Medical Engineering & Physics最新文献

{"title":"Mechanisms of cutting soft tissues using snare-type tools","authors":"Jinghang Wang,&nbsp;Urara Satake,&nbsp;Toshiyuki Enomoto","doi":"10.1016/j.medengphy.2025.104314","DOIUrl":"10.1016/j.medengphy.2025.104314","url":null,"abstract":"<div><div>Cold snare polypectomy (CSP) is the predominant method for removing colonic polyps under 6 mm, utilizing snare-type tools as cutting tools. However, complete resection rates often decrease due to occasional cutting failure. Understanding the cutting mechanisms of snare-type tools is thus crucial for optimizing both the tool and procedure. Research on CSP has primarily focused on surgical case studies, with limited focus on the snare tools. This study investigates the cutting mechanisms of snare-type tools, examining the effects of cutting speed and snare properties on cutting force. The results show that the internal tissue fractures first during CSP, followed by the external tissue. High cutting speeds and thin wire ropes reduce the cutting force required and produce flatter cut cross-sections. Cold snare defect protrusions are primarily due to the high toughness and strength of the submucosa layer tissue, which impedes internal tissue fracture. These findings enhance the understanding of the internal fracture mechanism of soft tissue and provide valuable insights for optimizing snare-type tools, potentially improving the efficacy and safety of polyp resection procedures.</div></div>","PeriodicalId":49836,"journal":{"name":"Medical Engineering & Physics","volume":"138 ","pages":"Article 104314"},"PeriodicalIF":1.7,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143548605","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":"Effect of uncertainties in musculoskeletal modeling inputs on sensitivity of knee joint finite element simulations","authors":"Sana Jahangir ,&nbsp;Will Bosch ,&nbsp;Amir Esrafilian ,&nbsp;Mika E. Mononen ,&nbsp;Petri Tanska ,&nbsp;Lauri Stenroth ,&nbsp;Marius Henriksen ,&nbsp;Tine Alkjær ,&nbsp;Rami K. Korhonen","doi":"10.1016/j.medengphy.2025.104313","DOIUrl":"10.1016/j.medengphy.2025.104313","url":null,"abstract":"<div><div>Musculoskeletal finite element modeling is used to estimate mechanical responses of knee joint tissues but involves uncertainties in muscle activations, marker locations, cartilage stiffness, maximum isometric forces, and gait parameter personalization. This study investigates how these uncertainties affect cartilage mechanical responses in knee joint finite element models during walking. We selected three subjects and constructed five musculoskeletal models for each, representing different variations of modeling assumptions, along with a reference model using conventional assumptions. We then ran finite element simulations of knee joints using both personalized gait inputs (motion and loading boundary conditions) and non-personalized gait inputs from literature. Our results demonstrated that varying modeling assumptions, such as optimization function for muscle activation patterns, knee marker position, knee cartilage stiffness, and maximum isometric force, produced highly subject-specific effects. Differences between the reference and altered models ranged from 3% to 30% in musculoskeletal modeling and from 1% to 61% in finite element modeling results. The largest effects occurred with non-personalized gait data, resulting in up to 6- and 2-fold changes in musculoskeletal and finite element modeling results, respectively. This study highlights the sensitivity of knee mechanics to different modeling assumptions and underscores the importance of applying personalized gait parameters for accurate finite element simulations.</div></div>","PeriodicalId":49836,"journal":{"name":"Medical Engineering & Physics","volume":"138 ","pages":"Article 104313"},"PeriodicalIF":1.7,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143679295","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":"Fatigue test evaluation of a customised humeral component for an instrumented total elbow prosthesis and strain validation study","authors":"Marim Basiouny ,&nbsp;Simon Lambert ,&nbsp;Chin Kuenfoo ,&nbsp;Stephen Taylor","doi":"10.1016/j.medengphy.2025.104311","DOIUrl":"10.1016/j.medengphy.2025.104311","url":null,"abstract":"<div><div>The survival rate of total elbow arthroplasty (TEA) is negatively impacted by the lack of available data on elbow biomechanics. This study developed a modified humeral component for TEA that is purposed to be instrumented to generate real-time 6 degrees of freedom (d.o.f) force and moment data during activities of daily living (ADL). The objectives are twofold: (1) to assess the safety of the modified humeral component under peak anticipated loads in fatigue, and (2) verify the strains measured under physiological loads with strains modelled using finite element analysis (FEA). Four modified titanium alloy humeral components were welded, and fatigue tested at 5 Hz for 5 million cycles under a compressive load of 700 N corresponding to moderate ADL. The strains were measured using triaxial 350 Ω rectangular rosette (45°) strain gauges bonded to three specific locations on the humeral component confirmed through an FE study. The four welded humeral components successfully withstood fatigue conditions and did not deform. The measured and modelled principal strains were confirmed to be highest at the external wall of the lateral cavity, with a percentage difference of &lt;10 %.</div></div>","PeriodicalId":49836,"journal":{"name":"Medical Engineering & Physics","volume":"138 ","pages":"Article 104311"},"PeriodicalIF":1.7,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143511819","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":"Mechanical properties of decellularized porcine esophagus: Preliminary results","authors":"Romane LESIEUR ,&nbsp;Agnès DROCHON ,&nbsp;Marlène DURAND","doi":"10.1016/j.medengphy.2025.104294","DOIUrl":"10.1016/j.medengphy.2025.104294","url":null,"abstract":"<div><div>Esophageal tissue engineering is a promising approach to create an esophageal substitute after surgical resection of a part of the organ. Regeneration of esophageal tissue may be achieved using some synthetic or biological scaffolds. In the present study, scaffolds are obtained through the decellularization of porcine esophagi. In view of future implantation, it is important to test the mechanical properties of the decellularized matrices and to compare them with the data obtained for native pig esophagi. Results of longitudinal and circumferential traction experiments as well as inflation and burst tests are presented. The results obtained for the compliance of porcine decellularized matrices are novel. It is concluded that the decellularized matrices are suitable for use as esophageal substitutes.</div></div>","PeriodicalId":49836,"journal":{"name":"Medical Engineering & Physics","volume":"137 ","pages":"Article 104294"},"PeriodicalIF":1.7,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143444393","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 FE model investigating the bone-implant interface of Osseointegrated prosthetics to better understand how forces are transferred under loading","authors":"Tiereny McGuire ,&nbsp;Arul Ramasamy ,&nbsp;Anthony M J Bull","doi":"10.1016/j.medengphy.2025.104304","DOIUrl":"10.1016/j.medengphy.2025.104304","url":null,"abstract":"<div><h3>Background</h3><div>Osseointegrated prostheses (OIP) use is increasing for above-knee amputees who have difficulties with sockets. This study aims to simulate the bone-implant interface under loading using a 3D finite element (FE) model and quantify force distribution to produce hypotheses on bone remodelling and implant failure, informing implant and surgical design, and rehabilitation protocols.</div></div><div><h3>Methods</h3><div>Ten customised 3D femur FE models (5 female, 5 male) were generated from CT scans and bone-implant assemblies created. The bone was subdivided into seven Gruen Zones and four proximal femur regions. Boundary conditions were taken from the literature.</div></div><div><h3>Results</h3><div>The highest stresses were found in the implant (Max: 113.9 MPa), whilst highest strains were seen in the bone (Max: 4.89 %). Stress and strain were unevenly distributed, with distal regions experiencing stress shielding effects and areas around the implant tip experiencing significantly higher stresses and strains (<em>p</em> &lt; .001). Maximum stresses were higher in female bones (<em>p</em> &lt; .01), whilst shorter residuum lengths saw significantly lower stresses (<em>p</em> &lt; .05).</div></div><div><h3>Conclusion</h3><div>Sex, size and limb length are all important factors and these need to be accounted for when designing and implanting OIPs.</div></div>","PeriodicalId":49836,"journal":{"name":"Medical Engineering & Physics","volume":"137 ","pages":"Article 104304"},"PeriodicalIF":1.7,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143444391","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":"Atomic-level insights into the adsorption of various biopolymers on Fe3O4 nanoparticles: A molecular dynamics study","authors":"Farzad Pashmforoush,&nbsp;Shahram Ajori","doi":"10.1016/j.medengphy.2025.104301","DOIUrl":"10.1016/j.medengphy.2025.104301","url":null,"abstract":"<div><div>In this study, molecular dynamics simulations were implemented to investigate the atomic-level interactions of three different biopolymers (Gum Tragacanth, pectin, and carrageenan) on Fe₃O₄ nanoparticles. The main purpose was to achieve a deep understanding of the adsorption dynamics between these biopolymers and magnetic nanoparticle. In this respect, initially, the adsorption models were simulated under NVT conditions, and consequently, in-depth analyses of interaction energies, concentration profiles, and radial distribution functions were conducted. According to the obtained results, a strong adsorption of all three biopolymers on nanoparticles surface was observed, caused mainly by hydrogen bonds and van der Waals forces. However, Fe₃O₄/carrageenan demonstrated the strongest binding affinity among the biopolymer-nanoparticle pairs. This research provides critical atomic-level insights into biopolymer-nanoparticle interactions, bridging a significant knowledge gap and enhancing the understanding and potential application of Fe₃O₄-based materials in cutting-edge biomedical technologies.</div></div>","PeriodicalId":49836,"journal":{"name":"Medical Engineering & Physics","volume":"137 ","pages":"Article 104301"},"PeriodicalIF":1.7,"publicationDate":"2025-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143444392","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":"Assessment of pre- and post-operative gait dynamics in total knee arthroplasty by a wearable capture system","authors":"Zhuoxi Bi ,&nbsp;Wenquan Cui ,&nbsp;Luming Feng ,&nbsp;Yaxin Liu ,&nbsp;Xin Ma ,&nbsp;Shihao Li ,&nbsp;Changle Ren ,&nbsp;Liming Shu","doi":"10.1016/j.medengphy.2025.104309","DOIUrl":"10.1016/j.medengphy.2025.104309","url":null,"abstract":"<div><h3>Background</h3><div>Walking function reconstruction is suboptimal after total knee arthroplasty. However, a comprehensive investigation of kinematic and kinetic parameters before and after total knee arthroplasty is lacking. This study aimed to quantitatively compare the differences in gait parameters before and after total knee arthroplasty with those of healthy control group.</div></div><div><h3>Methods</h3><div>This study utilized a wearable capture system to obtain gait parameters from pre- operative and one-year post- operative patients, as well as from the healthy control group. The parameters included walking speed, the stance phase percentage during the gait cycle, knee flexion angle, center of pressure trajectory, vertical ground reaction force, and its moment on the coronal plane of the knee joint.</div></div><div><h3>Results</h3><div>Post-total knee arthroplasty patients presented an averaged 12.5 % improvement in walking speed and an averaged 19.75 % increasement in the maximum knee flexion angle during the gait cycle, although both were still lower than those of the healthy control group. During the stance phase, the vertical ground reaction force exhibited a less pronounced double-hump feature, and compared to preoperative levels, the peak of the coronal plane moment of the knee was reduced by approximately half.</div></div><div><h3>Conclusion</h3><div>One-year post- total knee arthroplasty patients exhibited improved walking function compared to preoperative levels, but a gap remained compared to healthy control group. Additionally, preoperative gait abnormalities persisted postoperatively.</div></div>","PeriodicalId":49836,"journal":{"name":"Medical Engineering & Physics","volume":"137 ","pages":"Article 104309"},"PeriodicalIF":1.7,"publicationDate":"2025-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143394474","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 novel 3D lightweight model for COVID-19 lung CT Lesion Segmentation","authors":"Jingdong Yang ,&nbsp;Shaoyu Huang ,&nbsp;Han Wang ,&nbsp;Yuhang Lu ,&nbsp;Wei liu ,&nbsp;Yan Shen ,&nbsp;Xiaohong Fu","doi":"10.1016/j.medengphy.2025.104297","DOIUrl":"10.1016/j.medengphy.2025.104297","url":null,"abstract":"<div><div>3D-based medical image segmentation, offering enhanced spatial information compared to 2D slice-based methods, encounters challenges arising from factors such as a restricted clinical sample size, imbalanced foreground-background pixel distribution, and suboptimal generalization performance. To address these challenges, we propose a lightweight segmentation model tailored to 3D medical images. Employing the K-means algorithm, our approach efficiently extracts the Region of Interest (ROI) from medical images, facilitating lung area segmentation while minimizing interference from background pixels. We address the risk of model overfitting by adopting the Focal loss in conjunction with the Dice coefficient as our loss function. Feature extraction capabilities are bolstered through the incorporation of a parallel attention mechanism at skip connections, aiming to enhance the representation of both shallow and deep layers. Moreover, we optimize computational efficiency and memory utilization by substituting 3 × 3 convolutions with depth-wise separable convolutions and integrating residual connections for improved gradient propagation. The introduction of Ghost-inspired 1 × 1 convolution ensures consistent feature dimensions before and after residual connections. Experimental evaluation, conducted on a dataset comprising 199 COVID-19-Seg cases through 5-fold cross-validation, underscores the superior performance of our proposed model. Evaluation metrics, including Average Surface Distance (ASD), accuracy, sensitivity, Dice coefficient, and Intersection over Union (IOU) accuracy, yield values of 19.880, 99.90 %, 58.90 %, 56.10 %, and 41.00 %, respectively. In comparison to the other state-of-the-art segmentation models, our approach achieves heightened segmentation accuracy and generalization performance while incurring only a marginal increase in parameters and computational complexity.</div></div>","PeriodicalId":49836,"journal":{"name":"Medical Engineering & Physics","volume":"137 ","pages":"Article 104297"},"PeriodicalIF":1.7,"publicationDate":"2025-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143402751","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 patient-matched prosthesis for thumb amputations: Design, mechanical and functional evaluation","authors":"Federico Stacchiotti ,&nbsp;Chiara Bregoli ,&nbsp;Rubens Ferrari ,&nbsp;Jacopo Fiocchi ,&nbsp;Kavin Morellato ,&nbsp;Carlo Alberto Biffi ,&nbsp;Mattia Frascio ,&nbsp;Matilde Minuto ,&nbsp;Ausonio Tuissi ,&nbsp;Emanuele Gruppioni","doi":"10.1016/j.medengphy.2025.104296","DOIUrl":"10.1016/j.medengphy.2025.104296","url":null,"abstract":"<div><div>Thumb amputations strongly affect hand functionality in daily activities. The currently available solutions, such as microsurgical treatments and external vacuum prostheses present disadvantages, which can be successfully addressed through the osseointegration technique. However, despite its widespread use in oral applications, only a few osseointegrated solutions for the treatment of hand-finger amputations are available. Bone remaining limbs may have different lengths, diameters, and conditions and no patient-matched osseointegrated medical devices are available on the market. The manuscript presents the first patient-matched medical device for the treatment of thumb amputations. The prosthesis mainly consists of three components: an osseointegrated fixture which is implanted into the medullary canal of the bone remaining limb, an abutment, and an external digital prosthesis. The design phase is followed by computational and experimental analysis to optimize the design of each component attached to the osseointegrated fixture in order to preserve the implant fixture and bone. The maximum force generated during the pinch test in a healthy subject is approximately 80 N. The mechanical performance required during daily activities is achieved by the novel proposed device and the obtained results confirm that, in case of loads greater than daily ones, the failure may occur in the abutment component which is external to the body. A limitation of the current study consists in the lack of analysis on the bone-implant interface for which specific investigations would be required: currently, the contact between bone and fixture is assumed to be fixed, i.e. no micro motions are considered. Research is ongoing to test the entire device in a clinical study to collect quantitative and qualitative information from patients and surgeons.</div></div>","PeriodicalId":49836,"journal":{"name":"Medical Engineering & Physics","volume":"137 ","pages":"Article 104296"},"PeriodicalIF":1.7,"publicationDate":"2025-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143386771","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":"Influence of surface type on outdoor gait parameters measured using an In-Shoe Motion Sensor System","authors":"Hiroki Shimizu ,&nbsp;Kyoma Tanigawa ,&nbsp;Anuradhi Bandara ,&nbsp;Shinichi Kawamoto ,&nbsp;Shota Suzuki ,&nbsp;Momoko Nagai-Tanima ,&nbsp;Tomoki Aoyama","doi":"10.1016/j.medengphy.2025.104295","DOIUrl":"10.1016/j.medengphy.2025.104295","url":null,"abstract":"<div><div>The objectives of this study were to measure outdoor gait parameters using an In-Shoe Motion Sensor System (IMS) and evaluate how different types of surfaces affect various gait dynamics. Accurate outdoor gait data are crucial for effective fall risk assessment because surface irregularities and tripping hazards often result in falls during walking. An IMS was used in this study to collect spatiotemporal, spatial, and foot parameters from 27 healthy adults walking on indoor asphalt, soil, and grass surfaces. Data were recorded during a 6-minute walk test, with measurements taken every 2 min and analyzed using the Statistical Package for the Social Sciences. The results showed significant differences in foot clearance, heel height, and gait cycle across surfaces. Walking on grass significantly increased foot height, swing time, and roll angle of heel contact. These findings may help develop interventions to prevent falls.</div></div>","PeriodicalId":49836,"journal":{"name":"Medical Engineering & Physics","volume":"137 ","pages":"Article 104295"},"PeriodicalIF":1.7,"publicationDate":"2025-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143394473","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}