectory. The most downward trajectory was shown to minimize extraction force and maximal perineal tissue strain, as well as achieving the most occipital cup placement, in line with reported recommendations.</div></div><div><h3>Interpretation</h3><div>Results demonstrated that computational simulations could reliably predict extraction forces during birth simulations on a training dummy, while also revealing associated uncertainties and a tendency to underestimate extraction forces. Simulations of various scenarios provided valuable insights that could enhance obstetrics training and complement existing methods. Although not intended for direct clinical translation, this study evaluates the relevance of computational modelling in a controlled, simulation-based training context.</div></div>","PeriodicalId":50992,"journal":{"name":"Clinical Biomechanics","volume":"129 ","pages":"Article 106633"},"PeriodicalIF":1.4,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144913697","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":"Pathways of load transfer in custom accommodative insoles for people with diabetes","authors":"Dylan J. Heino ,&nbsp;Scott Telfer ,&nbsp;Kimberly A. Nickerson ,&nbsp;Christina Carranza ,&nbsp;Mathew Sunil Varre ,&nbsp;Avocet Nagle-Christensen ,&nbsp;William R. Ledoux ,&nbsp;Brittney C. Muir","doi":"10.1016/j.clinbiomech.2025.106645","DOIUrl":"10.1016/j.clinbiomech.2025.106645","url":null,"abstract":"<div><h3>Background</h3><div>Custom accommodative insoles help reduce plantar pressures in people with diabetes who are at risk of developing foot ulcers. We have developed 3D printed custom accommodative insoles with patient-specific geometry and material properties that improve offloading performance compared to traditional insoles. While effective at offloading forefoot pressure, their load redistribution mechanisms across the full foot remain unclear. The purpose of this study is to compare the load redistribution mechanisms and pathways across nine plantar regions between standard and 3D printed insoles using a load transfer algorithm.</div></div><div><h3>Methods</h3><div>Twenty-six feet from 17 individuals with diabetes and high forefoot plantar pressure were included. Each participant received three pairs of custom accommodative insoles: standard of care, finite element optimized 3D printed, and pressure-based 3D printed. Peak plantar pressure and force-time-integral were recorded during walking, and a load transfer algorithm was used to map redistribution.</div></div><div><h3>Findings</h3><div>The main pathway of load transfer across all insoles was from the metatarsal heads to the midfoot, particularly from the first metatarsal head to the medial midfoot. The finite element optimized 3D printed custom accommodative insoles had the largest load transfers away from the metatarsal heads compared to the other insole conditions.</div></div><div><h3>Interpretation</h3><div>Design elements like arch height, metatarsal bars, and offloading zones influenced load transfer pathways. These results underscore the potential of custom accommodative insole designs to offload high-risk areas and adds an additional perspective to quantify insole performance, though subject-specific variability remains an important factor.</div></div>","PeriodicalId":50992,"journal":{"name":"Clinical Biomechanics","volume":"129 ","pages":"Article 106645"},"PeriodicalIF":1.4,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144863875","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":"Differences in kinetics and kinematics of sit-to-stand between independent and dependent post-stroke individuals.","authors":"Naoyuki Motojima, Sumiko Yamamoto, Toshiyuki Kohno","doi":"10.1016/j.clinbiomech.2025.106636","DOIUrl":"10.1016/j.clinbiomech.2025.106636","url":null,"abstract":"<p><strong>Background: </strong>The sit-to-stand movement is important for the rehabilitation of individuals with poststroke hemiplegia. This study aimed to clarify the variation in kinetic and kinematic characteristics of sit-to-stand movements according to differences in the ability of individuals with poststroke hemiplegia.</p><p><strong>Methods: </strong>Twenty five individuals in the subacute phase of stroke-induced hemiplegia, who needed assistance to practice the sit-to-stand movement (dependent group) and 25 individuals in the subacute phase of stroke-induced hemiplegia who could stand up independently (independent group) were selected for the study. To ensure a fair comparison, the two groups were matched for age, sex, body size, and the paretic side. The sit-to-stand movement was quantified using a three-dimensional motion-analysis system, and the resulting kinetics, kinematics of thorax, pelvis and lower limb, and weight bearing were compared.</p><p><strong>Findings: </strong>The dependent group exhibited significantly reduced hip flexion torque and significantly greater thoracic and pelvic anterior tilt prior to seat-off than the independent group. After seat-off, the dependent group exhibited significantly reduced paretic knee extension torque and significantly greater weight bearing on the nonparetic side, along with significantly elevated hip extension torque on the paretic and non-paretic sides, in comparison to the independent group.</p><p><strong>Interpretation: </strong>The kinetic and kinematic characteristics of the sit-to-stand maneuver before seat-off in the dependent group poststroke differ from those in the independent poststroke individuals, as previously reported. These findings also suggest that weight-bearing on the non- paretic side is key in the sit-to-stand movement of dependent individuals.</p>","PeriodicalId":50992,"journal":{"name":"Clinical Biomechanics","volume":"129 ","pages":"106636"},"PeriodicalIF":1.4,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144800878","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 comparison between manual and automated event detection for shuffle, deceleration and run cut tasks using motion capture.","authors":"Alex M Loewen, Jan Karel Petric, Hannah L Olander, Joshua Riesenberg, Sophia Ulman","doi":"10.1016/j.clinbiomech.2025.106644","DOIUrl":"10.1016/j.clinbiomech.2025.106644","url":null,"abstract":"<p><strong>Background: </strong>Increased adolescent sports participation lead to a rise in sports-related injuries. These injuries impact athletes' health and performance, necessitating improved injury prevention methods. The shuffle, deceleration, and run cut tasks are commonly used in injury prevention protocols to elicit improper movement mechanics. Recent literature examined the use of an automated event detection algorithm to improve the accuracy of 3-dimensional motion capture data processing techniques. Manual and automated event detection methods were compared during these tasks in two different groups of participants.</p><p><strong>Methods: </strong>Thirty healthy controls and thirty adolescents following anterior cruciate ligament reconstruction, performed a shuffle, deceleration, and run-cut task in a motion capture lab. Specific timepoints of the tasks were manually identified by two raters and automatically detected by custom MATLAB algorithms. Intra- and inter-rater reliability, differences in event timings, and task performance were compared.</p><p><strong>Findings: </strong>Significant differences in event timings were found between manual and automated methods, particularly with events identifying the lateral, forward, or vertical position of the participant with the absolute difference ranging from 4.7 to 13.5 frames across all three tasks. The identification of the first and last timepoints the foot is contacting the ground were similar between methods.</p><p><strong>Interpretation: </strong>The results of this study indicate that automated event detection is a more reliable method of identifying timepoints assessing participant's movement, highlighting its value in clinical and research settings. Automated event detection may improve injury risk assessments by minimizing user variability and offering consistent event identification across diverse movement tasks.</p>","PeriodicalId":50992,"journal":{"name":"Clinical Biomechanics","volume":"129 ","pages":"106644"},"PeriodicalIF":1.4,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144796047","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":"How does the stem design affect the degree of freedom of the stem version and position? A computer simulation study","authors":"Shotaro Kawamura ,&nbsp;Daisuke Hara ,&nbsp;Satoshi Hamai ,&nbsp;Goro Motomura ,&nbsp;Shinya Kawahara ,&nbsp;Taishi Sato ,&nbsp;Ryosuke Yamaguchi ,&nbsp;Takeshi Utsunomiya ,&nbsp;Yasuharu Nakashima","doi":"10.1016/j.clinbiomech.2025.106628","DOIUrl":"10.1016/j.clinbiomech.2025.106628","url":null,"abstract":"<div><h3>Background</h3><div>Controlling stem anteversion is crucial in total hip arthroplasty to prevent prosthetic impingement. The degree of freedom in stem version varies depending on the stem design. However, few studies have quantified the version freedom across different stem designs. This study aimed to quantify the differences in the version freedom and position according to stem version changes between tapered-wedge and fit-and-fill stems.</div></div><div><h3>Methods</h3><div>Fifty-one hips were examined using preoperative CT. Three-dimensional templating was performed using tapered-wedge and fit-and-fill stems. The difference between the maximum and minimum stem anteversions was defined as the version freedom. Stem alignment changes in the coronal and sagittal planes and stem depth changes according to the changes in stem version were examined. Changes in the version with respect to the native femoral version were also compared.</div></div><div><h3>Findings</h3><div>The mean version freedom for the tapered-wedge stem (21.7°) was significantly greater than that for the fit-and-fill stem (9.8°, <em>P</em> &lt; 0.0001). The stem alignment changes of the tapered-wedge stem in the coronal and sagittal planes were significantly greater than those of the fit-and-fill stem, with no significant difference in the stem depth change. The version freedom significantly correlated with stem alignment changes. Both stem designs more easily increased stem anteversion but were more limited in decreasing it relative to the native femoral anteversion.</div></div><div><h3>Interpretation</h3><div>Stem design affects the version freedom. Increased adjustability of the tapered-wedge stem may improve implant positioning. Meticulous surgical planning and precise intraoperative control remain crucial to achieving target anteversion and ensuring optimal long-term outcomes.</div></div>","PeriodicalId":50992,"journal":{"name":"Clinical Biomechanics","volume":"129 ","pages":"Article 106628"},"PeriodicalIF":1.4,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144880203","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}