Medical Engineering & Physics最新文献

{"title":"Effect of plantar fascia stiffness on plantar windlass mechanism and arch: Finite element method and dual fluoroscopic imaging system verification","authors":"Qiaolin Zhang ,&nbsp;Dong Sun ,&nbsp;Meizi Wang ,&nbsp;Viktória Tafferner-Gulyás ,&nbsp;Hairong Chen ,&nbsp;István Bíró ,&nbsp;Yaodong Gu","doi":"10.1016/j.medengphy.2024.104259","DOIUrl":"10.1016/j.medengphy.2024.104259","url":null,"abstract":"<div><div>This study explored the relationship between the foot arch stiffness and windlass mechanism, focusing on the contribution of the posterior transverse arch. Understanding the changing characteristics of foot stiffness is critical for providing a scientific basis for treating foot-related diseases. Based on a healthy male's computed tomography, kinematic, and dynamics data, a foot musculoskeletal finite element model with a dorsiflexion angle of 30°of metatarsophalangeal joint was established. Analyze the changes in stress distribution of the plantar fascia, metatarsophalangeal joint angle, arch height, and length during barefoot walking as the stiffness of the plantar fascia varies from 25 % to 200 %. For validation, the simulated arch parameters were compared with the dual fluorescence imaging system measurements. The width of transverse arch, height, and length of longitudinal arch measured by the dual fluorescence imaging system were 45.14 ± 1.63 mm, 29.29 ± 1.57 mm, and 155.16 ± 2.69 mm, respectively. The results of the simulation were 46.51 mm, 29.96 mm, and 156.71 mm, respectively. With the increase of plantar fascia stiffness, the effect of the windlass mechanism increased, the flexion angle of the metatarsophalangeal joint decreased, the distal stress of plantar fascia decreased gradually, while the proximal and middle stress increased, the transverse arch angle increased, but when the plantar fascia stiffness exceeds 150 %, the transverse arch angle decreases. The increase of plantar fascia stiffness will increase the effect of the windlass mechanism but decrease the flexion angle of the metatarsophalangeal joint. The stiffness of the plantar fascia influences the behavior of the plantar fascia. The plantar fascia stiffness affects the distal tension of the plantar fascia by affecting the flexion of the metatarsophalangeal joint in the plantar windlass mechanism. It affects the stiffness of the transverse arch of the foot together with the ground reaction force acting on the distal metatarsal.</div></div>","PeriodicalId":49836,"journal":{"name":"Medical Engineering & Physics","volume":"134 ","pages":"Article 104259"},"PeriodicalIF":1.7,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142698491","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}

{"title":"The effect of the length of chimney's protrusion on the hemodynamics of abdominal aorta stent graft after endovascular aneurysm repair","authors":"Moshe Brand ,&nbsp;Hila Ben-Gur ,&nbsp;Moshe Halak","doi":"10.1016/j.medengphy.2024.104256","DOIUrl":"10.1016/j.medengphy.2024.104256","url":null,"abstract":"<div><h3>Introduction</h3><div>Abdominal aortic aneurysms present a significant clinical challenge, particularly when located near the renal arteries. In cases of infra-renal abdominal aortic aneurysms, the main stent graft may occlude the renal arteries, disrupting blood supply. To prevent this, two 'chimney' stent grafts can be implanted to maintain renal artery perfusion.</div></div><div><h3>Method</h3><div>This study investigates the impact of chimney stent graft protrusion length on the hemodynamics of stent graft using computational fluid dynamics (CFD). Two chimney configurations were analyzed, with the chimney protruding 10 and 30 mm above the upper part of the main stent graft. Key hemodynamic parameters were compared, including wall shear stress, blood flow velocity, and pathlines.</div></div><div><h3>Results</h3><div>The CFD analysis showed no substantial differences in hemodynamic parameters between these configurations.</div></div><div><h3>Conclusions</h3><div>The findings indicate negligible hemodynamic differences between the two chimney configurations. A chimney that protrudes 30 mm above the main stent graft is a viable option and may help reduce procedure time and patient risk.</div></div>","PeriodicalId":49836,"journal":{"name":"Medical Engineering & Physics","volume":"134 ","pages":"Article 104256"},"PeriodicalIF":1.7,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142697999","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}

{"title":"Open laminectomy plus posterolateral fusion versus open laminectomy plus transforaminal lumbar interbody fusion surgical approaches for fusing degenerated L4-L5 segment: A comparative finite element study","authors":"Kishore Pradeep,&nbsp;Bidyut Pal","doi":"10.1016/j.medengphy.2024.104261","DOIUrl":"10.1016/j.medengphy.2024.104261","url":null,"abstract":"<div><div>Various finite element (FE) studies reported the biomechanical effects of fusion surgeries in the lumbar spine. However, a comparative study on Open laminectomy plus Posterolateral Fusion (OL-PLF) and Open Laminectomy plus Transforaminal Lumbar Interbody Fusion (OL-TLIF) for fusing an L4-L5 segment has not been reported in the literature. The present comparative FE study evaluates the biomechanical variations in an L4-L5 segment fused using OL-PLF and OL-TLIF surgical approaches. The three-dimensional implanted models were constructed from a computed-tomography scan dataset using image processing software. The models were simulated for the physiological movements such as lateral bending, flexion and extension. The OL-TLIF model had a considerably larger peak equivalent strain than the OL-PLF model under extension (126 %), lateral bending (88 %) and flexion (13 %). However, in both implanted models, a peak equivalent strain above the compressive yield strain limit of the vertebra (0.007) was observed over 60 % of the L4-L5 fused segment, indicating an imminent post-operative bone failure under the imposed loading conditions. The maximum equivalent strain observed in the disc and endplates of the L3-L4 segment was substantially larger to initiate the adjacent segment degeneration. No discernible biomechanical benefits were observed for the OL-TLIF or OL-PLF approaches in fusing the L4-L5 segment.</div></div>","PeriodicalId":49836,"journal":{"name":"Medical Engineering & Physics","volume":"134 ","pages":"Article 104261"},"PeriodicalIF":1.7,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142697998","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}

{"title":"An in vitro experimental study on the synergistic pathogenicity analysis of pulsatile tinnitus involving venous flow velocity, sigmoid sinus wall dehiscence and sinus malformation","authors":"Shan Tian ,&nbsp;Lanyue Chen ,&nbsp;Chao Huang ,&nbsp;Zhaohui Liu ,&nbsp;Lizhen Wang ,&nbsp;Yubo Fan","doi":"10.1016/j.medengphy.2024.104257","DOIUrl":"10.1016/j.medengphy.2024.104257","url":null,"abstract":"<div><div>Pulsatile tinnitus (PT) is synchronous with patients’ heartbeat, with various reported intracranial etiologies. Sigmoid sinus wall dehiscence (SSWD), sinus malformation and high venous flow velocity were common marks of PT and were generally treated as independent etiology in clinic, but their coupling effect remains unclear. This study aimed to investigate the synergistic pathogenicity of these etiologies. The generation and propagation of venous sound was simulated by in vitro experiment. The entity models of sinus vessel, sinus wall and temporal bone cavity were 3D-printed using resin based on CT imaging. Pulsatile venous flow was generated through sinus lumen, with five velocity levels. Venous sound was collected and analyzed. It was found that pressure and pulsation of venous sound were determined by the coupling of three etiology conditions. Low velocity would not induce pulsatile sound anyway. Sub-high or higher velocity induced mild pulsatile sound coupling with normal sinus and wall. Medium or higher velocity induced moderate pulsatile sound coupling with SSWD and normal sinus. Sub-low or higher velocity induced moderate or severe pulsatile sound coupling with SSWD and sinus malformation. In conclusion, PT diagnosis should include the three investigated etiologies due to their contribution to amplifying venous sound. Among the three etiologies, SSWD exhibits the highest pathogenicity, while high venous flow velocity may reduce the effectiveness of SS wall reconstruction, and sinus malformation may exacerbate the intensity of tinnitus induced by SSWD.</div></div>","PeriodicalId":49836,"journal":{"name":"Medical Engineering & Physics","volume":"134 ","pages":"Article 104257"},"PeriodicalIF":1.7,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142698492","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}

{"title":"Cadaveric validation of markerless tracking using weightbearing computed tomography versus conventional computed tomography imaging techniques","authors":"Katee N. Perez ,&nbsp;Andrew C. Peterson ,&nbsp;Rich J. Lisonbee ,&nbsp;J.Peter Loan ,&nbsp;Amy L. Lenz","doi":"10.1016/j.medengphy.2024.104252","DOIUrl":"10.1016/j.medengphy.2024.104252","url":null,"abstract":"<div><div>This study aimed to validate the use of weightbearing computed tomography against conventional computed tomography and against bead tracking for markerless tracking of key foot and ankle bones. A left cadaveric limb was implanted with tantalum beads and underwent conventional computed tomography and weightbearing computed tomography scanning, followed by biplane fluoroscopy motion capture to simulate gait. Bone models from conventional computed tomography and weightbearing computed tomography were compared for surface differences and kinematic analysis across six joints. Results showed the average surface distance difference across all weightbearing computed tomography bones were a fraction of a voxel smaller than the conventional computed tomography bones on average. Additionally, the absolute mean and standard deviation of the mean angle differences across all trials, joints, and planes was less than one degree. Weightbearing computed tomography demonstrated comparable accuracy to conventional computed tomography and to bead tracking, confirming its utility in dynamic biomechanical analysis with reduced radiation exposure and the ability to image under load. This validation supports weightbearing computed tomography's broader adoption in clinical and research settings for enhanced foot and ankle diagnostics and treatment.</div></div>","PeriodicalId":49836,"journal":{"name":"Medical Engineering & Physics","volume":"134 ","pages":"Article 104252"},"PeriodicalIF":1.7,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142698493","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}

{"title":"A compact and cost-effective gait simulator to advance prosthesis development with reduced reliance on human subject testing: Development, validation and application","authors":"S. Sudeesh,&nbsp;M.S. Shunmugam,&nbsp;S. Sujatha","doi":"10.1016/j.medengphy.2024.104254","DOIUrl":"10.1016/j.medengphy.2024.104254","url":null,"abstract":"<div><div>Gait simulators play a crucial role in assessing the performance of physical prototypes of prosthetic knees, validating numerical simulation findings, and reducing dependency on user trials during prosthesis development. However, their practical application is limited because of substantial capital investment required for sophisticated high degrees-of-freedom (DOF) system development on one side and insufficient DOF for accurate simulation on the other. In this study, we evaluated the minimum DOF of thigh segment that a gait simulator should have to test the performance of prosthetic knees in a cost-effective manner. Initially, numerical simulations of swing phase of prosthetic leg with IITM polycentric knee (IPK) using 3D gait data and with different arrested DOF of the thigh were performed to identify the essential DOF of gait simulator. By comparing different cases of arrested DOF with the six-DOF ideal case, it was revealed that only sagittal plane movements, namely flexion-extension, vertical translation, and horizontal translation, are sufficient to test prosthetic knees. Subsequently, a compact and modular gait simulator was developed. Hardware-in-loop simulations of the IPK using the gait simulator were used to demonstrate its effectiveness in assessing the performance of prosthetic knees, which validated the ability of the IPK to extend completely without an extension assist before heel contact. Additionally, it was exposed that the IPK's extension stop needs redesigning to effectively absorb the impact energy when the knee extends completely before heel contact. These findings emphasize the significance of a cost-effective gait simulator in prosthesis development and reduce dependency on user trials.</div></div>","PeriodicalId":49836,"journal":{"name":"Medical Engineering & Physics","volume":"134 ","pages":"Article 104254"},"PeriodicalIF":1.7,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142654612","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}

{"title":"3D bioheat transfer mapping reveals nanomagnetic particles effectiveness in radiofrequency hyperthermia breast cancer treatment comparing to experimental study","authors":"Mahsa Kavousi ,&nbsp;Erfan Saadatmand ,&nbsp;Mahboubeh Masoumbeigi ,&nbsp;Rabi Mahdavi ,&nbsp;Nader Riyahi Alam","doi":"10.1016/j.medengphy.2024.104249","DOIUrl":"10.1016/j.medengphy.2024.104249","url":null,"abstract":"<div><div>Radiofrequency (RF) hyperthermia has been widely used for tumor ablation since magnetic-fluid-hyperthermia (MFH) can be utilized for increasing temperature in tumor-region as a complementary-method for hyperthermia. In this study, the effectiveness of using the magnetite-nanoparticles (Fe₃O₄) in RF hyperthermia for breast cancer (BC) treatment by determining 3D-temperature-distribution using bioheat-transfer-mapping was evaluated. A breast-phantom with a tumor region was placed in an RF-device with 13.56 MHz frequency in different states (with and without-nanomagnetite). Parallelly, the calculations of the RF-wave and bioheat-equation were accomplished by numerical-simulation and finite-element-method (FEM) in COMSOL-software. The temperature differences were experimentally measured at different points of the phantom with a precision of 0.1 °C, with temperature of 3.6 °C and 6.1 °C in without and with nanomagnetic conditions in tumor area, respectively, and also for normal area with temperature of 1.8 °C and 1.9 °C in non-presence and presence states of 0.05 gr magnetite for both conditions, respectively. Moreover, the difference between the simulation and the experimental results was 0.54–1.1 %. The conformity between temperature measurement in experimental and simulation studies in tumor and normal areas showed the effectiveness of the application of MNPs for RF hyperthermia in tissue equivalent breast phantom. Finally, the positive effect of 0.05 gr of MNPs on BC treatment was confirmed.</div></div>","PeriodicalId":49836,"journal":{"name":"Medical Engineering & Physics","volume":"133 ","pages":"Article 104249"},"PeriodicalIF":1.7,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142571570","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}

{"title":"Monitoring focused ultrasound ablation surgery (FUAS) using echo amplitudes of the therapeutic focused transducer","authors":"Yufeng Zhou ,&nbsp;Xiaobo Gong ,&nbsp;Yaqin You","doi":"10.1016/j.medengphy.2024.104247","DOIUrl":"10.1016/j.medengphy.2024.104247","url":null,"abstract":"<div><h3>Objective</h3><div>B-mode sonography is commonly used to monitor focused ultrasound ablation surgery (FUAS), but has limitations in sensitivity. More accurate and reliable prediction of coagulation is required.</div></div><div><h3>Methods</h3><div>The focused ultrasound (FUS) transducer was adapted for echo reception. Numerical simulations compared the normalized echo amplitudes from the FUS transducer and imaging probe at varying tissue depths and frequencies with a 3 mm necrosis at focus. An <em>ex vivo</em> experiment then evaluated echo changes from the FUS transducer and ultrasound imaging probe under different settings. Finally, coagulation prediction using FUS echo data was compared to sonography in a clinical <em>ex vivo</em> context.</div></div><div><h3>Results</h3><div>The echo amplitudes from the FUS transducer exhibit a less pronounced decline with increasing tissue penetration depth compared to the ultrasound imaging probe. In <em>ex vivo</em> bovine liver experiments at depths of 2 cm and 4 cm, the FUS transducer detected normalized echo amplitudes that were significantly larger (i.e., 2∼3 folds) than those received by the ultrasound imaging probe. Moreover, multi-layered <em>ex vivo</em> tissue experiments that replicate clinical conditions revealed that coagulation prediction utilizing the FUS transducer's echo amplitudes achieved superior accuracy (91.2% vs. 60.3 %), sensitivity (92.1% vs. 54.5 %), and negative prediction (78.9% vs. 30.6 %), but similar specificity (88.2% vs. 84.6 %) and positive prediction (95.9% vs. 93.8 %) in comparison to sonography.</div></div><div><h3>Conclusion</h3><div>The echo amplitude of the FUS transducer serves as a sensitive and dependable metric for monitoring the FUAS outcomes. Its utilization may augment the procedure's safety and efficacy.</div></div>","PeriodicalId":49836,"journal":{"name":"Medical Engineering & Physics","volume":"133 ","pages":"Article 104247"},"PeriodicalIF":1.7,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142553681","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}

{"title":"Evaluation of a finite state machine algorithm to measure stepping with ankle accelerometry: Performance across a range of gait speeds, tasks, and individual walking ability","authors":"Benjamin F Cornish ,&nbsp;Karen Van Ooteghem ,&nbsp;Matthew Wong ,&nbsp;Kyle S Weber ,&nbsp;Frederico Pieruccini-Faria ,&nbsp;Manuel Montero-Odasso ,&nbsp;William E McIlroy","doi":"10.1016/j.medengphy.2024.104251","DOIUrl":"10.1016/j.medengphy.2024.104251","url":null,"abstract":"<div><div>Wearable sensors, including accelerometers, are a widely accepted tool to assess gait in clinical and free-living environments. Methods to identify phases and subphases of the gait cycle are necessary for comprehensive assessment of pathological gait. The current study evaluated the accuracy of a finite state machine (FSM) algorithm to detect strides by identifying gait cycle subphases from ankle-worn accelerometry. Algorithm performance was challenged across a range of speeds (0.4-2.6 m/s), task conditions (e.g., single- and dual-task walking), and individual characteristics. Specifically, the study included a range of treadmill speeds in young adults and overground walking conditions in older adults with neurological disease. Manually counted and algorithm-derived stride detection from acceleration data were evaluated using error analysis and Bland-Altman plots for visualization. Overall, the algorithm successfully detected strides (&gt;96 % accuracy) across gait speed ranges and tasks, for young and older adults. The accuracy of an FSM algorithm combined with ankle-worn accelerometers, provides an analytical approach with affordable and portable tools that permits comprehensive assessment of gait unbounded by setting and proves to perform well in in walking tasks characterized by variable walking. These algorithm capabilities and advancements are critical for identifying phase dependent gait impairments in clinical and free-living assessment.</div></div>","PeriodicalId":49836,"journal":{"name":"Medical Engineering & Physics","volume":"133 ","pages":"Article 104251"},"PeriodicalIF":1.7,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142657587","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Understanding vibration exposure in wheelchair users: Experimental insights","authors":"Delphine Chadefaux ,&nbsp;Ophélie Lariviere ,&nbsp;Christophe Sauret ,&nbsp;Corentin Bosio ,&nbsp;Patricia Thoreux","doi":"10.1016/j.medengphy.2024.104253","DOIUrl":"10.1016/j.medengphy.2024.104253","url":null,"abstract":"<div><div>Addressing the complexities of manual wheelchair (MWC) vibrations is crucial for the well-being of users and their integration into society. This study investigates the experimental choices influencing the assessment of vibration exposure, aiming to contribute for enhanced MWC developments and standardized design principles. By conducting a comprehensive full factorial experiment, the impact of various factors, including four MWC loads, two speeds, five floor types, and two MWC models was examined. Notably, findings highlight the predominant influence of floor type on vibration exposure, followed by speed and, to a lesser extent, MWC properties. Furthermore, the study suggests that enlisting an able-bodied participant is more representative than using a dummy when loading the MWC, providing valuable insights into the genuine MWC/user dyad response to vibrations. This research sets the stage for a more informed and standardized approach to address the vibration exposure faced by MWC users.</div></div>","PeriodicalId":49836,"journal":{"name":"Medical Engineering & Physics","volume":"133 ","pages":"Article 104253"},"PeriodicalIF":1.7,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142657588","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}