Artigos de revistas: "Soft tissue artefacts"

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Dumas, R., Y. Lafon, E. Jacquelin e L. Chèze. "Soft tissue artefacts: compensation and modelling". Computer Methods in Biomechanics and Biomedical Engineering 12, sup1 (agosto de 2009): 103–4. http://dx.doi.org/10.1080/10255840903077345.

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Chan, Janet M. "Penile shadow artefact overlapping fractures". Radiography Open 1, n.º 1 (1 de dezembro de 2014): 4. http://dx.doi.org/10.7577/radopen.1202.

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Soft tissue shadows are commonly seen on pelvic radiographs, and radiographers may overlook or are unaware that these shadows could be artefacts. In a case study, shadow of a penis superimposed with the fracture lines at pubic ramus and it was questioned whether a fracture of ramus ischio-pubis is present. Further radiographic views were performed to demonstrate the fractures without any artefact. There are other possible pelvic artefacts that may be seen and neglected on pelvic radiographs, thus it may lead to misdiagnosis of pelvic fracture. This essay should be served as a reminder for radiographers to recognize artefacts and differentiate it from pathology.

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Lazovic, D., J. Franke e C. J. Wirth. "Computerized Tomography and Magnetic Resonance Imaging in Treatment of Congenital Luxation of the Hip". HIP International 6, n.º 3 (julho de 1996): 119–23. http://dx.doi.org/10.1177/112070009600600304.

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In treatment of congenital dislocation of the hip, a main aim is to achieve concentricity of reduction. Control by plain x-ray lacks accuracy in determining anteroposterior position. Arthrography and sonography cannot be used when a spica cast is in place. After April 1988, therefore, as an alternative in 16 hips, we have used computed tomography to determine femoral head position, acetabular angle, and extent and integrity of posterior rim. However, the presence of any metallic artefacts, unossified cartilage and the general poor-quality imaging of soft tissue associated with the technique reduce its usefulness. Since January 1990, we have instead used magnetic resonance imaging to control treatment. This technique, in 34 hips, proved accurate in determinating the femoral head position. MRI also gave better images than computed tomography of osseous and cartilaginous structures of the acetabulum and the surrounding soft tissue. Spica casting does not affect the quality of imaging. The effect of metal artefacts can be minimized by using, where necessary, implants of titanium alloy.

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de Vries, W. H. K., H. E. J. Veeger, C. B. T. M. Baten e F. C. T. van der Helm. "Upper extremity Load Spectrum in daily situations: System Accuracy and Soft Tissue Artefacts". Journal of Biomechanics 40 (janeiro de 2007): S424. http://dx.doi.org/10.1016/s0021-9290(07)70419-0.

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Metcalf, C. D., C. Phillips, A. Forrester, J. Glodowski, K. Simpson, C. Everitt, A. Darekar, L. King, D. Warwick e A. S. Dickinson. "Quantifying Soft Tissue Artefacts and Imaging Variability in Motion Capture of the Fingers". Annals of Biomedical Engineering 48, n.º 5 (19 de fevereiro de 2020): 1551–61. http://dx.doi.org/10.1007/s10439-020-02476-2.

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GÜNTHER, MICHAEL, VIKTOR A. SHOLUKHA, DANNY KESSLER, VEIT WANK e REINHARD BLICKHAN. "DEALING WITH SKIN MOTION AND WOBBLING MASSES IN INVERSE DYNAMICS". Journal of Mechanics in Medicine and Biology 03, n.º 03n04 (setembro de 2003): 309–35. http://dx.doi.org/10.1142/s0219519403000831.

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Inverse dynamics is a standard analysis in biomechanics to reconstruct time histories of internal driving forces and torques from measured external forces and segmental kinematics. The main sources of inconsistency leading to analytical artefacts in this process are skin marker and soft tissue motion. These potentially artificial high frequency fluctuations in the joint torques may serve as an erroneous basis of (misleading) assumptions with respect to muscular activity. Here we suggest techniques to reduce these errors. In both parts of this study, high-speed video and force platform data were acquired. In one part, 69 sequences of human barefoot running were sampled followed by an inverse dynamic analysis of the stance leg. The time history of the hip joint torque in the sagittal plane served as a sensitive "detector" of dynamic analysis artefacts. We show that the most important error — the relative skin to bone motion especially of the knee marker — can be reduced significantly by processing kinematic data using bone rigidity (constant segment lengths) and bony contour (frontal knee edge) information. Further on, neglecting significantly initiated soft tissue dynamics in the inverse dynamic model introduces another inconsistency in the analytical process. Therefore, in a second part of this study, soft tissue kinematics from 14 jumping sequences were identified. These data provided a set of coupling parameters of wobbling masses to the bone that were ready to be implemented in the inverse dynamic model. Using realistic bone kinematics mainly avoids phase shifts in the acceleration scenario within the leg, and thus artifical hip torque fluctuations within the whole contact period. In human running, accounting for soft tissue dynamics mainly affects the calculated timing of the hip joint torque during the impact phase.

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Lu, Ming, Cheng-Chung Lin, Tung-Wu Lu, Shi-Nuan Wang e Ching-Ho Wu. "Effects of soft tissue artefacts on computed segmental and stifle kinematics in canine motion analysis". Veterinary Record 186, n.º 2 (13 de agosto de 2019): 66. http://dx.doi.org/10.1136/vr.105352.

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Skin marker-based motion analysis has been widely used to evaluate the functional performance of canine gait and posture. However, the interference of soft tissues between markers and the underlying bones (soft tissue artefacts, STAs) may lead to errors in kinematics measurements. Currently, no optimal marker attachment sites and cluster compositions are recommended for canine gait analysis. The current study aims to evaluate cluster-level STAs and the effects of cluster compositions on the computed stifle kinematics. Ten mixed-breed healthy dogs affixed with 19 retroreflective markers on the thigh and shank were enrolled. During isolated stifle passive extension, the marker trajectories were acquired with a motion capture system, and the skeletal poses were determined by integrating fluoroscopic and CT images of the bones. The cluster-level STAs were assessed, and clusters were paired to calculate the stifle kinematics. A selection of cluster compositions was useful for deriving accurate sagittal and frontal plane stifle kinematics with flexion angles below 50 per cent of the range of motion. The findings contribute to improved knowledge of canine STAs and their influence on motion measurements. The marker composition with the smallest error in describing joint kinematics is recommended for future applications and study in dogs during dynamic gait assessment.

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Omori, Naoko, Takuya Ueda e Nobuyuki Mitsukawa. "CT-guided mapping in the removal of an impalpable, radiopaque foreign body in subcutaneous tissue: a case report". Journal of Wound Care 29, n.º 7 (2 de julho de 2020): 424–26. http://dx.doi.org/10.12968/jowc.2020.29.7.424.

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Small fragments sometimes penetrate the soft tissue, and their depth and location can be difficult to determine accurately. This case study describes localisation of a thin, short wire that had penetrated the soft tissue of a 24-year-old man's back, using computed tomography (CT) with a reference grid made with an angiographic catheter. The axial non-contrast-enhanced CT scan with the grid placed over the affected body part surveyed by the CT scout view showed that the foreign body was buried in fascia 7cm from a puncture wound. Surgical removal of the foreign body was then performed without any sequelae. CT with the use of external references that do not cause metal artefacts is a simple and helpful procedure in localising radiopaque foreign bodies.

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Goodall, Alex Francis, Alex Barrett, Elspeth Whitby e Andrew Fry. "T2*-weighted MRI produces viable fetal “Black-Bone” contrast with significant benefits when compared to current sequences". British Journal of Radiology 94, n.º 1123 (1 de julho de 2021): 20200940. http://dx.doi.org/10.1259/bjr.20200940.

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Objectives: Fetal “black bone” MRI could be useful in the diagnosis of various skeletal conditions during pregnancy without exposure to ionizing radiation. Previously suggested susceptibility-weighted imaging (SWI) is not available in the suggested form on all scanners leading to long imaging times that are susceptible to motion artefacts. We aimed to assess if an optimized T2*-weighted GRE sequence can provide viable “black bone” contrast and compared it to other sequences in the literature. Methods: A retrospective study was conducted on 17 patients who underwent fetal MRI. Patients were imaged with an optimized T2*-weighted GRE sequence, as well as at least one other “black-bone” sequence. Image quality was scored by four blinded observers on a five-point scale. Results: The T2*-weighted GRE sequence offered adequate to excellent image quality in 63% of cases and scored consistently higher than the three other comparison sequences when comparing images from the same patient. Image quality was found to be dependent on gestational age with good image quality achieved on almost all patients after 26 weeks. Conclusions: T2*-weighted GRE imaging can provide adequate fetal “black bone” contrast and performs at least as well as other sequences in the literature due to good bone to soft tissue contrast and minimal motion artefacts. Advances in knowledge: T2*-weighted fetal “black-bone” imaging can provide excellent bone to soft tissue contrast without using ionizing radiation. It is as good as other “black bone” sequences and may be simpler and more widely implemented, with less motion artefacts.

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Fearnhead, R. W., M. Pang, N. Mok e K. Kawasaki. "New Artefacts for Old: An Alternative Method of Preparing Hard and Soft Tissue Interfaces of Developing Enamel". Advances in Dental Research 1, n.º 2 (dezembro de 1987): 366–70. http://dx.doi.org/10.1177/08959374870010022801.

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Serial sections (each from 150 to 200 μm thick) of porcine molar tooth germs within their bony crypts, rodent incisor teeth (in situ), and human extracted teeth were cut with a thin rotating diamond-impregnated disc, without prior embedding. Some specimens were cut unfixed, at room temperature (21°C) or frozen (-70°C), some in fixative, and others cut after fixation. A variety of routine fixatives has been tried, and in general the preservation of hard/soft tissue interfaces is best achieved when fixation precedes cutting. Several histological and histochemical methods have also been tried successfully. The damaged surface layers of the specimens brought about by the cutting disc can be removed after staining, if the section is embedded in a thin sheet of Epon and then thinned by being polished. The method provides a novel way of studying hard/soft tissue junctions.

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Van Nimmen, Katrien, Guoping Zhao, André Seyfarth e Peter Van den Broeck. "A Robust Methodology for the Reconstruction of the Vertical Pedestrian-Induced Load from the Registered Body Motion". Vibration 1, n.º 2 (7 de novembro de 2018): 250–68. http://dx.doi.org/10.3390/vibration1020018.

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This paper proposes a methodology to reconstruct the vertical GRFs from the registered body motion that is reasonably robust against measurement noise. The vertical GRFs are reconstructed from the experimentally identified time-variant pacing rate and a generalised single-step load model available in the literature. The proposed methodology only requires accurately capturing the body motion within the frequency range 1–10 Hz and does not rely on the exact magnitude of the registered signal. The methodology can therefore also be applied when low-cost sensors are used and to minimize the impact of soft-tissue artefacts. In addition, the proposed procedure can be applied regardless of the position of the sensor on the human body, as long as the recorded body motion allows for identifying the time of a nominally identical event in successive walking cycles. The methodology is illustrated by a numerical example and applied to an experimental dataset where the ground reaction forces and the body motion were registered simultaneously. The results show that the proposed methodology allows for arriving at a good estimate of the vertical ground reaction forces. When the impact of soft-tissue artefacts is low, a comparable estimate can be obtained using Newton’s second law of motion.

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Camomilla, Valentina, Andrea Cereatti, Laurence Chèze e Aurelio Cappozzo. "A hip joint kinematics driven model for the generation of realistic thigh soft tissue artefacts". Journal of Biomechanics 46, n.º 3 (fevereiro de 2013): 625–30. http://dx.doi.org/10.1016/j.jbiomech.2012.09.018.

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Bonci, T., V. Camomilla, R. Dumas e A. Cappozzo. "Generation of realistic thigh soft tissue artefacts as a function of hip and knee kinematics". Gait & Posture 39 (junho de 2014): S72—S73. http://dx.doi.org/10.1016/j.gaitpost.2014.04.099.

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Lamberto, Giuliano, Saulo Martelli, Aurelio Cappozzo e Claudia Mazzà. "To what extent is joint and muscle mechanics predicted by musculoskeletal models sensitive to soft tissue artefacts?" Journal of Biomechanics 62 (setembro de 2017): 68–76. http://dx.doi.org/10.1016/j.jbiomech.2016.07.042.

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De Rosario, Helios, Álvaro Page e Antonio Besa. "Analytical study of the effects of soft tissue artefacts on functional techniques to define axes of rotation". Journal of Biomechanics 62 (setembro de 2017): 60–67. http://dx.doi.org/10.1016/j.jbiomech.2017.01.046.

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Laux, Christoph J., Christina Villefort, Stefanie Ehrbar, Lotte Wilke, Matthias Guckenberger e Daniel A. Müller. "Carbon Fiber/Polyether Ether Ketone (CF/PEEK) Implants Allow for More Effective Radiation in Long Bones". Materials 13, n.º 7 (9 de abril de 2020): 1754. http://dx.doi.org/10.3390/ma13071754.

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Background: Metallic implants show dose-modulating effects in radiotherapy and complicate its computed tomography (CT)-based planning. Dose deviations might not only affect the surrounding tissues due to backscattering and inadvertent dose increase but might also compromise the therapeutic effect to the target lesion due to beam attenuation. Later on, follow-up imaging is often obscured by metallic artefacts. Purposes: This study investigates the dosimetric impact of titanium and radiolucent carbon fiber/polyether ether ketone (CF/PEEK) implants during adjuvant radiation therapy in long bones. (1) Does the use of CF/PEEK implants allow for a more homogenous application of radiation? (2) Is the dose delivery to the target volume more efficient when using CF/PEEK implants? (3) Do CF/PEEK implants facilitate CT-based radiation therapy planning? Materials and methods: After CT-based planning, bone models of six ovine femora were irradiated within a water phantom in two immersion depths to simulate different soft-tissue envelopes. Plates and intramedullary nails of both titanium and CF/PEEK were investigated. Radiation dosage and distribution patterns were mapped using dosimetry films. Results: First, the planned implant-related beam attenuation was lower for the CF/PEEK plate (1% vs. 5%) and the CF/PEEK nail (2% vs. 9%) than for corresponding titanium implants. Secondly, the effective decrease of radiation dosage behind the implants was noticeably smaller when using CF/PEEK implants. The radiation dose was not significantly affected by the amount of surrounding soft tissues. A significant imaging artefact reduction was seen in all CF/PEEK models. Conclusion: CF/PEEK implants lead to a more reliable and more effective delivery of radiation dose to an osseous target volume. With regard to radiation therapy, the use of CF/PEEK implants appears to be particularly beneficial for intramedullary nails.

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S, Abirami. "Efficacy of cyanoacrylate adhesive as a mounting medium for soft tissue sections as an alternative to Kirkpatrick and Lendrum's DPX". International Journal of Clinicopathological Correlation 7, n.º 1 (18 de maio de 2023): 18–21. http://dx.doi.org/10.56501/intjclinicopatholcorrel.v7i1.840.

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Introduction: Mounting is the final stage in histologically preparing a slide and creates a permanent the bond between the coverslip and the slide, preventing breakage, air drying artefacts, and stain fading. Materials & methods: In this study, fifty slides were prepared, twenty-five of which were mounted using DPX and twenty five using cyanoacrylate adhesive. The slides were assessed for clarity of nuclear and cytoplasmic details, adhesion between coverslip and slide, and the presence of air bubbles by two blinded observers. Results: The results showed that adhesion between coverslip and slide was better when mounted with cyanoacrylate adhesive, but better clarity of nuclear and cytoplasmic details and minimal air bubble entrapment was seen when tissue sections were mounted using DPX. Conclusion: Therefore, the use of cyanoacrylate adhesive cannot be an alternative to DPX for mounting soft tissue sections.

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Shivam, Rachael, Sheelagh Rogers e Nicholas Drage. "An Evidence-based Protocol for the Management of Orthodontic Patients Undergoing MRI Scans". Orthodontic Update 14, n.º 1 (2 de janeiro de 2021): 32–35. http://dx.doi.org/10.12968/ortu.2021.14.1.32.

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Magnetic resonance imaging (MRI) uses strong magnetic fields, magnetic gradients and radio waves to produce images of the body. The demand for MRI is steadily increasing as it does not use ionizing radiation and has excellent soft tissue contrast. Certain materials used in components of fixed orthodontic appliances can cause unwanted effects and affect the diagnostic quality of MR images by producing artefacts. This article proposes an evidence-based protocol that aims to standardize the management of orthodontic patients undergoing MRI scans. CPD/Clinical Relevance: As the use of MRI continues to increase, it is becoming more likely that orthodontists will encounter patients requiring MRI scans of the head and neck region during the course of their orthodontic treatment.

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Li, Jia-Da, Tung-Wu Lu, Cheng-Chung Lin, Mei-Ying Kuo, Horng-Chaung Hsu e Wu-Chung Shen. "Soft tissue artefacts of skin markers on the lower limb during cycling: Effects of joint angles and pedal resistance". Journal of Biomechanics 62 (setembro de 2017): 27–38. http://dx.doi.org/10.1016/j.jbiomech.2017.03.018.

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Liney, Gary P., Jenny E. Marsden, Carl J. Horsfield, Tom Murray, David J. Manton e Andrew W. Beavis. "Improved visualisation of cervix applicators for magnetic resonance-only-guided brachytherapy planning". Journal of Radiotherapy in Practice 13, n.º 2 (22 de janeiro de 2014): 159–65. http://dx.doi.org/10.1017/s1460396913000514.

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AbstractObjectivesCurrent guidelines for image-guided cervical cancer brachytherapy planning recommend both computed tomography (CT) and magnetic resonance imaging (MRI) for adequate visualisation of the applicator and soft tissues, respectively. MRI-only planning would be ideal as it would save time within the patient pathway and avoid the concomitant CT exposures. However, applicator visualisation on MRI is usually achieved using fluid-filled fiducial marker tubes, which can be awkward to use and suffer from unwanted air bubble artefacts. Therefore, a new fiducial-free imaging technique was developed.MethodsA dual echo time (TE) turbo spin echo sequence was used, at 1·5 T, to provide both T2-weighted images (100 ms TE) for tissue visualisation and strongly proton density-weighted images (17 ms TE) for improved applicator visualisation. In-house software was used to automatically segment the applicator in the short TE images (using Otsu's method) and transfer the information to the long TE images to provide a single fused dataset.ResultsThe method was evaluated successfully using titanium applicators in three patient cases and using a plastic applicator in a tissue-equivalent gel phantom.ConclusionsThe dual-echo technique provides a simple and efficient method for improving the visualisation of brachytherapy applicators in cervical cancer MRI images without the need for marker tubes.

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Achene, A., M. Conti e G. C. Canalis. "Anatomia TC ed RM della regione orbitaria". Rivista di Neuroradiologia 13, n.º 3 (junho de 2000): 427–34. http://dx.doi.org/10.1177/197140090001300312.

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Pur non sottovalutando il ruolo degli US, la TC e la RM mostrano un ruolo di primo piano nella valutazione delle strutture ossee e del contenuto orbitario. Although ophthalmoscopy, fluoro-angiography and ultrasound can usually identify most bulbar lesions, CT and MR play a major role in assessing the bony orbital structures and the post-bulbar soft tissues. These imaging techniques are especially important in investigating the eyeball under conditions “blind” to ultrasound not transparent to dioptric instruments (blood in the vitreous body, cataract, corneal opacity) or to define the site and extension and sometimes the nature (melanoma) of tumours. Whereas both CT and MR are completely reliable techniques in the study of the orbit, overall CT is decidedly superior to MR in the study of bony structures and MR is the method of choice in assessing the endo-orbital contents. This is because MR offers better spatial resolution and contrast with multiplanar views (allowing study on three planes without requiring the patient to assume uncomfortable positions for coronal CT scanning), greater sensitivity to tissue changes and hence diseases, the lack of signal from bony tissue (displaying the content of small structures like the orbital apex, nasolacrimal fossa and optic canal which are difficult to assess by CT due to artefacts) and lastly, the absence of ionizing radiation in examining children. These advantages are flanked by the use of the fast-imaging technique and surface coils (phased-array) which have overcome the limitations originally linked with MR due to the prolonged examination times and images degraded by artefacts. Nowadays, the only obstacle to routine use of MR is the shortage of MR systems in Italy. For both MR and CT scanning, technological developments have led to significant advances with the advent of the spiral technique which reduces the artefacts of eyeball movements because anatomical volumes can be investigated rapidly, improving patient compliance (in acquiring coronal scans) and enhancing the quality of two and three-dimensional reconstructions and allowing optimum use of contrast medium as the structure can be scanned during the maximum increase phase with a reduction in the total amount of contrast administered. Although the spiral technique is seldom used to examine the orbit in adults given the small volume to investigate, it is particular indicated in uncooperative patients (children or trauma patients).

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Wong, Yi-Li, Vomanasri Krishnan, Norliza Ibrahim e Mohamad Helmee Mohamad Noor. "Application of Postmortem Radiographs: Advantages & Disadvantages". Journal of Clinical and Health Sciences 6, n.º 1(Special) (30 de junho de 2021): 52. http://dx.doi.org/10.24191/jchs.v6i1(special).13164.

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Postmortem radiograph skeletal surveys serve as imaging adjuncts to autopsy and forensic documentation in hospitals with no available forensic computed tomography and magnetic resonance imaging services. Despite this, modern literature pertaining practical applications of postmortem radiographs have gradually been superseded by interests in advanced imaging modalities. The main advantages are characterizing or excluding violent traumatic bone fractures or abnormalities, locating foreign bodies, identifying medical devices as well as acting as secondary adjuncts to anthropologic assessment. Limitations that test diagnostic value of postmortem radiographs include lack of direct visualization of soft tissue as well aspostmortem artefacts that obscure natural causes of death and can be misinterpreted as antemortem pathology. The roles and limitations of postmortem radiographs are illustrated in a case of a decomposed but complete and identified adult male decedent with reference to autopsy findings and literature review.

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Tariq, Briya, Osama Sikander, Nadine Francis, Manar Alkhatib, Farhat Naseer, Naoufel Werghi, Esat Memisoglu, Nabil Maalej e Aamir Raja. "Assessment of material identification and quantification in the presence of metals using spectral photon counting CT". PLOS ONE 19, n.º 9 (13 de setembro de 2024): e0308658. http://dx.doi.org/10.1371/journal.pone.0308658.

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Spectral Photon Counting Computed Tomography (SPCCT), a ground-breaking development in CT technology, has immense potential to address the persistent problem of metal artefacts in CT images. This study aims to evaluate the potential of Mars photon-counting CT technology in reducing metal artefacts. It focuses on identifying and quantifying clinically significant materials in the presence of metal objects. A multi-material phantom was used, containing inserts of varying concentrations of hydroxyapatite (a mineral present in teeth, bones, and calcified plaque), iodine (used as a contrast agent), CT water (to mimic soft tissue), and adipose (as a fat substitute). Three sets of scans were acquired: with aluminium, with stainless steel, and without a metal insert as a reference dataset. Data acquisition was performed using a Mars SPCCT scanner (Microlab 5×120); operated at 118 kVp and 80 μA. The images were subsequently reconstructed into five energy bins: 7-40, 40-50, 50-60, 60-79, and 79-118 keV. Evaluation metrics including signal-to-noise ratio (SNR), linearity of attenuation profiles, root mean square error (RMSE), and area under the curve (AUC) were employed to assess the energy and material-density images with and without metal inserts. Results show decreased metal artefacts and a better signal-to-noise ratio (up to 25%) with increased energy bins as compared to reference data. The attenuation profile also demonstrated high linearity (R2 >0.95) and lower RMSE across all material concentrations, even in the presence of aluminium and steel. Material identification accuracy for iodine and hydroxyapatite (with and without metal inserts) remained consistent, minimally impacting AUC values. For demonstration purposes, the biological sample was also scanned with the stainless steel volar implant and cortical bone screw, and the images were objectively assessed to indicate the potential effectiveness of SPCCT in replicating real-world clinical scenarios.

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Holler, Mirko, Johannes Ihli, Esther H. R. Tsai, Fabio Nudelman, Mariana Verezhak, Wilma D. J. van de Berg e Sarah H. Shahmoradian. "A lathe system for micrometre-sized cylindrical sample preparation at room and cryogenic temperatures". Journal of Synchrotron Radiation 27, n.º 2 (29 de janeiro de 2020): 472–76. http://dx.doi.org/10.1107/s1600577519017028.

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A simple two-spindle based lathe system for the preparation of cylindrical samples intended for X-ray tomography is presented. The setup can operate at room temperature as well as under cryogenic conditions, allowing the preparation of samples down to 20 and 50 µm in diameter, respectively, within minutes. Case studies are presented involving the preparation of a brittle biomineral brachiopod shell and cryogenically fixed soft brain tissue, and their examination by means of ptychographic X-ray computed tomography reveals the preparation method to be mainly free from causing artefacts. Since this lathe system easily yields near-cylindrical samples ideal for tomography, a usage for a wide variety of otherwise challenging specimens is anticipated, in addition to potential use as a time- and cost-saving tool prior to focused ion-beam milling. Fast sample preparation becomes especially important in relation to shorter measurement times expected in next-generation synchrotron sources.

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Serrien, Ben, Todd Pataky, Jean-Pierre Baeyens e Erik Cattrysse. "Bayesian vs. least-squares inverse kinematics: Simulation experiments with models of 3D rigid body motion and 2D models including soft-tissue artefacts". Journal of Biomechanics 109 (agosto de 2020): 109902. http://dx.doi.org/10.1016/j.jbiomech.2020.109902.

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Fragu, Philippe. "How SIMS microscopy can be used in medicine". Proceedings, annual meeting, Electron Microscopy Society of America 50, n.º 2 (agosto de 1992): 1602–3. http://dx.doi.org/10.1017/s0424820100132649.

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The identification, localization and quantification of intracellular chemical elements is an area of scientific endeavour which has not ceased to develop over the past 30 years. Secondary Ion Mass Spectrometry (SIMS) microscopy is widely used for elemental localization problems in geochemistry, metallurgy and electronics. Although the first commercial instruments were available in 1968, biological applications have been gradual as investigators have systematically examined the potential source of artefacts inherent in the method and sought to develop strategies for the analysis of soft biological material with a lateral resolution equivalent to that of the light microscope. In 1992, the prospects offered by this technique are even more encouraging as prototypes of new ion probes appear capable of achieving the ultimate goal, namely the quantitative analysis of micron and submicron regions. The purpose of this review is to underline the requirements for biomedical applications of SIMS microscopy.Sample preparation methodology should preserve both the structural and the chemical integrity of the tissue.

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Gray, C. F., T. W. Redpath e F. W. Smith. "Low-field magnetic resonance imaging for implant dentistry". Dentomaxillofacial Radiology 27, n.º 4 (1 de julho de 1998): 225–29. http://dx.doi.org/10.1038/sj/dmfr/4600355.

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OBJECTIVE To evaluate the use of a low-field magnetic resonance scanner for assessment of available bone for placement of osseo-integrated dental implants. METHODS Eleven Patients were examined to assess suitability for implant placement using a 0.2 tesla 'open' scanner. Imaging/surgical templates were constructed, with gadolinium markers to allow accurate location of the implant sites. RESULTS In all cases, localisation of potential implant sites was easily made and full information in all three planes readily available. Artefacts were few and localised, (noted on one site in one case only). Vital structures (nerves and vessels), and the variable geometry of the floor of the maxillary sinus were clearly seen, and cortical bone delineated from cancellous. The appearance of soft tissues in the scan allowed the surgeon to assess the final profile of the patient. CONCLUSION Low-field magnetic resonance imaging has definite potential for pre-implant assessment. Full sectional information is readily available at any desired plane with no need for reformatting. The information for accurate and safe implant placement is clear. The technique uses no ionising radiation. Further work is needed to evaluate spatial distortion caused by magnetic susceptibility effects at air/tissue interfaces, but our calculations indicate that at low field, using an appropriate protocol, the effect will not be substantial.

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Andersen, Michael S., Daniel L. Benoit, Michael Damsgaard, Dan K. Ramsey e John Rasmussen. "Do kinematic models reduce the effects of soft tissue artefacts in skin marker-based motion analysis? An in vivo study of knee kinematics". Journal of Biomechanics 43, n.º 2 (janeiro de 2010): 268–73. http://dx.doi.org/10.1016/j.jbiomech.2009.08.034.

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Zemp, Roland, Renate List, Turgut Gülay, Jean Pierre Elsig, Jaroslav Naxera, William R. Taylor e Silvio Lorenzetti. "Soft Tissue Artefacts of the Human Back: Comparison of the Sagittal Curvature of the Spine Measured Using Skin Markers and an Open Upright MRI". PLoS ONE 9, n.º 4 (18 de abril de 2014): e95426. http://dx.doi.org/10.1371/journal.pone.0095426.

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Mayer, Johannes, Thomas-Heinrich Wurster, Tobias Schaeffter, Ulf Landmesser, Andreas Morguet, Boris Bigalke, Bernd Hamm, Winfried Brenner, Marcus R. Makowski e Christoph Kolbitsch. "Imaging coronary plaques using 3D motion-compensated [18F]NaF PET/MR". European Journal of Nuclear Medicine and Molecular Imaging 48, n.º 8 (21 de janeiro de 2021): 2455–65. http://dx.doi.org/10.1007/s00259-020-05180-4.

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Abstract Background Cardiac PET has recently found novel applications in coronary atherosclerosis imaging using [18F]NaF as a radiotracer, highlighting vulnerable plaques. However, the resulting uptakes are relatively small, and cardiac motion and respiration-induced movement of the heart can impair the reconstructed images due to motion blurring and attenuation correction mismatches. This study aimed to apply an MR-based motion compensation framework to [18F]NaF data yielding high-resolution motion-compensated PET and MR images. Methods Free-breathing 3-dimensional Dixon MR data were acquired, retrospectively binned into multiple respiratory and cardiac motion states, and split into fat and water fraction using a model-based reconstruction framework. From the dynamic MR reconstructions, both a non-rigid cardiorespiratory motion model and a motion-resolved attenuation map were generated and applied to the PET data to improve image quality. The approach was tested in 10 patients and focal tracer hotspots were evaluated concerning their target-to-background ratio, contrast-to-background ratio, and their diameter. Results MR-based motion models were successfully applied to compensate for physiological motion in both PET and MR. Target-to-background ratios of identified plaques improved by 7 ± 7%, contrast-to-background ratios by 26 ± 38%, and the plaque diameter decreased by −22 ± 18%. MR-based dynamic attenuation correction strongly reduced attenuation correction artefacts and was not affected by stent-related signal voids in the underlying MR reconstructions. Conclusions The MR-based motion correction framework presented here can improve the target-to-background, contrast-to-background, and width of focal tracer hotspots in the coronary system. The dynamic attenuation correction could effectively mitigate the risk of attenuation correction artefacts in the coronaries at the lung-soft tissue boundary. In combination, this could enable a more reproducible and reliable plaque localisation.

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Rowe, Nick P., Lily Cheng Clavel e Patricia Soffiatti. "Failure without Tears: Two-Step Attachment in a Climbing Cactus". Biomimetics 8, n.º 2 (25 de maio de 2023): 220. http://dx.doi.org/10.3390/biomimetics8020220.

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Climbing plants can be extremely adaptable to diverse habitats and capable of colonising perturbed, unstructured, and even moving environments. The timing of the attachment process, whether instantaneous (e.g., a pre-formed hook) or slow (growth process), crucially depends on the environmental context and the evolutionary history of the group concerned. We observed how spines and adhesive roots develop and tested their mechanical strength in the climbing cactus Selenicereus setaceus (Cactaceae) in its natural habitat. Spines are formed on the edges of the triangular cross-section of the climbing stem and originate in soft axillary buds (areoles). Roots are formed in the inner hard core of the stem (wood cylinder) and grow via tunnelling through soft tissue, emerging from the outer skin. We measured maximal spine strength and root strength via simple tensile tests using a field measuring Instron device. Spine and root strengths differ, and this has a biological significance for the support of the stem. Our measurements indicate that the measured mean strength of a single spine could theoretically support an average force of 2.8 N. This corresponds to an equivalent stem length of 2.62 m (mass of 285 g). The measured mean strength of root could theoretically support an average of 13.71 N. This corresponds to a stem length of 12.91 m (mass of 1398 g). We introduce the notion of two-step attachment in climbing plants. In this cactus, the first step deploys hooks that attach to a substrate; this process is instantaneous and is highly adapted for moving environments. The second step involves more solid root attachment to the substrate involving slower growth processes. We discuss how initial fast hook attachment can steady the plant on supports allowing for the slower root attachment. This is likely to be important in wind-prone and moving environmental conditions. We also explore how two-step anchoring mechanisms are of interest for technical applications, particularly for soft-bodied artefacts, which must safely deploy hard and stiff materials originating from a soft compliant body.

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Zhu, Q. A., Y. B. Park, S. G. Sjovold, C. A. Niosi, D. C. Wilson, P. A. Cripton e T. R. Oxland. "Can extra-articular strains be used to measure facet contact forces in the lumbar spine? An in-vitro biomechanical study". Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 222, n.º 2 (1 de fevereiro de 2008): 171–84. http://dx.doi.org/10.1243/09544119jeim290.

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Experimental measurement of the load-bearing patterns of the facet joints in the lumbar spine remains a challenge, thereby limiting the assessment of facet joint function under various surgical conditions and the validation of computational models. The extra-articular strain (EAS) technique, a non-invasive measurement of the contact load, has been used for unilateral facet joints but does not incorporate strain coupling, i.e. ipsilateral EASs due to forces on the contralateral facet joint. The objectives of the present study were to establish a bilateral model for facet contact force measurement using the EAS technique and to determine its effectiveness in measuring these facet joint contact forces during three-dimensional flexibility tests in the lumbar spine. Specific goals were to assess the accuracy and repeatability of the technique and to assess the effect of soft-tissue artefacts. In the accuracy and repeatability tests, ten uniaxial strain gauges were bonded to the external surface of the inferior facets of L3 of ten fresh lumbar spine specimens. Two pressure-sensitive sensors (Tekscan) were inserted into the joints after the capsules were cut. Facet contact forces were measured with the EAS and Tekscan techniques for each specimen in flexion, extension, axial rotation, and lateral bending under a ±7.5 N m pure moment. Four of the ten specimens were tested five times in axial rotation and extension for repeatability. These same specimens were disarticulated and known forces were applied across the facet joint using a manual probe (direct accuracy) and a materials-testing system (disarticulated accuracy). In soft-tissue artefact tests, a separate set of six lumbar spine specimens was used to document the virtual facet joint contact forces during a flexibility test following removal of the superior facet processes. Linear strain coupling was observed in all specimens. The average peak facet joint contact forces during flexibility testing was greatest in axial rotation (71±25 N), followed by extension (27±35 N) and lateral bending (25±28 N), and they were most repeatable in axial rotation (coefficient of variation, 5 per cent). The EAS accuracy was about 20 per cent in the direct accuracy assessment and about 30 per cent in the disarticulated accuracy test. The latter was very similar to the Tekscan accuracy in the same test. Virtual facet loads (r.m.s.) were small in axial rotation (12 N) and lateral bending (20 N), but relatively large in flexion (34 N) and extension (35 N). The results suggested that the bilateral EAS model could be used to determine the facet joint contact forces in axial rotation but may result in considerable error in flexion, extension, and lateral bending.

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Vogl, Florian, Pascal Schütz, Barbara Postolka, Renate List e William Taylor. "Personalised pose estimation from single-plane moving fluoroscope images using deep convolutional neural networks". PLOS ONE 17, n.º 6 (24 de junho de 2022): e0270596. http://dx.doi.org/10.1371/journal.pone.0270596.

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Measuring joint kinematics is a key requirement for a plethora of biomechanical research and applications. While x-ray based systems avoid the soft-tissue artefacts arising in skin-based measurement systems, extracting the object’s pose (translation and rotation) from the x-ray images is a time-consuming and expensive task. Based on about 106’000 annotated images of knee implants, collected over the last decade with our moving fluoroscope during activities of daily living, we trained a deep-learning model to automatically estimate the 6D poses for the femoral and tibial implant components. By pretraining a single stage of our architecture using renderings of the implant geometries, our approach offers personalised predictions of the implant poses, even for unseen subjects. Our approach predicted the pose of both implant components better than about 0.75 mm (in-plane translation), 25 mm (out-of-plane translation), and 2° (all Euler-angle rotations) over 50% of the test samples. When evaluating over 90% of test samples, which included heavy occlusions and low contrast images, translation performance was better than 1.5 mm (in-plane) and 30 mm (out-of-plane), while rotations were predicted better than 3−4°. Importantly, this approach now allows for pose estimation in a fully automated manner.

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Potter, Michael V., Stephen M. Cain, Lauro V. Ojeda, Reed D. Gurchiek, Ryan S. McGinnis e Noel C. Perkins. "Error-state Kalman filter for lower-limb kinematic estimation: Evaluation on a 3-body model". PLOS ONE 16, n.º 4 (20 de abril de 2021): e0249577. http://dx.doi.org/10.1371/journal.pone.0249577.

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Human lower-limb kinematic measurements are critical for many applications including gait analysis, enhancing athletic performance, reducing or monitoring injury risk, augmenting warfighter performance, and monitoring elderly fall risk, among others. We present a new method to estimate lower-limb kinematics using an error-state Kalman filter that utilizes an array of body-worn inertial measurement units (IMUs) and four kinematic constraints. We evaluate the method on a simplified 3-body model of the lower limbs (pelvis and two legs) during walking using data from simulation and experiment. Evaluation on this 3-body model permits direct evaluation of the ErKF method without several confounding error sources from human subjects (e.g., soft tissue artefacts and determination of anatomical frames). RMS differences for the three estimated hip joint angles all remain below 0.2 degrees compared to simulation and 1.4 degrees compared to experimental optical motion capture (MOCAP). RMS differences for stride length and step width remain within 1% and 4%, respectively compared to simulation and 7% and 5%, respectively compared to experiment (MOCAP). The results are particularly important because they foretell future success in advancing this approach to more complex models for human movement. In particular, our future work aims to extend this approach to a 7-body model of the human lower limbs composed of the pelvis, thighs, shanks, and feet.

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Salmon, Phil, e Alexander Sasov. "Towards intraoperative microCT imaging of breast cancer resections." Journal of Clinical Oncology 33, n.º 28_suppl (1 de outubro de 2015): 147. http://dx.doi.org/10.1200/jco.2015.33.28_suppl.147.

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147 Background: MicroCT analysis of breast cancer resections was shown by Rong et al. [Tang R et al. (2013) The Breast Journal 19(5), 485-489; Tang R et al. (2013) Breast Cancer Research and Treatment 139(2), 311-316] to attain equivalence with pathology-histology in the assessment of positive margin. However, Rong et al. noted that the 14 minute scan cycle time–7 minutes scan, 7 minutes reconstruction–was a potential limitation. Methods: This paper reports the development of microCT instrumentation and software to address this and other technical challenges. These include (a) reducing the scan-reconstruction time, (b) a small desktop footprint, (c) reconciling optimal soft tissue contrast with minimizing artefacts from inserted metal wires and large calcifications, and (d) features to aid hospital workflow such as a barcode reader, an optical camera to photograph the specimen, and process automation. Scans were done with the purpose-built SkyScan1275 table-top microCT scanner, on frozen anonymous archived breast cancer resection samples. Results: Minimum scan time retaining acceptable image quality was 3 minutes. Reconstruction time was reduced to less than a minute by PC graphics accelerators. Scan-reconstruction cycle time can thus be < 4 minutes. A small (105 x 64 cm) desktop footprint with a weight of 160 kg, requiring only a sturdy laboratory desk, has also been attained in this scanner. Artefacts from large calcifications and metal wires were reduced to non-obtrusive levels by scanning with 1mm aluminum filter and software techniques. An automated scan sequence was developed with sample holders recognized electronically in the scanner. On pressing a single button, the scanner automatically goes to the appropriate magnification and sample height, scans the sample, then reconstructs the scan with preset parameters, and finally opens the reconstructed dataset in software for interactive volume-rendered viewing. Sample barcode reading and optical photo taking can be included in this auto-scan sequence. Conclusions: These developments bring microCT nearer to realizing its potential as an intraoperative “back-table” technique in breast cancer surgery to obviate revisions and improve the surgery process and outcome.

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Hindle, Benjamin R., Justin W. L. Keogh e Anna V. Lorimer. "Inertial-Based Human Motion Capture: A Technical Summary of Current Processing Methodologies for Spatiotemporal and Kinematic Measures". Applied Bionics and Biomechanics 2021 (26 de março de 2021): 1–14. http://dx.doi.org/10.1155/2021/6628320.

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Inertial-based motion capture (IMC) has been suggested to overcome many of the limitations of traditional motion capture systems. The validity of IMC is, however, suggested to be dependent on the methodologies used to process the raw data collected by the inertial device. The aim of this technical summary is to provide researchers and developers with a starting point from which to further develop the current IMC data processing methodologies used to estimate human spatiotemporal and kinematic measures. The main workflow pertaining to the estimation of spatiotemporal and kinematic measures was presented, and a general overview of previous methodologies used for each stage of data processing was provided. For the estimation of spatiotemporal measures, which includes stride length, stride rate, and stance/swing duration, measurement thresholding and zero-velocity update approaches were discussed as the most common methodologies used to estimate such measures. The methodologies used for the estimation of joint kinematics were found to be broad, with the combination of Kalman filtering or complimentary filtering and various sensor to segment alignment techniques including anatomical alignment, static calibration, and functional calibration methods identified as being most common. The effect of soft tissue artefacts, device placement, biomechanical modelling methods, and ferromagnetic interference within the environment, on the accuracy and validity of IMC, was also discussed. Where a range of methods have previously been used to estimate human spatiotemporal and kinematic measures, further development is required to reduce estimation errors, improve the validity of spatiotemporal and kinematic estimations, and standardize data processing practices. It is anticipated that this technical summary will reduce the time researchers and developers require to establish the fundamental methodological components of IMC prior to commencing further development of IMC methodologies, thus increasing the rate of development and utilisation of IMC.

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Dumas, R., V. Camomilla, T. Bonci, L. Cheze e A. Cappozzo. "Generalized mathematical representation of the soft tissue artefact". Journal of Biomechanics 47, n.º 2 (janeiro de 2014): 476–81. http://dx.doi.org/10.1016/j.jbiomech.2013.10.034.

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Camomilla, Valentina, Raphaël Dumas e Aurelio Cappozzo. "Human movement analysis: The soft tissue artefact issue". Journal of Biomechanics 62 (setembro de 2017): 1–4. http://dx.doi.org/10.1016/j.jbiomech.2017.09.001.

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Cutti, Andrea Giovanni, Gabriele Paolini, Marco Troncossi, Angelo Cappello e Angelo Davalli. "Soft tissue artefact assessment in humeral axial rotation". Gait & Posture 21, n.º 3 (abril de 2005): 341–49. http://dx.doi.org/10.1016/j.gaitpost.2004.04.001.

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Camomilla, V., T. Bonci, R. Dumas, L. Chèze e A. Cappozzo. "A model of the soft tissue artefact rigid component". Journal of Biomechanics 48, n.º 10 (julho de 2015): 1752–59. http://dx.doi.org/10.1016/j.jbiomech.2015.05.007.

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Dumas, R., V. Camomilla, T. Bonci, L. Cheze e A. Cappozzo. "A qualitative analysis of soft tissue artefact during running". Computer Methods in Biomechanics and Biomedical Engineering 17, sup1 (30 de julho de 2014): 124–25. http://dx.doi.org/10.1080/10255842.2014.931518.

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Sagasser, Svenja, Adrian Sauer, Christoph Thorwächter, Jana G. Weber, Allan Maas, Matthias Woiczinski, Thomas M. Grupp e Ariana Ortigas-Vásquez. "Validation of Inertial-Measurement-Unit-Based Ex Vivo Knee Kinematics during a Loaded Squat before and after Reference-Frame-Orientation Optimisation". Sensors 24, n.º 11 (23 de maio de 2024): 3324. http://dx.doi.org/10.3390/s24113324.

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Recently, inertial measurement units have been gaining popularity as a potential alternative to optical motion capture systems in the analysis of joint kinematics. In a previous study, the accuracy of knee joint angles calculated from inertial data and an extended Kalman filter and smoother algorithm was tested using ground truth data originating from a joint simulator guided by fluoroscopy-based signals. Although high levels of accuracy were achieved, the experimental setup leveraged multiple iterations of the same movement pattern and an absence of soft tissue artefacts. Here, the algorithm is tested against an optical marker-based system in a more challenging setting, with single iterations of a loaded squat cycle simulated on seven cadaveric specimens on a force-controlled knee rig. Prior to the optimisation of local coordinate systems using the REference FRame Alignment MEthod (REFRAME) to account for the effect of differences in local reference frame orientation, root-mean-square errors between the kinematic signals of the inertial and optical systems were as high as 3.8° ± 3.5° for flexion/extension, 20.4° ± 10.0° for abduction/adduction and 8.6° ± 5.7° for external/internal rotation. After REFRAME implementation, however, average root-mean-square errors decreased to 0.9° ± 0.4° and to 1.5° ± 0.7° for abduction/adduction and for external/internal rotation, respectively, with a slight increase to 4.2° ± 3.6° for flexion/extension. While these results demonstrate promising potential in the approach’s ability to estimate knee joint angles during a single loaded squat cycle, they highlight the limiting effects that a reduced number of iterations and the lack of a reliable consistent reference pose inflicts on the sensor fusion algorithm’s performance. They similarly stress the importance of adapting underlying assumptions and correctly tuning filter parameters to ensure satisfactory performance. More importantly, our findings emphasise the notable impact that properly aligning reference-frame orientations before comparing joint kinematics can have on results and the conclusions derived from them.

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Zhang, Qiang, Naomi C. Adam, S. H. Hosseini Nasab, William R. Taylor e Colin R. Smith. "Techniques for In Vivo Measurement of Ligament and Tendon Strain: A Review". Annals of Biomedical Engineering 49, n.º 1 (6 de outubro de 2020): 7–28. http://dx.doi.org/10.1007/s10439-020-02635-5.

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AbstractThe critical clinical and scientific insights achieved through knowledge of in vivo musculoskeletal soft tissue strains has motivated the development of relevant measurement techniques. This review provides a comprehensive summary of the key findings, limitations, and clinical impacts of these techniques to quantify musculoskeletal soft tissue strains during dynamic movements. Current technologies generally leverage three techniques to quantify in vivo strain patterns, including implantable strain sensors, virtual fibre elongation, and ultrasound. (1) Implantable strain sensors enable direct measurements of tissue strains with high accuracy and minimal artefact, but are highly invasive and current designs are not clinically viable. (2) The virtual fibre elongation method tracks the relative displacement of tissue attachments to measure strains in both deep and superficial tissues. However, the associated imaging techniques often require exposure to radiation, limit the activities that can be performed, and only quantify bone-to-bone tissue strains. (3) Ultrasound methods enable safe and non-invasive imaging of soft tissue deformation. However, ultrasound can only image superficial tissues, and measurements are confounded by out-of-plane tissue motion. Finally, all in vivo strain measurement methods are limited in their ability to establish the slack length of musculoskeletal soft tissue structures. Despite the many challenges and limitations of these measurement techniques, knowledge of in vivo soft tissue strain has led to improved clinical treatments for many musculoskeletal pathologies including anterior cruciate ligament reconstruction, Achilles tendon repair, and total knee replacement. This review provides a comprehensive understanding of these measurement techniques and identifies the key features of in vivo strain measurement that can facilitate innovative personalized sports medicine treatment.

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Camomilla, V., T. Bonci e A. Cappozzo. "Pelvis soft tissue artefact assessment during 3-D hip movements". Gait & Posture 42 (dezembro de 2015): S36—S37. http://dx.doi.org/10.1016/j.gaitpost.2015.03.070.

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Stagni, R., e S. Fantozzi. "Can cluster deformation be an indicator of soft tissue artefact?" Gait & Posture 30 (outubro de 2009): S55. http://dx.doi.org/10.1016/j.gaitpost.2009.07.050.

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Weber, Jana G., Ariana Ortigas-Vásquez, Adrian Sauer, Ingrid Dupraz, Michael Utz, Allan Maas e Thomas M. Grupp. "Comparison of IMU-Based Knee Kinematics with and without Harness Fixation against an Optical Marker-Based System". Bioengineering 11, n.º 10 (28 de setembro de 2024): 976. http://dx.doi.org/10.3390/bioengineering11100976.

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The use of inertial measurement units (IMUs) as an alternative to optical marker-based systems has the potential to make gait analysis part of the clinical standard of care. Previously, an IMU-based system leveraging Rauch–Tung–Striebel smoothing to estimate knee angles was assessed using a six-degrees-of-freedom joint simulator. In a clinical setting, however, accurately measuring abduction/adduction and external/internal rotation of the knee joint is particularly challenging, especially in the presence of soft tissue artefacts. In this study, the in vivo IMU-based joint angles of 40 asymptomatic knees were assessed during level walking, under two distinct sensor placement configurations: (1) IMUs fixed to a rigid harness, and (2) IMUs mounted on the skin using elastic hook-and-loop bands (from here on referred to as “skin-mounted IMUs”). Estimates were compared against values obtained from a harness-mounted optical marker-based system. The comparison of these three sets of kinematic signals (IMUs on harness, IMUs on skin, and optical markers on harness) was performed before and after implementation of a REference FRame Alignment MEthod (REFRAME) to account for the effects of differences in coordinate system orientations. Prior to the implementation of REFRAME, in comparison to optical estimates, skin-mounted IMU-based angles displayed mean root-mean-square errors (RMSEs) up to 6.5°, while mean RMSEs for angles based on harness-mounted IMUs peaked at 5.1°. After REFRAME implementation, peak mean RMSEs were reduced to 4.1°, and 1.5°, respectively. The negligible differences between harness-mounted IMUs and the optical system after REFRAME revealed that the IMU-based system was capable of capturing the same underlying motion pattern as the optical reference. In contrast, obvious differences between the skin-mounted IMUs and the optical reference indicated that the use of a harness led to fundamentally different joint motion being measured, even after accounting for reference frame misalignments. Fluctuations in the kinematic signals associated with harness use suggested the rigid device oscillated upon heel strike, likely due to inertial effects from its additional mass. Our study proposes that optical systems can be successfully replaced by more cost-effective IMUs with similar accuracy, but further investigation (especially in vivo and upon heel strike) against moving videofluoroscopy is recommended.

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Camomilla, Valentina, e Tecla Bonci. "A joint kinematics driven model of the pelvic soft tissue artefact". Journal of Biomechanics 111 (outubro de 2020): 109998. http://dx.doi.org/10.1016/j.jbiomech.2020.109998.

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Rouvier, T., C. Livet, A. Lombart, G. Dumont, C. Pontonnier, C. Sauret e H. Pillet. "Comparison of scapula soft tissue artefact compensation methods during manual wheelchair locomotion". Gait & Posture 97 (setembro de 2022): S233—S234. http://dx.doi.org/10.1016/j.gaitpost.2022.07.143.

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Richard, V., V. Camomilla, L. Cheze, A. Cappozzo e R. Dumas. "Feasibility of incorporating a soft tissue artefact model in multi-body optimisation". Computer Methods in Biomechanics and Biomedical Engineering 15, sup1 (setembro de 2012): 194–96. http://dx.doi.org/10.1080/10255842.2012.713667.

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Bonci, Tecla, Valentina Camomilla, Raphael Dumas, Laurence Chèze e Aurelio Cappozzo. "A soft tissue artefact model driven by proximal and distal joint kinematics". Journal of Biomechanics 47, n.º 10 (julho de 2014): 2354–61. http://dx.doi.org/10.1016/j.jbiomech.2014.04.029.

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