Jin Nie, Xiaojiang Lv, Xing Huang, Kui Li, Guibing Li
Purpose: The purpose of the current study is to understand pedestrian kinematics, biomechanical response and injury risk in high speed vehicle crashes.
Methods: Vehicle-to-pedestrian crashes at the impact speeds of 40 km/h (reference set) and 70 km/h (analysis set) were simulated employing FE models of a sedan front and an SUV front together with a pedestrian FE model developed using hollow structures. The predictions from crash simulations of different vehicle types and impact speeds were compared and analyzed.
Results: In crashes at 70 km/h, pedestrian head-vehicle contact velocity is by about 20-30% higher than the vehicle impact speed, the peak head angular velocity exceeds 100 rad/s and is close to the instant of head-vehicle contact, brain strain appears two peaks and the second peak (after head contact) is obviously higher than the first (before head contact), and AIS4+ head injury risk is above 50%, excessive thorax compression induces rib fractures and lung compression, both sedan and SUV cases show a high risk (>70%) of AIS3 + thorax injury, and the risk of AIS4 + thorax injury is lower than 40% in the sedan case and higher than 50% for the SUV case.
Conclusions: Pedestrians in vehicle crashes at 70 km/h have a higher AIS3 + /AIS4 + head and thorax injury risk, high vehicle impact speed is more easily to induce a high head angular velocity at the instant of head-vehicle contact, brain strain is strongly associated with the combined effect of head rotational velocity and acceleration, and pedestrian thorax injury risk is more sensitive to vehicle impact speed than the head.
目的：本研究旨在了解高速车辆碰撞中的行人运动学、生物力学反应和受伤风险：方法：使用轿车前部和越野车前部的 FE 模型以及使用空心结构开发的行人 FE 模型，模拟了撞击速度为 40 km/h （参考集）和 70 km/h （分析集）的车辆与行人碰撞。对不同车辆类型和撞击速度下的碰撞模拟预测结果进行了比较和分析：结果：在时速 70 公里的碰撞中，行人头车接触速度比车辆撞击速度高出约 20-30%，头部角速度峰值超过 100 弧度/秒，且接近头车接触瞬间，脑应变出现两个峰值，且第二个峰值（头部接触后）明显高于第一个峰值（头部接触前）、过度的胸部挤压会导致肋骨骨折和肺部挤压，轿车和 SUV 案例均显示出 AIS3 + 胸部损伤的高风险（>70%），轿车案例中 AIS4 + 胸部损伤的风险低于 40%，而 SUV 案例中 AIS4 + 胸部损伤的风险高于 50%。结论在时速 70 公里的车辆碰撞中，行人的 AIS3 + /AIS4 + 头部和胸部损伤风险较高，高车辆撞击速度更容易在头部与车辆接触的瞬间引起较高的头部角速度，脑损伤与头部旋转速度和加速度的综合效应密切相关，行人胸部损伤风险对车辆撞击速度的敏感性高于头部。
{"title":"Pedestrian dynamic response and injury risk in high speed vehicle crashes.","authors":"Jin Nie, Xiaojiang Lv, Xing Huang, Kui Li, Guibing Li","doi":"","DOIUrl":"","url":null,"abstract":"<p><strong>Purpose: </strong>The purpose of the current study is to understand pedestrian kinematics, biomechanical response and injury risk in high speed vehicle crashes.</p><p><strong>Methods: </strong>Vehicle-to-pedestrian crashes at the impact speeds of 40 km/h (reference set) and 70 km/h (analysis set) were simulated employing FE models of a sedan front and an SUV front together with a pedestrian FE model developed using hollow structures. The predictions from crash simulations of different vehicle types and impact speeds were compared and analyzed.</p><p><strong>Results: </strong>In crashes at 70 km/h, pedestrian head-vehicle contact velocity is by about 20-30% higher than the vehicle impact speed, the peak head angular velocity exceeds 100 rad/s and is close to the instant of head-vehicle contact, brain strain appears two peaks and the second peak (after head contact) is obviously higher than the first (before head contact), and AIS4+ head injury risk is above 50%, excessive thorax compression induces rib fractures and lung compression, both sedan and SUV cases show a high risk (>70%) of AIS3 + thorax injury, and the risk of AIS4 + thorax injury is lower than 40% in the sedan case and higher than 50% for the SUV case.</p><p><strong>Conclusions: </strong>Pedestrians in vehicle crashes at 70 km/h have a higher AIS3 + /AIS4 + head and thorax injury risk, high vehicle impact speed is more easily to induce a high head angular velocity at the instant of head-vehicle contact, brain strain is strongly associated with the combined effect of head rotational velocity and acceleration, and pedestrian thorax injury risk is more sensitive to vehicle impact speed than the head.</p>","PeriodicalId":6897,"journal":{"name":"Acta of bioengineering and biomechanics","volume":"24 3","pages":"57-67"},"PeriodicalIF":1.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139680539","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Julia Lisoń-Kubica, Anna Taratuta, Karolina Goldsztajn, Magdalena Antonowicz, Witold Walke, Aneta Dyner, Marcin Basiaga
The constantly growing need for the use of implants in osteotomy is mainly due to the aging population and the need for long-term use of this type of biomaterials. Improving implant materials requires the selection of appropriate functional properties. Currently used titanium (Ti) alloys, such as Ti6Al4V and Ti6Al7Nb, are being replaced by materials with better biocompatibility, such as vanadium (V) or niobium (Nb), allowing for creation of the so-called new generation alloys. These new alloys, with the incorporation of zirconium (Zr), iron, and tantalum, possess Young's modulus close to that of a bone, which further improves the improves the biomaterial's. biocompatibility. This article describes the atomic layer deposition (ALD) method and its possible applications in the new generation of titanium alloys for biomedical applications. Also, the exemplary results of tin oxide (SnO2) thin coatings deposited by ALD and physical vapor deposition (PVD) methods are presented. This study aimed to evaluate the physicochemical properties of a Ti13Nb13Zr alloy used for elements in the skeletal system. As the temperature and the number of cycles vary, the results demonstrate that the surface area of the samples changes. The uncoated Ti13Nb13Zr alloy exhibits hydrophilic properties. However, all coated specimens improve in this respect and provide improved clinical results. after the applied modification, the samples have a smaller contact angle, but still remain in the range of 0-90°, which makes it possible to conclude that their nature remains hydrophilic. Coating the specimens decreased the mineralization risk of postoperative complications. As a result, the biomaterials demonstrated improved effectiveness, decreased complication indicators, and improved patient well-being.
{"title":"Modern methods of surface modification for new-generation titanium alloys.","authors":"Julia Lisoń-Kubica, Anna Taratuta, Karolina Goldsztajn, Magdalena Antonowicz, Witold Walke, Aneta Dyner, Marcin Basiaga","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>The constantly growing need for the use of implants in osteotomy is mainly due to the aging population and the need for long-term use of this type of biomaterials. Improving implant materials requires the selection of appropriate functional properties. Currently used titanium (Ti) alloys, such as Ti6Al4V and Ti6Al7Nb, are being replaced by materials with better biocompatibility, such as vanadium (V) or niobium (Nb), allowing for creation of the so-called new generation alloys. These new alloys, with the incorporation of zirconium (Zr), iron, and tantalum, possess Young's modulus close to that of a bone, which further improves the improves the biomaterial's. biocompatibility. This article describes the atomic layer deposition (ALD) method and its possible applications in the new generation of titanium alloys for biomedical applications. Also, the exemplary results of tin oxide (SnO2) thin coatings deposited by ALD and physical vapor deposition (PVD) methods are presented. This study aimed to evaluate the physicochemical properties of a Ti13Nb13Zr alloy used for elements in the skeletal system. As the temperature and the number of cycles vary, the results demonstrate that the surface area of the samples changes. The uncoated Ti13Nb13Zr alloy exhibits hydrophilic properties. However, all coated specimens improve in this respect and provide improved clinical results. after the applied modification, the samples have a smaller contact angle, but still remain in the range of 0-90°, which makes it possible to conclude that their nature remains hydrophilic. Coating the specimens decreased the mineralization risk of postoperative complications. As a result, the biomaterials demonstrated improved effectiveness, decreased complication indicators, and improved patient well-being.</p>","PeriodicalId":6897,"journal":{"name":"Acta of bioengineering and biomechanics","volume":"24 4","pages":"147-158"},"PeriodicalIF":1.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9673582","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.37190/abb-01945-2021-04
Aneta Bugalska, A. Hadamus, S. Wójtowicz, Anna Daniluk, Karolina Wiaderna, M. Grabowicz
Purpose: The aim of this study was to determine the impact of isometric and isokinetic hip abductor muscle strength on the quality of maintaining static balance in healthy subjects. Methods: The study enrolled 51 healthy women aged 18–25. Balance assessment was carried out according to the M-CTSIB protocol and Single Leg Stance Test (with eyes open and closed) using the Biodex Balance System. An isokinetic evaluation conducted at 30 °/s and an isometric evaluation of the hip abductors were performed with the Humac Norm system. Results: Regression analysis for Sway Index (SW) and Stability Index (ST) in bipedal standing showed a significant importance of the presence of visual feedback (RSW EO = –0.922; p < 0.0001; RST EO = –0.613; p = 0.0493), and unstable surface (RSW US = 1.253; p < 0.0001; RSW US = 2.547; p < 0.0001). Regression analysis for single-leg stance showed correlations between the following indices: overall sway index (OR) in single-leg stance, the antero-posterior (AP) sway index and the medio-lateral (ML) sway index on the one hand and isometric abduction time to peak torque (ROR TPT = 0.769; p = 0.0005; RAP TPT = 0.565; p = 0.008; RML TPT = –1.74; p < 0.05, respectively) as well as the test conditions on the other. Conclusions: Physiological activation of the hip abductors may be important for physiological maintenance of postural balance in young people, in both leg standing as well as in single-leg stance. The present results warrant prospective, randomized studies of larger groups that are diversified with regard to age and gender of the participants.
目的:本研究的目的是确定髋关节外展肌力量对健康受试者保持静态平衡质量的影响。方法:研究招募了51名年龄在18-25岁的健康女性。使用Biodex平衡系统，根据M-CTSIB方案和单腿站立测试(睁眼和闭眼)进行平衡评估。采用Humac Norm系统进行30°/s等速运动评估和髋外展肌等速评估。结果:对两足站立时摇摆指数(SW)和稳定性指数(ST)的回归分析显示，视觉反馈的存在具有显著的重要性(RSW EO = -0.922;P < 0.0001;RST eo = -0.613;p = 0.0493)，不稳定表面(RSW US = 1.253;P < 0.0001;RSW us = 2.547;P < 0.0001)。单腿站立的回归分析显示，单腿站立的整体摇摆指数(OR)、前后摇摆指数(AP)和中外侧摇摆指数(ML)与等轴外展时间至峰值扭矩之间存在相关性(ROR TPT = 0.769;P = 0.0005;Rap TPT = 0.565;P = 0.008;RML TPT = -1.74;P < 0.05)，另一组试验条件差异显著。结论:髋关节外展肌的生理激活可能对年轻人两腿站立和单腿站立时姿势平衡的生理维持很重要。目前的结果保证了前瞻性的、随机的更大群体的研究，这些群体在年龄和性别方面是多样化的。
{"title":"Influence of force-time parameters of hip abductors on maintaining balance in frontal plane in young healthy females","authors":"Aneta Bugalska, A. Hadamus, S. Wójtowicz, Anna Daniluk, Karolina Wiaderna, M. Grabowicz","doi":"10.37190/abb-01945-2021-04","DOIUrl":"https://doi.org/10.37190/abb-01945-2021-04","url":null,"abstract":"Purpose: The aim of this study was to determine the impact of isometric and isokinetic hip abductor muscle strength on the quality of maintaining static balance in healthy subjects. Methods: The study enrolled 51 healthy women aged 18–25. Balance assessment was carried out according to the M-CTSIB protocol and Single Leg Stance Test (with eyes open and closed) using the Biodex Balance System. An isokinetic evaluation conducted at 30 °/s and an isometric evaluation of the hip abductors were performed with the Humac Norm system. Results: Regression analysis for Sway Index (SW) and Stability Index (ST) in bipedal standing showed a significant importance of the presence of visual feedback (RSW EO = –0.922; p < 0.0001; RST EO = –0.613; p = 0.0493), and unstable surface (RSW US = 1.253; p < 0.0001; RSW US = 2.547; p < 0.0001). Regression analysis for single-leg stance showed correlations between the following indices: overall sway index (OR) in single-leg stance, the antero-posterior (AP) sway index and the medio-lateral (ML) sway index on the one hand and isometric abduction time to peak torque (ROR TPT = 0.769; p = 0.0005; RAP TPT = 0.565; p = 0.008; RML TPT = –1.74; p < 0.05, respectively) as well as the test conditions on the other. Conclusions: Physiological activation of the hip abductors may be important for physiological maintenance of postural balance in young people, in both leg standing as well as in single-leg stance. The present results warrant prospective, randomized studies of larger groups that are diversified with regard to age and gender of the participants.","PeriodicalId":6897,"journal":{"name":"Acta of bioengineering and biomechanics","volume":"81 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69999249","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.37190/abb-01989-2021-02
M. Kopernik, Karina Dyrda, Przemyslaw Kurtyka, R. Major
Purpose: The goal of the present study was the development of discrete phase model to simulate the phenomenon of backfilling a morphologically complex surface by red blood cells (RBCs) in a flow microchannel and to anticipate the conditions of forming a pseudointima. The objective of the experimental studies that inspired the development of the simulation was to create a surface that stimulates the formation of the pseudointima layer. Methods: The finite volume method (FVM) and discrete particle method (DPM) were applied to develop the target model. In addition, a mixture model and a roughness model of bottom layer were tested in the present study to show their influence on simulation the phenomenon of backfilling a morphologically complex surface by RBCs in a flow microchannel. Results: Numerical models were developed including: a) FVM models to compare the effect of applying boundary conditions with/without roughness and cubes, as well as the analysis of their influence on blood velocity and shear stress; b) mixture models to compare the effect of applying different boundary conditions and cubes on computed results; c) DPM models to compare the effect of applying and not applying roughness as a boundary condition; d) DPM models with a morphologically complex surface and RBCs collisions to present RBCs concentration, velocity and time distributions during flow in a channel. Conclusions: The analysis carried out for the developed numerical models indicates that DPM model with cubes computes the best results. It also shows the backfilling of a morphologically complex surface of the bottom microchannel with RBCs.
{"title":"Discrete phase model of blood flow in a roughness microchannel simulating the formation of pseudointima","authors":"M. Kopernik, Karina Dyrda, Przemyslaw Kurtyka, R. Major","doi":"10.37190/abb-01989-2021-02","DOIUrl":"https://doi.org/10.37190/abb-01989-2021-02","url":null,"abstract":"Purpose: The goal of the present study was the development of discrete phase model to simulate the phenomenon of backfilling a morphologically complex surface by red blood cells (RBCs) in a flow microchannel and to anticipate the conditions of forming a pseudointima. The objective of the experimental studies that inspired the development of the simulation was to create a surface that stimulates the formation of the pseudointima layer. Methods: The finite volume method (FVM) and discrete particle method (DPM) were applied to develop the target model. In addition, a mixture model and a roughness model of bottom layer were tested in the present study to show their influence on simulation the phenomenon of backfilling a morphologically complex surface by RBCs in a flow microchannel. Results: Numerical models were developed including: a) FVM models to compare the effect of applying boundary conditions with/without roughness and cubes, as well as the analysis of their influence on blood velocity and shear stress; b) mixture models to compare the effect of applying different boundary conditions and cubes on computed results; c) DPM models to compare the effect of applying and not applying roughness as a boundary condition; d) DPM models with a morphologically complex surface and RBCs collisions to present RBCs concentration, velocity and time distributions during flow in a channel. Conclusions: The analysis carried out for the developed numerical models indicates that DPM model with cubes computes the best results. It also shows the backfilling of a morphologically complex surface of the bottom microchannel with RBCs.","PeriodicalId":6897,"journal":{"name":"Acta of bioengineering and biomechanics","volume":"1 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69999280","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.37190/abb-02002-2021-02
A. Halinski, Kamila Pasik, A. Haliński, Paweł Haliński, A. Trinchieri, N. Buchholz, K. Arkusz
Purpose: The aim of this study was to determine the affinity to crystal, calculi and biofilm deposition on ureteral double-J stents (DJ stents) after ureterorenoscopic–lithotripsy procedure (URS-L). The analysis was performed in two aspects: to determine which material used for fabricating ureteral stents promotes encrustation and which part of the DJ stents is the most vulnerable for blockage. Methods: One hundred and twenty patients with an indwelling DJ stent duration between 7 and 78 days were included in this study. The encrustation of DJ stents was characterized by scanning electron microscopy (SEM), and the mechanical properties of DJ stents were examined using the standard MTS Micro Bionix tensile test. Results: This study showed that polyurethane catheters have a much higher affinity for encrustation than styrene/ethylene/butylene block copolymer. Obtained results indicated the proximal (renal pelvis) and distal (urinary bladder) part is the most susceptible to post-URS-L fragments and urea salt deposition. Both the DJ ureteral stents’ outer and inner surfaces were completely covered even after 7 days of implantation. Conclusions: Performed analysis pointed out that polyurethane DJ stents have a much higher affinity for encrustation of calculi and NaCl crystals compared to the silicone-based copolymer. The surface of the ureteral stents needs improvement to minimize salt and kidney stone deposition, causing pre-biofilm formation and the occurrence of defects and cracks.
{"title":"Encrustation of the ureteral double-J Stents made of styrene/ethylene/butylene and polyurethane before and after implantation","authors":"A. Halinski, Kamila Pasik, A. Haliński, Paweł Haliński, A. Trinchieri, N. Buchholz, K. Arkusz","doi":"10.37190/abb-02002-2021-02","DOIUrl":"https://doi.org/10.37190/abb-02002-2021-02","url":null,"abstract":"Purpose: The aim of this study was to determine the affinity to crystal, calculi and biofilm deposition on ureteral double-J stents (DJ stents) after ureterorenoscopic–lithotripsy procedure (URS-L). The analysis was performed in two aspects: to determine which material used for fabricating ureteral stents promotes encrustation and which part of the DJ stents is the most vulnerable for blockage. Methods: One hundred and twenty patients with an indwelling DJ stent duration between 7 and 78 days were included in this study. The encrustation of DJ stents was characterized by scanning electron microscopy (SEM), and the mechanical properties of DJ stents were examined using the standard MTS Micro Bionix tensile test. Results: This study showed that polyurethane catheters have a much higher affinity for encrustation than styrene/ethylene/butylene block copolymer. Obtained results indicated the proximal (renal pelvis) and distal (urinary bladder) part is the most susceptible to post-URS-L fragments and urea salt deposition. Both the DJ ureteral stents’ outer and inner surfaces were completely covered even after 7 days of implantation. Conclusions: Performed analysis pointed out that polyurethane DJ stents have a much higher affinity for encrustation of calculi and NaCl crystals compared to the silicone-based copolymer. The surface of the ureteral stents needs improvement to minimize salt and kidney stone deposition, causing pre-biofilm formation and the occurrence of defects and cracks.","PeriodicalId":6897,"journal":{"name":"Acta of bioengineering and biomechanics","volume":"93 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69999466","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.37190/abb-01978-2021-02
Karolina Jasiurkowska, J. Biezynski, A. Nikodem, J. Filipiak
Purpose: Bone fractures are one of the most commonly seen problems in veterinary traumatology. The authors of this study strive to find a new intramedullary nail, which is intended for treating femoral bone fractures for canine patients. The purpose of this study was to analyze biomechanical parameters of the intramedullary nails, which use a new bolt system concept. Methods: Dissected femoral bones of a large breed dog were cut in order to simulate interfragmentary gap, and then the bones were stabilized using intramedullary nail with locking bolts. Bone-nail systems were subjected to cyclic loading using force which corresponds to the load on the femoral bone in the first few days after surgery. Micro-CT scans were taken of the bone samples around implant in order to determine deformation and structural parameters of bone tissue. Results: The calculation of the bone-nail system stiffness was done through analysis of the force displacement curves recorded during experimental studies. Using monocortical locking bolts resulted in smaller stiffness of the bone-nail system than using bicortical locking bolts. Conclusions: The results obtained in this study can indicate that the intramedullary nail could work well when used for treatment of bone fractures in dogs. The authors focused on using monocortical bolts which provides good stability and adequate biomechanical environment. Described fixation method is easily adjustable to a particular patient individual parameters.
{"title":"Influence of the intramedullary nail locking method on the stiffness of the bone-implant system","authors":"Karolina Jasiurkowska, J. Biezynski, A. Nikodem, J. Filipiak","doi":"10.37190/abb-01978-2021-02","DOIUrl":"https://doi.org/10.37190/abb-01978-2021-02","url":null,"abstract":"Purpose: Bone fractures are one of the most commonly seen problems in veterinary traumatology. The authors of this study strive to find a new intramedullary nail, which is intended for treating femoral bone fractures for canine patients. The purpose of this study was to analyze biomechanical parameters of the intramedullary nails, which use a new bolt system concept. Methods: Dissected femoral bones of a large breed dog were cut in order to simulate interfragmentary gap, and then the bones were stabilized using intramedullary nail with locking bolts. Bone-nail systems were subjected to cyclic loading using force which corresponds to the load on the femoral bone in the first few days after surgery. Micro-CT scans were taken of the bone samples around implant in order to determine deformation and structural parameters of bone tissue. Results: The calculation of the bone-nail system stiffness was done through analysis of the force displacement curves recorded during experimental studies. Using monocortical locking bolts resulted in smaller stiffness of the bone-nail system than using bicortical locking bolts. Conclusions: The results obtained in this study can indicate that the intramedullary nail could work well when used for treatment of bone fractures in dogs. The authors focused on using monocortical bolts which provides good stability and adequate biomechanical environment. Described fixation method is easily adjustable to a particular patient individual parameters.","PeriodicalId":6897,"journal":{"name":"Acta of bioengineering and biomechanics","volume":"1 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69999670","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.37190/abb-02105-2022-02
Jarosław Jaszczur-Nowicki, A. M. Hasiuk, R. Podstawski, Małgorzata Potocka-Mitan, D. Ambrozy, Jacek Perliński, B. Ružbarská, Joanna M. Bukowska
Purpose The aim of this study was to assess the biomechanics of the foot in beauty pageant contestants wearing shoes that increase calcaneal height. Plantar pressure distribution and postural balance were examined in women after one hour of wearing high-heeled shoes. Methods Foot arch measurements were conducted using EPSR1 mats. Based on these measurements, 18 of the 19 tested women were diagnosed with significant pes cavus. Results The experiment revealed a significant reduction in the excessively high metatarsal arch of both feet. The mean load on the metatarsus measured at rest was 0.0% in both feet, and it increased by 0.6% in the left leg (p ≤ 0.022; Z = 2.293) and by 2.7% in the right leg (p ≤ 0.023; Z = 2.271). These results suggest that excessive stretching of the plantar fascia and impaired function of the short muscles of the foot lead to a temporary reduction in the arch of the foot. This phenomenon can be compared to stretching a bowstring and its return to the shortest length under static conditions. A statistical analysis of the results of stabilographic measurements revealed significant changes only in the left foot barycenter. An analysis of the ability to maintain postural balance revealed that the observed changes contributed to postural destabilization at p ≤ 0.011 and Z = 2.535. Conclusions Further research involving electromyography tests is needed to examine plantar muscle tension during isotonic contractions. The duration of the exercise-induced reduction in pes cavus should also be determined for therapeutic purposes.
{"title":"Plantar Pressure Distribution and Postural Balance in Beauty Pageant Contestants Before and After Wearing High-Heeled Shoes","authors":"Jarosław Jaszczur-Nowicki, A. M. Hasiuk, R. Podstawski, Małgorzata Potocka-Mitan, D. Ambrozy, Jacek Perliński, B. Ružbarská, Joanna M. Bukowska","doi":"10.37190/abb-02105-2022-02","DOIUrl":"https://doi.org/10.37190/abb-02105-2022-02","url":null,"abstract":"Purpose The aim of this study was to assess the biomechanics of the foot in beauty pageant contestants wearing shoes that increase calcaneal height. Plantar pressure distribution and postural balance were examined in women after one hour of wearing high-heeled shoes. Methods Foot arch measurements were conducted using EPSR1 mats. Based on these measurements, 18 of the 19 tested women were diagnosed with significant pes cavus. Results The experiment revealed a significant reduction in the excessively high metatarsal arch of both feet. The mean load on the metatarsus measured at rest was 0.0% in both feet, and it increased by 0.6% in the left leg (p ≤ 0.022; Z = 2.293) and by 2.7% in the right leg (p ≤ 0.023; Z = 2.271). These results suggest that excessive stretching of the plantar fascia and impaired function of the short muscles of the foot lead to a temporary reduction in the arch of the foot. This phenomenon can be compared to stretching a bowstring and its return to the shortest length under static conditions. A statistical analysis of the results of stabilographic measurements revealed significant changes only in the left foot barycenter. An analysis of the ability to maintain postural balance revealed that the observed changes contributed to postural destabilization at p ≤ 0.011 and Z = 2.535. Conclusions Further research involving electromyography tests is needed to examine plantar muscle tension during isotonic contractions. The duration of the exercise-induced reduction in pes cavus should also be determined for therapeutic purposes.","PeriodicalId":6897,"journal":{"name":"Acta of bioengineering and biomechanics","volume":"1 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69999970","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ryo Tanaka, Hungu Jung, Shunsuke Yamashina, Y U Inoue, Rinna Nakamura, Haruki Toda, Takeshi Imura, Hiroyuki Tamura
Purpose: Gait changes are more prominently observed in older adults than in young adults, especially in kinematics of lower extremities and trunk. These changes can result in incidental falls during gait, possibly leading to inability to perform activities of daily living independently. This study aimed to investigate the effect of gender and age on gait changes, such as spatiotemporal parameters and peak joint angles in lower extremities and trunk during gait.
Methods: A total of 387 participants (223 women) were included. The Microsoft Kinect V2 sensor was used to obtain the coordinate data of lower extremities and trunk during gait. The coordinate data obtained were processed using the software. Walking speed, stride length, stride time and cadence were calculated as spatiotemporal variables of walking. Forward trunk tilt angle (FTT), hip flexion and extension, and knee flexion and extension were measured as peak angles during one-gait cycle. Participants were categorized into five groups according to age by five years. Multivariate analysis of variance was performed to compare the spatiotemporal and kinematical data among groups.
Results: Significant differences among age groups were noted in terms of the walking speed and stride length. Significant differences were also observed in the FTT and hip extension angle.
Conclusions: Increased gait changes, increased peak FTT and decreased peak hip extension angle were observed with an increase of age. These altered symptoms may contribute to the screening of older adults at risk of declined physical function at an early stage.
{"title":"Effects of age and gender on spatiotemporal and kinematic gait parameters in older adults.","authors":"Ryo Tanaka, Hungu Jung, Shunsuke Yamashina, Y U Inoue, Rinna Nakamura, Haruki Toda, Takeshi Imura, Hiroyuki Tamura","doi":"","DOIUrl":"","url":null,"abstract":"<p><strong>Purpose: </strong>Gait changes are more prominently observed in older adults than in young adults, especially in kinematics of lower extremities and trunk. These changes can result in incidental falls during gait, possibly leading to inability to perform activities of daily living independently. This study aimed to investigate the effect of gender and age on gait changes, such as spatiotemporal parameters and peak joint angles in lower extremities and trunk during gait.</p><p><strong>Methods: </strong>A total of 387 participants (223 women) were included. The Microsoft Kinect V2 sensor was used to obtain the coordinate data of lower extremities and trunk during gait. The coordinate data obtained were processed using the software. Walking speed, stride length, stride time and cadence were calculated as spatiotemporal variables of walking. Forward trunk tilt angle (FTT), hip flexion and extension, and knee flexion and extension were measured as peak angles during one-gait cycle. Participants were categorized into five groups according to age by five years. Multivariate analysis of variance was performed to compare the spatiotemporal and kinematical data among groups.</p><p><strong>Results: </strong>Significant differences among age groups were noted in terms of the walking speed and stride length. Significant differences were also observed in the FTT and hip extension angle.</p><p><strong>Conclusions: </strong>Increased gait changes, increased peak FTT and decreased peak hip extension angle were observed with an increase of age. These altered symptoms may contribute to the screening of older adults at risk of declined physical function at an early stage.</p>","PeriodicalId":6897,"journal":{"name":"Acta of bioengineering and biomechanics","volume":"24 4","pages":"13-19"},"PeriodicalIF":1.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9673589","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-01-01DOI: 10.37190/abb-02020-2022-01
Marta Kozuń, M. Kaczorowski, A. Hałoń
Purpose: The aims of this paper was the analysis of the mechanical properties of dissected wall of the ascending aortic aneurysm (n = 12). Methods: All aortas were collected from men (mean age: 48 ± 12 years, mean diameter of the aneurysm: 49 mm ± 4 mm). The mechanical properties were determined based on directional tensile test. The biomechanical assay was complemented by conducting histological analysis (hematoxylin and eosin, Mallory’s trichrome, Azan stain). Results: The highest values (median) of failure Cauchy stress, failure force, Young’s modulus and stiffness coefficient were obtained for the adventitia (max = 1.40 MPa, Fmax = 4.05 N, E = 26.11 MPa, k = 1.06 N/mm). Conclusions: The results indicate that the mechanical function of the adventitia in healthy tissue and dissected ascending aorta aneurysm is the same, i.e., it protects the vessel against destruction. The failure Cauchy stresses found in the media and intima are comparable and amounted to 0.23 and 0.21 MPa, respectively. The results indicate that dissection affects the mechanical properties of ascending aorta wall layers. The mechanical loads are probably transferred within the dissected aneurysmal wall not only through the media, but also through the intima.
目的:对12例升主动脉瘤夹层壁的力学特性进行分析。方法:所有动脉瘤均为男性，平均年龄48±12岁，动脉瘤平均直径49 mm±4 mm。通过定向拉伸试验确定了材料的力学性能。生物力学试验辅以组织学分析(苏木精和伊红，Mallory’s三色，Azan染色)。结果:外膜的破坏柯西应力、破坏力、杨氏模量和刚度系数的最大值(中位数)为:max = 1.40 MPa, Fmax = 4.05 N, E = 26.11 MPa, k = 1.06 N/mm。结论:健康组织外膜与剥离的升主动脉动脉瘤具有相同的机械功能，即保护血管不受破坏。在中膜和内膜中发现的失败柯西应力具有可比性，分别为0.23和0.21 MPa。结果表明，夹层影响升主动脉壁层的力学性能。机械载荷可能不仅通过中膜，而且通过内膜在夹层内传递。
{"title":"The layer-specific biomechanical properties of dissecting ascending aortic aneurysm (Stanford type A of dissection)","authors":"Marta Kozuń, M. Kaczorowski, A. Hałoń","doi":"10.37190/abb-02020-2022-01","DOIUrl":"https://doi.org/10.37190/abb-02020-2022-01","url":null,"abstract":"Purpose: The aims of this paper was the analysis of the mechanical properties of dissected wall of the ascending aortic aneurysm (n = 12). Methods: All aortas were collected from men (mean age: 48 ± 12 years, mean diameter of the aneurysm: 49 mm ± 4 mm). The mechanical properties were determined based on directional tensile test. The biomechanical assay was complemented by conducting histological analysis (hematoxylin and eosin, Mallory’s trichrome, Azan stain). Results: The highest values (median) of failure Cauchy stress, failure force, Young’s modulus and stiffness coefficient were obtained for the adventitia (max = 1.40 MPa, Fmax = 4.05 N, E = 26.11 MPa, k = 1.06 N/mm). Conclusions: The results indicate that the mechanical function of the adventitia in healthy tissue and dissected ascending aorta aneurysm is the same, i.e., it protects the vessel against destruction. The failure Cauchy stresses found in the media and intima are comparable and amounted to 0.23 and 0.21 MPa, respectively. The results indicate that dissection affects the mechanical properties of ascending aorta wall layers. The mechanical loads are probably transferred within the dissected aneurysmal wall not only through the media, but also through the intima.","PeriodicalId":6897,"journal":{"name":"Acta of bioengineering and biomechanics","volume":"1 1","pages":""},"PeriodicalIF":1.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69999523","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Q I Wang, Hong Yuan, Mingming Guo, Lingzhi Meng, Zuoyao Long, Y U Long, Huifeng Yang
Purpose: A three-dimensional finite element model of the lower cervical spine was established to evaluate the biomechanical stability and stress distribution of the new lower cervical interzygapophyseal fusion device (IZFD) developed by ourselves under different construct. The aim of this study was to provide theoretical basis for further clinical application.
Methods: A normal fresh cadaveric specimen (male, 35 years old) was used to establish an intact three-dimensional finite element model of C3-C6. On this basis, the comparative finite element models of the lateral mass screw rod (LMSR) system and LMSR+IZFD were established. Only C4-C5 is fixed in the lateral mass. The range of motion (ROM) and stress distribution in the flexion,extension, lateral bending and rotation of the C4-C5 segment under the three constructs were analyzed.
Results: The ROM and stress distribution of the three-dimensional finite element model under load construct were within a reasonable range, which proved the validity and reliability of the model. The ROM and stress distribution of C4-C5 segment was significantly decreased in both LMSR and LMSR+IZFD constructs than those in the intact construct. The ROM and stresss distribution were even smaller in LMSR+IZFD construct than in LMSR construct.
Conclusions: The IZFD combined with LMSR system can provide satisfactory stability for the lower cervical spine, and the IZFD can further improve the fixation effect of the LMSR system.
{"title":"Three-dimensional finite element analysis of a novel interzygapophyseal fusion device for lower cervical spine.","authors":"Q I Wang, Hong Yuan, Mingming Guo, Lingzhi Meng, Zuoyao Long, Y U Long, Huifeng Yang","doi":"","DOIUrl":"","url":null,"abstract":"<p><strong>Purpose: </strong>A three-dimensional finite element model of the lower cervical spine was established to evaluate the biomechanical stability and stress distribution of the new lower cervical interzygapophyseal fusion device (IZFD) developed by ourselves under different construct. The aim of this study was to provide theoretical basis for further clinical application.</p><p><strong>Methods: </strong>A normal fresh cadaveric specimen (male, 35 years old) was used to establish an intact three-dimensional finite element model of C3-C6. On this basis, the comparative finite element models of the lateral mass screw rod (LMSR) system and LMSR+IZFD were established. Only C4-C5 is fixed in the lateral mass. The range of motion (ROM) and stress distribution in the flexion,extension, lateral bending and rotation of the C4-C5 segment under the three constructs were analyzed.</p><p><strong>Results: </strong>The ROM and stress distribution of the three-dimensional finite element model under load construct were within a reasonable range, which proved the validity and reliability of the model. The ROM and stress distribution of C4-C5 segment was significantly decreased in both LMSR and LMSR+IZFD constructs than those in the intact construct. The ROM and stresss distribution were even smaller in LMSR+IZFD construct than in LMSR construct.</p><p><strong>Conclusions: </strong>The IZFD combined with LMSR system can provide satisfactory stability for the lower cervical spine, and the IZFD can further improve the fixation effect of the LMSR system.</p>","PeriodicalId":6897,"journal":{"name":"Acta of bioengineering and biomechanics","volume":"24 2","pages":"187-193"},"PeriodicalIF":1.0,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139680463","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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