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1
Chethan, K. N., Shyamasunder N. Bhat, Mohammad Zuber e Satish B. Shenoy. "Patient-Specific Static Structural Analysis of Femur Bone of different lengths". Open Biomedical Engineering Journal 12, n. 1 (31 dicembre 2018): 108–14. http://dx.doi.org/10.2174/1874120701812010108.
Testo completoAbstract (sommario):
Background:The femur bone is an essential part of human activity, providing stability and support in carrying out our day to day activities. The inter-human anatomical variation and load bearing ability of humans of different heights will provide the necessary understanding of their functional ability.Objective:In this study, femur bone of two humans of different lengths (tall femur and short femur) were subjected to static structural loading conditions to evaluate their load-bearing abilities using Finite Element Analysis.Methods:The 3D models of femur bones were developed using MIMICS from the CT scans which were then subjected to static structural analysis by varying the load from 1000N to 8000N. The von Mises stress and deformation were captured to compare the performance of each of the femur bones.Results:The tall femur resulted in reduced Von-Mises stress and total deformation when compared to the short femur. However, the maximum principle stresses showed an increase with an increase in the bone length. In both the femurs, the maximum stresses were observed in the medullary region.Conclusion:When the applied load exceeds 10 times the body weight of the person, the tall femur model exceeded 134 MPa stress value. The short femur model failed at 9 times the body weight, indicating that the tall femur had higher load-bearing abilities.
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Desai, Utsavi Devang, Alka Udania, Purvi Desai, Haripriyanka Kotha e Shino Shajan. "Cross sectional analytical study – Analytical morphometric study of dry femur in South Gujarat". Indian Journal of Clinical Anatomy and Physiology 9, n. 4 (15 gennaio 2023): 252–56. http://dx.doi.org/10.18231/j.ijcap.2022.053.
Testo completoAbstract (sommario):
The femur is the longest, heaviest, and strongest bone in the human body. Morphometric study of femur can be useful for estimation of stature, prediction of femur fractures/pathologies, operative management as well as for determination of congenital anomalies. 250 dry femur bones collected from bone Store, Government Medical College, Surat, Gujarat with study done over a period of 6 months. Total length of each femur and the Foraminal Index (FI) for each nutrient foramina were obtained. The mean total length of femur obtained was 41.22 cms. Torsion angle for both right sided as well as left sided femurs was most common in the range 11 - 14. 39.7% (48) of the total right sided femurs (121) had a torsion angle in the range 11 - 14 while 41.9% (54) of the total left sided femurs (129) also had a torsion angle in the range 11 - 14. Maximum number had a neck shaft angle in the range of 123 - 127 which constitutes 41.6% (104) of total sample size. Nutrient foramina was most commonly (48.8%) along linea aspera with most had a size corresponding to 22 gauge, which constitutes 45.7% (119) of total sample size. Morphometric study of femur helps us to determine various factors which could be helpful for prediction, prevention and diagnosis of a certain pathology as well as for its management and treatment.
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Nawata, Shintaro, Matsuyoshi Ogawa, Yoshinobu Ishiwata, Naomi Kobayashi, Ayako Shishikura-Hino, Keisuke Yoshida, Yutaka Inaba, Tomoyuki Saito, Tomio Inoue e Tomohiro Kaneta. "Differences in sodium fluoride-18 uptake in the normal skeleton depending on the location and characteristics of the bone". Nuklearmedizin 56, n. 03 (2017): 91–96. http://dx.doi.org/10.3413/nukmed-0867-16-12.
Testo completoAbstract (sommario):
Summary Aim: The aim of this study was to evaluate the normal distribution of sodium fluoride-18 (NaF-18) and to clarify the differences in uptake according to location and the type of the bone using positron emission tomography (PET) / computed tomography (CT). Methods: We retrospectively reviewed NaF-18 PET/CT images from 30 patients with hip joint disorders. PET/CT scans were performed 40 min after injection of approximately 185 MBq of NaF-18. To evaluate the relationship between the distribution of NaF-18 uptake and bone density, we compared the maximum standardised uptake values (SUVmax) on PET and the Hounsfield Units (HUs) on CT of the lumbar vertebra, ilium, and proximal and distal femurs. Regions of interests were defined both outside and inside the cortical bone to measure whole bone and cancellous bone only, respectively. Results: The distribution of NaF-18 differed according to the skeletal site. The lumbar vertebra showed the highest SUVmax for both whole bone and cancellous bone, followed by the ilium, proximal femur, and distal femur. The bones differed significantly in SUVmax. The distal femur showed the highest HU, followed by the proximal femur, ilium, and vertebra. Profile curve analyses demonstrated that the cancellous bones showed higher SUVmax and lower HU than the cortical bones. Conclusions: Our results demonstrate the difference in NaF-18 uptake between cancellous and cortical bones, which may explain differences in uptake by location. NaF-18 uptake does not appear to be strongly correlated with bone density, but rather with bone turnover and blood flow.
4
Raab, D. M., E. L. Smith, T. D. Crenshaw e D. P. Thomas. "Bone mechanical properties after exercise training in young and old rats". Journal of Applied Physiology 68, n. 1 (1 gennaio 1990): 130–34. http://dx.doi.org/10.1152/jappl.1990.68.1.130.
Testo completoAbstract (sommario):
The effects of a 10-wk training regimen on the mechanical properties of the femur and humerus were evaluated in 2.5- and 25-mo-old Fischer 344 female rats. The rats trained on a rodent treadmill 5 days/wk for 10 wk. Duration, grade, and speed increased until the rats maintained 1 h/day at 15% grade and either 15 m/min (old rats) or 36 m/min (young rats). Excised bones were mechanically tested with a 3-point flexure test for mechanical properties of force, stress, and strain. Fat-free dry weight (FFW) and moment of inertia were also obtained. With aging, similar increases were observed in both the femur and humerus for FFW, moment of inertia, and force. Ultimate stress was reduced in the senescent femur while strain was elevated; a similar but nonsignificant trend was observed in the humerus. Irrespective of age, training increased FFW in the femur and, to a lesser degree, in the humerus. Breaking force was elevated for both bones after training. In young and old bones, the training-induced differences in bone mass and force were similar, despite differences in training intensity. In the old trained rats, femur ultimate stress was greater than that in control rat femurs and similar to that in young rat femurs. The results of the present study indicate that training effects were not limited by age.
5
Setiawan, Feny, Suryadiwansa Harun e Yanuar Burhanudin. "REKONSTRUKSI TULANG LUTUT MENJADI MODEL 3D IMPLAN FEMUR DENGAN METODE REVERSE ENGINEERING BERBASIS PEMINDAI X-RAY". Jurnal Rekayasa Mesin 13, n. 1 (18 giugno 2022): 67–75. http://dx.doi.org/10.21776/ub.jrm.2022.013.01.8.
Testo completoAbstract (sommario):
In order to obtain the geometry and size of bone implants that match the patient's original bone from this study, the patient femur knee bone is reconstructed into a 3D femur implant model using an X-Ray data scanner during Reverse Engineering (RE) process. In the process of RE, the femur knee bone was initially reconstructed by scanning its front and side view into a photo using the digital radiography system. For building a 3D model of the femur implant, the front and side view of the knee bones are sketched according to the dimensions and shape of the scanned femur knee bones. Then, one of the sketches is defined as the sketch profile of the femur knee bone, while the other is the trajectory profile. 3D modeling of the femur implant was constructed by using the sweep method in 3D design software. The results of this knee reconstruction obtained a 3D model of the femoral knee bone implant that is following the patient's bone shape.
6
Zdero, Radovan, Shaun Rose, Emil H. Schemitsch e Marcello Papini. "Cortical Screw Pullout Strength and Effective Shear Stress in Synthetic Third Generation Composite Femurs". Journal of Biomechanical Engineering 129, n. 2 (28 agosto 2006): 289–93. http://dx.doi.org/10.1115/1.2540926.
Testo completoAbstract (sommario):
Background: The use of artificial bone analogs in biomechanical testing of orthopaedic fracture fixation devices has increased, particularly due to the recent development of commercially available femurs such as the third generation composite femur that closely reproduce the bulk mechanical behavior of human cadaveric and∕or fresh whole bone. The purpose of this investigation was to measure bone screw pullout forces in composite femurs and determine whether results are comparable to cadaver data from previous literature. Method of Approach: The pullout strengths of 3.5 and 4.5mm standard bicortical screws inserted into synthetic third generation composite femurs were measured and compared to existing adult human cadaveric and animal data from the literature. Results: For 3.5mm screws, the measured extraction shear stress in synthetic femurs (23.70-33.99MPa) was in the range of adult human femurs and tibias (24.4-38.8MPa). For 4.5mm screws, the measured values in synthetic femurs (26.04-34.76MPa) were also similar to adult human specimens (15.9-38.9MPa). Synthetic femur results for extraction stress showed no statistically significant site-to-site effect for 3.5 and 4.5mm screws, with one exception. Overall, the 4.5mm screws showed statistically higher stress required for extraction than 3.5mm screws. Conclusions: The third generation composite femurs provide a satisfactory biomechanical analog to human long-bones at the screw-bone interface. However, it is not known whether these femurs perform similarly to human bone during physiological screw “toggling.”
7
MEYERS, F. "Femur bone densities". Lancet 341, n. 8861 (giugno 1993): 1662. http://dx.doi.org/10.1016/0140-6736(93)90794-h.
Testo completo
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Pastor, Felipe Martins, Gabriela de Oliveira Resende, Rejane Costa Alves, Louisiane de Carvalho Nunes, Guilherme Galhardo Franco, Jankerle Neves Boeloni, Rogéria Serakides e Maria Aparecida da Silva. "Mechanical behaviour of femur and humerus at the three-point bending and axial compression tests in the crab-eating fox (Cerdocyon thous, Linnaeus 1776)". Research, Society and Development 11, n. 5 (9 aprile 2022): e34511528144. http://dx.doi.org/10.33448/rsd-v11i5.28144.
Testo completoAbstract (sommario):
The aim of the present study was to evaluate the mechanical behaviour of the femur and humerus of Cerdocyon thous through three-point bending and axial compression tests. For this, 13 femurs and 15 humerus were used in the bending test, and 14 femurs and 15 humerus in the compression test; after the assays were completed, bone fragments were collected for evaluation by means of conventional optical and polarized light microscopy, and scanning electron microscopy. It was observed that the humerus is more resistant in relation to the femur in both tests, and that bone length and weight, in addition to the width of the diaphysis, are influential on the mechanical behaviour. Microscopic evaluation showed that, on the cranial surface of the fractured bones under flexion, the fracture was caused by the deflection mechanism, while the caudal surface was ruptured by delamination. In bones submitted to axial compression, diaphyseal fractures occurred by deflection, while physeal fractures were caused by several mechanisms. There was no significant correlation between the arrangement of collagen fibres or mineral content on the mechanical properties obtained in both assays. It can be concluded that there are significant differences in the mechanical behaviour of the femur and humerus of C. thous, where the humerus is more resistant than the femur in both flexion and compression loads. Such data allow us to predict the bone mechanical behaviour of C. thous in the face of trauma caused by flexion and compression impacts, such as those resulting from running over.
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Sheta, Abdelrazek. "Anatomical and Histological Evidence of Aluminum Bone Toxicity: An Experimental Study". Journal of Umm Al-Qura University for Medical Sciences 9, n. 1 (22 maggio 2023): 23–29. http://dx.doi.org/10.54940/ms40638052.
Testo completoAbstract (sommario):
Objectives: Aluminum has may be cytotoxic to animals and humans. It is mainly stored in bone and unfortunately, its absorption is increased with age. This study is done to define possible aluminum pathological changes in bone of aging albino rats. Methods: Twenty male albino rats aged 24 months was divided into two groups, control experimental. Experimental group received aluminum chloride for 10 weeks orally. The femur of both control and experimental group is investigated by light and electron microscope. Plain X-ray to the femur as an example to bone is also done. Results: Plain X-ray of femurs of the experimental group showed medullary bone trabeculae destruction, cortical bone resorption and sclerosis. Sections of the shaft of the femur stained with H&E confirmed X-ray gross picture and the bony cortex appeared very thin in comparison with control and showed multiple erosion cavities that may leads to bone fractures. Bone cells appeared few and highly degenerated while the periosteum was very thin and detached from the bone cortex. The bone trabeculae were highly destroyed, and the wide bone marrow spaces were filled by fat cells in some bones. At the level of electron microscope, both osteocytes and osteoblasts revealed severe degenerative changes and showed few irregular collagenous matrices. Conclusion: The degenerative changes observed in the bone of this study are most probably due to aluminum ingestion.
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Papini, M., R. Zdero, E. H. Schemitsch e P. Zalzal. "The Biomechanics of Human Femurs in Axial and Torsional Loading: Comparison of Finite Element Analysis, Human Cadaveric Femurs, and Synthetic Femurs". Journal of Biomechanical Engineering 129, n. 1 (25 giugno 2006): 12–19. http://dx.doi.org/10.1115/1.2401178.
Testo completoAbstract (sommario):
To assess the performance of femoral orthopedic implants, they are often attached to cadaveric femurs, and biomechanical testing is performed. To identify areas of high stress, stress shielding, and to facilitate implant redesign, these tests are often accompanied by finite element (FE) models of the bone/implant system. However, cadaveric bone suffers from wide specimen to specimen variability both in terms of bone geometry and mechanical properties, making it virtually impossible for experimental results to be reproduced. An alternative approach is to utilize synthetic femurs of standardized geometry, having material behavior approximating that of human bone, but with very small specimen to specimen variability. This approach allows for repeatable experimental results and a standard geometry for use in accompanying FE models. While the synthetic bones appear to be of appropriate geometry to simulate bone mechanical behavior, it has not, however, been established what bone quality they most resemble, i.e., osteoporotic or osteopenic versus healthy bone. Furthermore, it is also of interest to determine whether FE models of synthetic bones, with appropriate adjustments in input material properties or geometric size, could be used to simulate the mechanical behavior of a wider range of bone quality and size. To shed light on these questions, the axial and torsional stiffness of cadaveric femurs were compared to those measured on synthetic femurs. A FE model, previously validated by the authors to represent the geometry of a synthetic femur, was then used with a range of input material properties and change in geometric size, to establish whether cadaveric results could be simulated. Axial and torsional stiffnesses and rigidities were measured for 25 human cadaveric femurs (simulating poor bone stock) and three synthetic “third generation composite” femurs (3GCF) (simulating normal healthy bone stock) in the midstance orientation. The measured results were compared, under identical loading conditions, to those predicted by a previously validated three-dimensional finite element model of the 3GCF at a variety of Young’s modulus values. A smaller FE model of the 3GCF was also created to examine the effects of a simple change in bone size. The 3GCF was found to be significantly stiffer (2.3 times in torsional loading, 1.7 times in axial loading) than the presently utilized cadaveric samples. Nevertheless, the FE model was able to successfully simulate both the behavior of the 3GCF, and a wide range of cadaveric bone data scatter by an appropriate adjustment of Young’s modulus or geometric size. The synthetic femur had a significantly higher stiffness than the cadaveric bone samples. The finite element model provided a good estimate of upper and lower bounds for the axial and torsional stiffness of human femurs because it was effective at reproducing the geometric properties of a femur. Cadaveric bone experiments can be used to calibrate FE models’ input material properties so that bones of varying quality can be simulated.
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GRANDHI, R. R., A. B. THORNTON-TRUMP e C. E. DOIGE. "INFLUENCE OF DIETARY CALCIUM-PHOSPHORUS LEVELS ON CERTAIN MECHANICAL, PHYSICAL AND HISTOLOGICAL PROPERTIES AND CHEMICAL COMPOSITION OF BONES IN GILTS AND SECOND LITTER SOWS". Canadian Journal of Animal Science 66, n. 2 (1 giugno 1986): 495–503. http://dx.doi.org/10.4141/cjas86-051.
Testo completoAbstract (sommario):
A 24 factorial design of treatments involving two breeds (Lacombe (L) and Yorkshire (Y)) and two dietary calcium-phosphorus (Ca-P) levels (100% or 150% of 1979 National Academy of Sciences-National Research Council recommended Ca-P levels) during finishing, gestation and lactation periods, was used to study the changes in certain mechanical, physical, chemical and histological characteristics of bones in gilts and second litter sows. Femur, 3rd metacarpal and 6th rib bones were collected from the right half of the 32 (16L + 16Y) gilts slaughtered at 159 ± 1 d of age and 46 (22L + 24Y) second litter sows slaughtered at the end of second gestation-lactation cycle. The mechanical properties, breaking force, bending moment, breaking stress and elastic modulus of femur and 3rd metacarpal bones, determined by flexture tests using an Instron Universal Testing Machine, were not significantly (P > 0.05) influenced by the dietary Ca-P levels in gilts or sows. Feeding 150% of NRC Ca-P levels during the finishing period increased (P < 0.05) the bone shaft diameter (23.2 ± 0.2 vs.22.3 ± 0.2 mm) in femurs and percent bone ash (60.5 ± 0.4 vs. 59.0 ± 0.4) and percent bone Ca (19.0 ± 0.5 vs. 17.0 ± 0.5) in 3rd metacarpals of gilts. The femurs and 3rd metacarpals of L gilts and sows had generally larger shaft diameters but lower bone strength, elastic modulus and bone cortex thickness than in Y pigs. The histological examination revealed no abnormalities in trabecular and cartilage structures of 6th ribs between sows fed different Ca-P levels. The results suggested that feeding 150% of NAS-NRC Ca-P levels during finishing, gestation and lactation periods produced some positive changes in bone characteristics of gilts and second litter sows with no identifiable changes in their ability to function. Certain bone characteristics were different between the two breeds and their response to dietary Ca-P levels varied between femur and 3rd metacarpals of gilts and sows. Key words: Calcium, phosphorus, bone characteristics, gilts, sows
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Ching, Michael, Aaron Gee, Christopher Del Balso, Abdel Lawendy, Emil H. Schemitsch, Radovan Zdero e David Sanders. "Biomechanical Consequences of Nail Insertion Point and Anterior Cortical Perforation for Antegrade Femoral Nailing". BioMed Research International 2020 (18 dicembre 2020): 1–10. http://dx.doi.org/10.1155/2020/5878607.
Testo completoAbstract (sommario):
This biomechanical study assessed the influence of changing antegrade cephalomedullary nail insertion point from anterior to neutral to posterior locations relative to the tip of the greater trochanter with or without anterior cortical perforation in the distal femur. Artificial osteoporotic femurs and cephalomedullary nails were used to create 5 test groups each with 8 specimens: intact femur without a nail or perforation, anterior nail insertion point without perforation, neutral nail insertion point without perforation, posterior nail insertion point without perforation, and posterior nail insertion point with perforation. Nondestructive biomechanical tests were done at 250 N in axial, coronal 3-point bending, sagittal 3-point bending, and torsional loading in order to measure overall stiffness and bone stress. The intact femur group vs. all femur/nail groups had lower stiffness in all loading modes ( p ≤ 0.018 ), as well as higher bone stress in the proximal femur ( p ≤ 0.027 ) but not in the distal femur above the perforation ( p = 0.096 ). Compared to each other, femur/nail groups only showed differences in sagittal 3-point bending stiffness for anterior and neutral vs. posterior nail insertion points without ( p ≤ 0.025 ) and with perforation ( p ≤ 0.047 ). Although it did not achieve statistical significance ( p ≥ 0.096 ), moving the nail insertion point from anterior to neutral to posterior to posterior with perforation did gradually increase bone stress by 45% (proximal femur) and 46% (distal femur). No femur or hardware failures occurred. Moving the nail insertion point and the presence of a perforation had little effect on stiffness, but the increased bone stress may be important as a predictor of fracture. Based on current bone stress results, surgeons should use anterior or neutral nail insertion points to reduce the risk of anterior cortical perforation.
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Parmar, Ajay, Pankaj Maheria e Kanan Shah. "Study of Nutrient Foramina in Human Typical Long Bones of Lower Limb". National Journal of Clinical Anatomy 08, n. 02 (aprile 2019): 077–81. http://dx.doi.org/10.1055/s-0039-1688547.
Testo completoAbstract (sommario):
Abstract Background and Aim Nutrient foramina form important landmarks on human bones as they form portal of entry for nutrient artery. Nutrient artery is an important source of blood supply for a growing bone. Different parameters of nutrient foramina are important in various procedures such as vascularized bone grafting, tumor resections, fracture repair, and other surgical procedures in orthopedics. The objective of the present study was to report the number, position, direction, size, and foraminal index of nutrient foramen in the femur, tibia, and fibula. Materials and Methods The present study analyzed the location, direction, size, and the number of nutrient foramina in the diaphysis of 180 long bones of the lower limbs of adults: 60 femurs, 60 tibiae, and 60 fibulae. Result The location of the nutrient foramina is predominant on the posterior aspect of the lower limb long bones. Single nutrient foramen found in the tibia (100%), femur (48.3%), and fibula (60%) may represent as a single source of blood supply. The majority of the femur (50%) and few fibulae (5%) had a double nutrient foramen. The mean foraminal index for the lower limb bones was 40.5% for the left and 38.2% for the right side of the femur, 31.69% for the left and 32.3% for the right side of the tibia, and 32.7% for the left and 31.7% for the right side of the fibula. Conclusion The present study provides information on the number, size, position, and direction of nutrient foramina of the femur, tibia, and fibula bones.
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Wysocki, Matthew A., e Scott T. Doyle. "Advancing Osteoporosis Evaluation Procedures: Detailed Computational Analysis of Regional Structural Vulnerabilities in Osteoporotic Bone". Journal of Personalized Medicine 13, n. 2 (13 febbraio 2023): 321. http://dx.doi.org/10.3390/jpm13020321.
Testo completoAbstract (sommario):
Osteoporotic fractures of the femur are associated with poor healing, disability, reduced quality of life, and high mortality rates within 1 year. Moreover, osteoporotic fractures of the femur are still considered to be an unsolved problem in orthopedic surgery. In order to more effectively identify osteoporosis-related fracture risk and develop advanced treatment approaches for femur fractures, it is necessary to acquire a greater understanding of how osteoporosis alters the diaphyseal structure and biomechanical characteristics. The current investigation uses computational analyses to comprehensively examine how femur structure and its associated properties differ between healthy and osteoporotic bones. The results indicate statistically significant differences in multiple geometric properties between healthy femurs and osteoporotic femurs. Additionally, localized disparities in the geometric properties are evident. Overall, this approach will be beneficial in the development of new diagnostic procedures for highly detailed patient-specific detection of fracture risk, for establishing novel injury prevention treatments, and for informing advanced surgical solutions.
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Plánka, Ladislav, David Starý, Jana Hlučilová, Jiří Klíma, Josef Jančář, Leoš Křen, Jana Lorenzová et al. "Comparison of Preventive and Therapeutic Transplantations of Allogeneic Mesenchymal Stem Cells in Healing of the Distal Femoral Growth Plate Cartilage Defects in Miniature Pigs". Acta Veterinaria Brno 78, n. 2 (2009): 293–302. http://dx.doi.org/10.2754/avb200978020293.
Testo completoAbstract (sommario):
The aim of the study was to verify whether there is a difference in the lengthwise growth of the femurs and in their angular deformity when comparing preventive vs. therapeutic transplantation of allogeneic mesenchymal stem cells (MSCs) to an iatrogenic defect in the distal physis of femur. Modified composite chitosan/collagen type I scaffold with MSCs was transplanted to an iatrogenically created defect of the growth cartilage in the lateral condyle of the left femur in 20 miniature male pigs. In Group A of animals (n = 10) allogeneic MSCs were transplanted immediately after creating the defect in the distal physis of femur (preventive transplantation). In Group B of animals (n = 10) the same defect of the growth cartilage was treated by transplantation of allogeneic MSCs four weeks after its creation (therapeutic transplantation), after the excision of the bone bridge that had formed in it. On average, left femurs with a damaged distal physis and preventively transplanted allogeneic MSCs (Group A) grew during 4 months from transplantation by 0.56 ± 0.44 cm more than right femurs without the transplantation of MSCs, whereas left femurs with physeal defects treated with a therapeutic transplantation of allogeneic MSCs (Group B) by 0.14 ± 0.72 cm only, compared to right femurs without transplanted MSCs. Four months after preventive transplantation of MSCs (Group A), valgus deformity of the distal part of left femur with the defect was 0.78 ± 0.82°; in the control group (right femur in the same animal without MSCs transplantation) it was 3.7 ± 0.82°. After therapeutic transplantation of MSCs (Group B) 0.6 ± 3.4°, in the control group (right femur in the same animal without MSCs transplantation) it was 2.1 ± 2.9°. In all the animals of Groups A and B, the presence of newly formed hyaline cartilage was confirmed histologically and immunohistochemically. In the distal physis of right femurs with an iatrogenic defect of the growth cartilage without the transplantation of MSCs (control) bone bridge was formed. Preventive transplantation of allogeneic MSCs into the defect of the distal growth zone of femur appears more suitable compared to the therapeutic transplantation, with regard to the more pronounced lengthwise bone growth. Differences found in the extent of valgus deformity were non-significant comparing preventive and therapeutic transplantations of MSCs.
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Dervisevic, Lejla, Amela Dervisevic, Zurifa Ajanovic e Ilvana Hasanbegovic. "Analytical and morphometric study of nutrient foramina of femur and its clinical implications". International Journal of Research in Medical Sciences 7, n. 4 (27 marzo 2019): 1324. http://dx.doi.org/10.18203/2320-6012.ijrms20191347.
Testo completoAbstract (sommario):
Background: The femur is supplied princially by the diaphyseal nutrient artery which enters the bone throught the nutrient foramen. This supply is essential during the growing period, the early phases of ossification, and in different surgical procedures. The aim of present study was to examine the morphology and topography of the femur nutrient foramen to provide detalied data on such features.Methods: This was a cross-sectional-descriptive study in which we observed 50 femurs. We analysed the number and location of nutrient foramina, the length of the bone, the position of the nutrient foramen regarding to values of FI, correlation between number of nutrient foramen and length of femur, correlation between position of nutrient foramen and side of extremity to which femur belongs.Results: The double foramina were common in right (57.1%) and left (42.1%) femur, mostly located in medial lip of aspera line in right (64.3%) and on the lateral lip in left femur (68.4%), with statistically significant correlation, χ = 4.85; p = 0.03, p <0.05. The foramina in left (89.5%) and right (96.4%) femur were commonly observed at their middle third, with no statistically significant correlation between position of foramen accordingly to Foraminal Index value and side of extremity on which femur belongs (p=0.56; p>0.05). There is positive correlation between length of right and left femur and number of foramina.Conclusions: The study provides data of the nutrient foramina on femur, which is helpful for clinicians to help preserve bone vascularization during surgery.
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Myszka, Anna, Hanna Mańkowska-Pliszka, Ewa Rzeźnicka, Agnieszka Dąbkowska e Jacek Tomczyk. "Case study of Legg-Calvé-Perthes disease observed in Radom (Poland, 18th–19th century) with literature review". Anthropological Review 86, n. 1 (28 marzo 2023): 23–36. http://dx.doi.org/10.18778/1898-6773.86.1.03.
Testo completoAbstract (sommario):
The aim of this study is to present the pathological lesions observed in a skeleton (male, about 35–38 years old) from Radom (Poland), dated to the 18th–19th century. Bone changes were observed in both femurs and both pelvic bones. The head of the femur is enlarged and deformed, described as “mushroom-shaped”, with areas of smooth cortex and cavities, or possible cystic residues. The neck of femur is short and thick. The bone shaft and distal epiphysis do not show any changes. The changes were also observed in both acetabularies of the hip joint (marginal bone formation, subchondral bone remodelling). Radiographic images show bilateral necrosis of the femoral head. There is a significant sclerotization of the femoral head, with a discrete visible crescent sign. These macroscopic and radiological changes match the symptoms associated with Legg-Calvé-Perthes disease. This is the first case of the disease described in bioarchaeological materials from Poland.
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Mutluay, Sukriye Deniz, Ahmet Kursad Acıkgoz e Memduha Gulhal Bozkır. "Evaluation of Nutrient Foramen in Adult Dry Human Femur". Journal of Evolution of Medical and Dental Sciences 10, n. 41 (11 ottobre 2021): 3566–70. http://dx.doi.org/10.14260/jemds/2021/723.
Testo completoAbstract (sommario):
BACKGROUND Nutrient foramen is a large opening that transfers the arteries that supply the bone to the bone cavity. During surgical procedures, it is very important to have precise and complete information about the location of the foramina to determine whether the fracture line passes close to the nutrient foramina. The purpose of this study was to determine the number and position of the femoral nutrient foramina together with morphometric measurements. METHODS A total of 93 dry adult femurs with unknown sexes were examined in this study. The direction, location and the total number of nutrient foramina of the femur were investigated by using an anthropometer (Lafayette instrument, Indiana). Also, foraminal index was calculated. RESULTS The analysis revealed that 28 (53.8 %) of the femurs with a single nutrient foramen were on the right side and 22 (53.7 %) were on the left side, respectively. Femurs with double nutrient foramina were 23 (44.2 %) and 18 (43.9 %) on right and left sides, respectively. Femurs with triple nutrient foramina were 1(1.9 %) and 1 (2.4 %) on right and left sides, respectively. The foraminal index of femurs was found as (41, 58 %) and (42, 23 %) on the right and left sides, respectively. The nutrient foramen was mostly 84 (90.3 %) located at the middle third of the femur. CONCLUSIONS The findings of this study provide information and details about nutrient foramen which have clinical importance, especially in surgical procedures like bone grafting and microsurgical vascularized bone transplantation. KEY WORDS Femur, Foraminal Index, Nutrient Artery, Nutrient Foramina
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McGee, Michael, J. V. D. Hough e Mark W. Wood. "Homograft Microlathed Femur Prosthesis in Stapedectomy". Ear, Nose & Throat Journal 81, n. 3 (marzo 2002): 169–71. http://dx.doi.org/10.1177/014556130208100312.
Testo completoAbstract (sommario):
The use of homografts in ossiculoplasty has been well documented in the literature. In the early 1980s, nonossicular homograft otic capsule bone was used as a prosthetic material in stapedectomy. We began using homograft femur as a prosthetic material in the early 1990s. In this article, we report the results of a retrospective study of the use of homograft femur prostheses. A series of 300 stapedectomies was performed between Aug. 24, 1992, and Jan. 20, 2000. Total footplate removal with preservation of the posterior crus was our procedure of choice. However, in 116 of these cases, the posterior crus could not be used, and a homograft femur prosthesis was substituted. For these prostheses, all homograft femurs were obtained from the American Red Cross. All prostheses were prepared in the bone laboratory and stored in the bone bank until needed. After an adequate period of follow-up, we tabulated our results. We found that in 89 of 113 cases (78.8%) available for follow-up, the air-bone gap was completely closed. In addition, the air-bone gap was closed to within 5 dB in 11 patients (9.7%) and closed to within 10 dB in five patients (4.4%). In all, 105 of the 113 homograft femur prosthetic procedures (92.9%) resulted in a successful outcome.
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Yakin, Khusnul. "SIMULATION OF THE MECHANICAL STIMULATION EFFECT ON THE PEN JUNCTION BETWEEN BONE AND PELVIC BASED ON FINITE ELEMENT METHODS". Jurnal Neutrino 12, n. 2 (30 giugno 2020): 65–70. http://dx.doi.org/10.18860/neu.v12i2.9243.
Testo completoAbstract (sommario):
Bone remodeling process influenced by cells osteoblast and osteoclast. The remodeling of cortical and trabecular influenced by mechanical stimuli. In this study, cortical and trabecular bones of 25 years old humans were observed, and the result was the cortical bone has the average Young’s modulo 17.9 MPa with the Poisson’s ratio of 0.4. Trabecular bone has the average Young’s modulo of 13 MPa and the Poisson’s ratio of 0.5. The metal orthopedic bone screw, which has used in this research simulation, was is a Titanium screw. The screw has Young’s modulo of 110 GPa and the Poisson’s ratio of 0.29. The results of the simulation of femoral bone elasticity limit with standing activity at the age of 25 were found in the left femur of 112.9416 MPa and the right femur of 115.5134 MPa. The limit of elasticity of the femur due to walking was found in the left femur of 115.2166 MPa with an accuracy of 94.11% and the right femur of 117.6692 MPa.
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Hryhorieva, P. V. "Morphometric Characteristics of the Thigh Bone in Human Fetuses". Ukraïnsʹkij žurnal medicini, bìologìï ta sportu 6, n. 4 (18 settembre 2021): 38–43. http://dx.doi.org/10.26693/jmbs06.04.038.
Testo completoAbstract (sommario):
Defining quantitative growth parameters of individual skeletal bones, namely the right and left femurs, is practically important for determining the age of the fetus. Lack of data on changes in the length of the femur in 4-10 months’ fetuses, as well as the dependence of its morphometric parameters on the length of the lower limb and the age of the fetus, prompted us to conduct this study. The purpose of the study was to determine the morphometric parameters of the length of the right and left femurs during the fetal period of human ontogenesis, which could form the base of normal indicators. Materials and methods. Morphometric study was performed on the lower extremities specimens of 40 human fetuses of an 81.0-375.0 mm parietal-coccygeal length. Results and discussion. As a result of the study, the dynamics of changes in the length of the right and left femurs and lower extremities in 4-10 months’ human fetuses was established. Direct correlations were found in the studied fetal groups, and only in 5-month-old fetuses a direct medium-strength reliable correlation between the lengths of the right and left femurs was found. A weak correlation between the length of the left lower limb and the length of the left femur was found in 7-month-old fetuses. In other cases, direct significant strong correlations were found between the analyzed indicators. The results obtained regarding the change in the length of the right and left femurs, as well as the Pearson correlation coefficient between the morphometric parameters of the length of the right and left femurs and the length of the lower extremities and parietal-coccygeal length of human fetuses 4-10 months are important both theoretically and practically for fetal anatomy. Conclusion. During the fetal period of human ontogenesis, where there is a relatively uniform increase in the length of the right and left femurs, no significant differences in their length were detected. Between the 4th and the 10th month of fetal development, the length of the right femur increases by 5.59 times (from 13.18 ± 2.56 mm to 73.66 ± 2.19 mm), and the length of the left femur increases by 5.44 times: from 13.54 ± 2.35 mm to 73.73 ± 2.12 mm, respectively. In the fetal period the right and left lower extremities also grow equally, no significant differences in their length have been established
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Watanabe, Ryota, Aira Matsugaki, Takuya Ishimoto, Ryosuke Ozasa, Takuya Matsumoto e Takayoshi Nakano. "A Novel Ex Vivo Bone Culture Model for Regulation of Collagen/Apatite Preferential Orientation by Mechanical Loading". International Journal of Molecular Sciences 23, n. 13 (4 luglio 2022): 7423. http://dx.doi.org/10.3390/ijms23137423.
Testo completoAbstract (sommario):
The anisotropic microstructure of bone, composed of collagen fibers and biological apatite crystallites, is an important determinant of its mechanical properties. Recent studies have revealed that the preferential orientation of collagen/apatite composites is closely related to the direction and magnitude of in vivo principal stress. However, the mechanism of alteration in the collagen/apatite microstructure to adapt to the mechanical environment remains unclear. In this study, we established a novel ex vivo bone culture system using embryonic mouse femurs, which enabled artificial control of the mechanical environment. The mineralized femur length significantly increased following cultivation; uniaxial mechanical loading promoted chondrocyte hypertrophy in the growth plates of embryonic mouse femurs. Compressive mechanical loading using the ex vivo bone culture system induced a higher anisotropic microstructure than that observed in the unloaded femur. Osteocytes in the anisotropic bone microstructure were elongated and aligned along the long axis of the femur, which corresponded to the principal loading direction. The ex vivo uniaxial mechanical loading successfully induced the formation of an oriented collagen/apatite microstructure via osteocyte mechano-sensation in a manner quite similar to the in vivo environment.
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Mathukumar, S., VA Nagarajan e A. Radhakrishnan. "Analysis and validation of femur bone data using finite element method under static load condition". Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 233, n. 16 (11 giugno 2019): 5547–55. http://dx.doi.org/10.1177/0954406219856028.
Testo completoAbstract (sommario):
Humans face bone fracture when they unfortunately met an accident, which requires timely medical attention for healing and repairing the fractured bone; otherwise that paralyzes their life. 3D modeling technique with computational method is very helpful at the side of doctors for healing and repairing the damaged bones. Fractional bone healing is one of the natural processes, which regain the mechanical reliability of the bone to a limited level of failures. The relationship between the biology and mechanics has introduced a new branch namely biomechanics. Various biomechanics models were used to identify the fracture for different patients and helps in the fracture treatment. The aim of this work is to find out the high stress concentration area of the femur bone, which has been extracted as image from computer tomography scanner. The retrieved noise-free femur bone image is tested by the static load condition with the help of the finite element analysis. The result obtained from the testing of different loads has been compared with the existing literature. It is found that the femur bone has tensile and compressive stress, and the neck area of the femur is at a very high stress concentration. The outcome of this work is much supportive to orthopedic surgeons in femur surgery and bone prosthesis by avoiding experiments on femur bone.
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Kim, Jong Heon, Mitsuo Niinomi e Toshikazu Akahori. "Influence of Bone Structure on Mechanical Properties of Bovine and Swine Compact Bones". Materials Science Forum 475-479 (gennaio 2005): 2407–10. http://dx.doi.org/10.4028/www.scientific.net/msf.475-479.2407.
Testo completoAbstract (sommario):
Recently, more attention has been focused on the research and development of biomaterials such as an artificial bone because of the rapid-increasing demand for biomaterials from the aging society in the world. However, the study on the bone itself is not enough. In particular, there is little information about the fracture toughness, and fatigue property of bones, and effect of the microstructure on the fracture characteristic. In this study, the fracture toughness of the bovine and swine humerus and femur as well as the fatigue property of the bovine humerus and femur was investigated with relating microstructures. The fracture toughness of plexiform bone is greater than that of haversian bone, and the fatigue strength of the plexiform bone taken from the humerus and femur is a little greater than that of the haversian bone taken from the humerus and femur in particular in high cycle fatigue life regions.
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Rauf, Abdul, e Syed Ismail Ahmad. "Study of Mechanical Energy Dissipation by Normal and Decalcified Animals Bones". Biosciences, Biotechnology Research Asia 16, n. 1 (28 marzo 2019): 113–19. http://dx.doi.org/10.13005/bbra/2728.
Testo completoAbstract (sommario):
The energy dissipated properties of normal and decalcified femur, rib and scapula bones of animals ox and camel have been studied by uniform bending technique. A hysteresis curve has been observed between the elevation in bone and load applied. It is observed that the energy dissipated as calculated from the hysteresis loop for rib is more than that of femur and scapula of ox and camel. It has been observed that the dissipation of energy in normal bone is less than that of decalcified bone under the same condition of applied load. The highest energy dissipation was observed in case of rib bone of camel compared to that of any other bone, rib of camel and scapula of ox dissipates maximum energy than femur bones. The study suggests that this technique is simple, elegant and inexpensive besides accurate in determining viscoelastic properties of bone.
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Chen, Y., L. Huang, J. Zhu e K. Wu. "Effects of short-term glucocorticoid administration on bone mineral density, biomechanics and microstructure in rats’ femur". Human & Experimental Toxicology 36, n. 3 (11 luglio 2016): 287–94. http://dx.doi.org/10.1177/0960327116649674.
Testo completoAbstract (sommario):
The effects of short-term use of oral glucocorticoid (GC) on the skeleton are not well defined. To address this gap, the influences of 7 days, 21 days of GC administration on femurs of intact rats were investigated. Forty 4-month-old female Sprague–Dawley rats were randomly divided into control group (Cont) and prednisone-treated group (Pre) and administered either distilled water or prednisone acetate at doses of 3.5 mg/kg/day for 0, 7 and 21 days, respectively. All the femurs were harvested for dual-energy X-ray absorptiometry scan, biomechanical testing and micro computed tomography scan. The whole body weight, femur bone mineral density (BMD), all three-point bending test parameters, microstructural parameters increased or improved significantly in Cont at day 21 when compared to day 0. The whole body weight, distal femur BMD, Young’s modulus, bending stiffness, density of tissue volume and trabecular thickness (Tb.Th) decreased, while structure model index and trabecular separation (Tb.Sp) increased significantly in Pre at day 21 when compared to age-matched control but had no significant differences between day 7 and day 21. Our data demonstrate that 7-day use of prednisone does not influence on rats’ femur, and 21-day use of prednisone slows in rate of whole body weight gain, decreases femur metaphysis BMD and bone stiffness which mainly due to the deteriorated bone microstructure.
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Taylor, M., e E. W. Abel. "Finite Element Analysis of Poor Distal Contact of the Femoral Component of a Cementless Hip Endoprosthesis". Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 207, n. 4 (dicembre 1993): 255–61. http://dx.doi.org/10.1243/pime_proc_1993_207_304_02.
Testo completoAbstract (sommario):
The difficulty of achieving good distal contact between a cementless hip endoprosthesis and the femur is well established. This finite element study investigates the effect on the stress distribution within the femur due to varying lengths of distal gap. Three-dimensional anatomical models of two different sized femurs were generated, based upon computer tomograph scans of two cadaveric specimens. A further six models were derived from each original model, with distal gaps varying from 10 to 60 mm in length. The resulting stress distributions within these were compared to the uniform contact models. The extent to which femoral geometry was an influencing factor on the stress distribution within the bone was also studied. Lack of distal contact with the prosthesis was found not to affect the proximal stress distribution within the femur, for distal gap lengths of up to 60 mm. In the region of no distal contact, the stress within the femur was at normal physiological levels associated with the applied loading and boundary conditions. The femoral geometry was found to have little influence on the stress distribution within the cortical bone. Although localized variations were noted, both femurs exhibited the same general stress distribution pattern.
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Wang, Lan, Jie Zhang, Wen Zhang, Hui-Lin Yang e Zong-Ping Luo. "Analysis of the Osteogenic Effects of Biomaterials Using Numerical Simulation". BioMed Research International 2017 (2017): 1–7. http://dx.doi.org/10.1155/2017/6981586.
Testo completoAbstract (sommario):
We describe the development of an optimization algorithm for determining the effects of different properties of implanted biomaterials on bone growth, based on the finite element method and bone self-optimization theory. The rate of osteogenesis and the bone density distribution of the implanted biomaterials were quantitatively analyzed. Using the proposed algorithm, a femur with implanted biodegradable biomaterials was simulated, and the osteogenic effects of different materials were measured. Simulation experiments mainly considered variations in the elastic modulus (20–3000 MPa) and degradation period (10, 20, and 30 days) for the implanted biodegradable biomaterials. Based on our algorithm, the osteogenic effects of the materials were optimal when the elastic modulus was 1000 MPa and the degradation period was 20 days. The simulation results for the metaphyseal bone of the left femur were compared with micro-CT images from rats with defective femurs, which demonstrated the effectiveness of the algorithm. The proposed method was effective for optimization of the bone structure and is expected to have applications in matching appropriate bones and biomaterials. These results provide important insights into the development of implanted biomaterials for both clinical medicine and materials science.
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Arpad, Solyom, Cristian Trambitas, Ecaterina Matei, Eugeniu Vasile, Fodor Pal, Iulian Vasile Antoniac, Stefan Ioan Voicu, Tiberiu Bataga e Raluca Fodor. "Effect of Osteoplasty with Bioactive Glass (S53P4) in Bone Healing - In vivo Experiment on Common European Rabbits (Oryctolagus cuniculus)". Revista de Chimie 69, n. 2 (15 marzo 2018): 429–33. http://dx.doi.org/10.37358/rc.18.2.6121.
Testo completoAbstract (sommario):
Osteoplasty, is a procedure mostly applied in complicated bone fractures. Nowadays this method is widely used in primary fracture treatment while the native bone graft is progressively replaced with various synthetic bone substitutes. From the numerous bone grafts we�d like to mention a representative of ceramics, the S53P4 bioactive glass. (BonAlive�). The aim of this study was to investigate the healing process of different fracture types generated on rabbit femurs. During this experiment we used seven common European rabbits. We separated these animals into two groups; in the first group we surgically generated a total fracture in the middle 1/3 of the femur, while in the second group, we produced only a bone defect on the femur. The osteoplasty was carried out with bioactive glass and autologous bone grafts. The radiographic follow-up was immediate after the operation and after 3, 6 and 7 weeks. The animals were euthanized after 19, 20 and 21 weeks, for histomorphometric examination of the femur. It was also studied the ionic release from the used bioactive glass at physiological pH and the etching of the glass was studied by Scanning Electron Microscopy.
30
Chen, Jing, Xiao Na Li, Shi En Tan e Wei Yi Chen. "The Mechanical Strength of Rabbit Femurs Fixed with Calcium Phosphate Cement after Fracture". Advanced Materials Research 343-344 (settembre 2011): 1160–62. http://dx.doi.org/10.4028/www.scientific.net/amr.343-344.1160.
Testo completoAbstract (sommario):
In this study, we invesgated the mechanical properties of the rabbit femurs fixed with calcium phosphate cement (CPC). Twenty adult rabbits were randomly divided into the control group and the group treated with femur fracture artifically, then fixed with CPC. Two weeks after surgery, all rabbits were sacrificed, and femurs were removed for the three point bending test to examine the changes of mechanical parameters of the femurs. Our results showed that although the maximum tension stress of the femurs in the treatment group was smaller than the control, its crosss-sectional area became bigger, which improved the ablity of the femur to bear more loading with the maximum pressure and absorbed energy during destroy up to 83.5% and 64.3% of normal bone material strength. It indicated that it was practicable to fix the fractured femur with CPC from the biomechanical view piont.
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Manjiri, Ganjewar, Shroff Gautam e Mandhana Vaishali. "Multivariate Analysis of Human Adult Femur Length by Various Parameters of Neck of Femur". International Journal of Current Research and Review 14, n. 13 (2022): 71–76. http://dx.doi.org/10.31782/ijcrr.2022.141312.
Testo completoAbstract (sommario):
Introduction: Bones forms the main framework of the human body. Bone structure is different in different individuals depending upon race, sex, height, work, nutrition and geographical area. Femur is the bone which is the longest and strongest in human body and shows highest correlation with stature. Aims: This study has been done to determine the relationship of neck measurements with femur length in Maharashtrian population. Methodology: In the present Study, 54 human femur bones were studied for the following parameters using standard procedures. We took femur length (FL), neck length (NL), neck diameter at narrowest site (NDN) and neck diameter at widest site (NDW) in mms. Results: The data was analysed through SPSS software. The descriptive statistics was analysed. Univariate and Multivariate Regression equations were derived to estimate Femur Length from various neck parameters. In univariate analysis, FL was 344.06 + 2.856 NL with R value 0.513 and in multivariate analysis, FL was 209.457+ 0.89 NL + 10.85 NDN -2.98 NDW with R value 0.867. Conclusion: It has been concluded that femur neck length has a positive correlation with total length of femur and femur length can be calculated if measurements of one or more neck parameters are available.
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Dinsdale, E. C., J. Kaludjerovic e W. E. Ward. "Isoflavone exposure throughout suckling results in improved adult bone health in mice". Journal of Developmental Origins of Health and Disease 3, n. 4 (6 marzo 2012): 271–75. http://dx.doi.org/10.1017/s2040174412000116.
Testo completoAbstract (sommario):
Exposure to isoflavones (ISO), abundant in soy protein infant formula, for the first 5 days of life results in higher bone mineral density (BMD), greater trabecular connectivity and higher peak load of lumbar vertebrae (LV) at adulthood. The effect of lengthening the duration of exposure to ISO on bone development has not been studied. This study determined if providing ISO for the first 21 days of life, which more closely mimics the duration that infants are fed soy protein formula, results in higher BMD, improved bone structure and greater strength in femurs and LV than a 5-day protocol. Female CD-1 mice were randomized to subcutaneous injections of ISO (7 mg/kg body weight/day) or corn oil from postnatal day 1 to 21. BMD, structure and strength were measured at the femur and LV at 4 months of age, representing young adulthood. At the LV, exposure to ISO resulted in higher (P < 0.05) BMD, trabecular connectivity and peak load compared with control (CON). Exposure to ISO also resulted in higher (P < 0.05) whole femur BMD, higher (P < 0.05) bone volume/total volume and lower (P < 0.05) trabecular separation at the femur neck, as well as greater (P < 0.05) peak load at femur midpoint and femur neck compared with the CON group. Exposure to ISO throughout suckling has favorable effects on LV outcomes, and, unlike previous studies using 5-day exposure to ISO, femur outcomes are also improved. Duration of exposure should be considered when using the CD-1 mouse to model the effect of early life exposure of infants to ISO.
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Levadnyi, Ievgen, Jan Awrejcewicz, Yan Zhang e Yaodong Gu. "Comparison of femur strain under different loading scenarios: Experimental testing". Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 235, n. 1 (18 agosto 2020): 17–27. http://dx.doi.org/10.1177/0954411920951033.
Testo completoAbstract (sommario):
Bone fracture, formation and adaptation are related to mechanical strains in bone. Assessing bone stiffness and strain distribution under different loading conditions may help predict diseases and improve surgical results by determining the best conditions for long-term functioning of bone-implant systems. In this study, an experimentally wide range of loading conditions (56) was used to cover the directional range spanned by the hip joint force. Loads for different stance configurations were applied to composite femurs and assessed in a material testing machine. The experimental analysis provides a better understanding of the influence of the bone inclination angle in the frontal and sagittal planes on strain distribution and stiffness. The results show that the surface strain magnitude and stiffness vary significantly under different loading conditions. For the axial compression, maximal bending is observed at the mid-shaft, and bone stiffness is also maximal. The increased inclination leads to decreased stiffness and increased magnitude of maximum strain at the distal end of the femur. For comparative analysis of results, a three-dimensional, finite element model of the femur was used. To validate the finite element model, strain gauges and digital image correlation system were employed. During validation of the model, regression analysis indicated robust agreement between the measured and predicted strains, with high correlation coefficient and low root-mean-square error of the estimate. The results of stiffnesses obtained from multi-loading conditions experiments were qualitatively compared with results obtained from a finite element analysis of the validated model of femur with the same multi-loading conditions. When the obtained numerical results are qualitatively compared with experimental ones, similarities can be noted. The developed finite element model of femur may be used as a promising tool to estimate proximal femur strength and identify the best conditions for long-term functioning of the bone-implant system in future study.
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Abdullah, Abdul Halim, Alias Mohd Saman, Mohd Asri Mohd Nor, Ishkrizat Taib e Giha Tardan. "Effects of Prosthesis Stem Materials on Stress Distribution of Total Hip Replacement". Advanced Materials Research 129-131 (agosto 2010): 343–47. http://dx.doi.org/10.4028/www.scientific.net/amr.129-131.343.
Testo completoAbstract (sommario):
Bone loss and bone thickening phenomenon occurred due to different stiffness of the implant and femur. Implant with stiffer materials than the bone carries majority of the load and it transferred down along the implant till the distal tip of the stem. Both phenomenons contribute to stress shielding and loosening of the prosthesis stem. In this study, the stress distributions in intact femur and THR femur are established using finite element method. The THR femur model consists of cemented hip Ti6Al4V and CoCrMo prosthesis stem implanted inside the femur bone. Effects of different material properties of the prosthesis stem on the resulting stress distributions are investigated. Results shows that the largest discrepancy in stress values between intact and THR femur is predicted along the middle region at both lateral and medial planes. The distal region shows that the calculated stress for both THR femur experienced higher stress magnitude than that of intact femur. The higher stress in THR femur leads to bone thickening at the particular region. The corresponding stress magnitude saturates at 25 MPa for THR femur while intact femur is slightly lower at 22 MPa.
35
Nuțu, Emil, e Mihai Tarcolea. "Simulation of Bone Mechanical Adaptation in a 3D Model of the Proximal Femur Using the Stanford Strain Energy Density Approach". Key Engineering Materials 638 (marzo 2015): 171–76. http://dx.doi.org/10.4028/www.scientific.net/kem.638.171.
Testo completoAbstract (sommario):
The mathematical theories of bone mechanical adaptation are based on a nonlinear ordinary differential equation which governs the evolution of bone density with respect to the applied loads. If the density distribution achieved within a certain bone model resembles the expected distribution observed in the real bone, then the mathematical theory is usually thought to be suited for such simulations. As test problem, it was extensively used the coronal section of the proximal femur. This section inspired the very creation of the mathematical models following Wolff’s observations regarding trabecular architecture. However, the lack of quantitative data when using the bi dimensional femur model prevents the quantitative validation of the adaptation mathematical models. Using computed tomography is now possible to reconstruct the three dimensional geometry of bones and also to estimate the apparent density based on correlations with the Hounsfield units. This method was already used to quantitatively validate the simulation of bone remodeling into different bones and proved to be efficient. The paper presents the apparent density distributions achieved into the 3D model of the proximal femur by coupling the finite element method with the Stanford bone adaptation equation. The densities obtained in this manner are compared by those determined from the tomographic data of the same bone. The purpose relies on establishing whether the three dimensional end proximity of the femur bone can be used for quantitative validation of remodeling simulations.
36
Garbieri, Thais Francini, Victor Martin, Carlos Ferreira Santos, Pedro de Sousa Gomes e Maria Helena Fernandes. "The Embryonic Chick Femur Organotypic Model as a Tool to Analyze the Angiotensin II Axis on Bone Tissue". Pharmaceuticals 14, n. 5 (16 maggio 2021): 469. http://dx.doi.org/10.3390/ph14050469.
Testo completoAbstract (sommario):
Activation of renin–angiotensin system (RAS) plays a role in bone deterioration associated with bone metabolic disorders, via increased Angiotensin II (AngII) targeting Angiotensin II type 1 receptor/Angiotensin II type 2 receptor (AT1R/AT2R). Despite the wide data availability, the RAS role remains controversial. This study analyzes the feasibility of using the embryonic chick femur organotypic model to address AngII/AT1R/AT2R axis in bone, which is an application not yet considered. Embryonic day-11 femurs were cultured ex vivo for 11 days in three settings: basal conditions, exposure to AngII, and modulation of AngII effects by prior receptor blockade, i.e., AT1R, AT2R, and AT1R + AT2R. Tissue response was evaluated by combining µCT and histological analysis. Basal-cultured femurs expressed components of RAS, namely ACE, AT1R, AT2R, and MasR (qPCR analysis). Bone formation occurred in the diaphyseal region in all conditions. In basal-cultured femurs, AT1R blocking increased Bone Surface/Bone Volume (BS/BV), whereas Bone Volume/Tissue Volume (BV/TV) decreased with AT2R or AT1R + AT2R blockade. Exposure to AngII greatly decreased BV/TV compared to basal conditions. Receptor blockade prior to AngII addition prevented this effect, i.e., AT1R blockade induced BV/TV, whereas blocking AT2R caused lower BV/TV increase but greater BS/BV; AT1R + AT2R blockade also improved BV/TV. Concluding, the embryonic chick femur model was sensitive to three relevant RAS research setups, proving its usefulness to address AngII/AT1R/AT2R axis in bone both in basal and activated conditions.
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Ward, Wendy E., Susie Kim e W. Robert Bruce. "A western-style diet reduces bone mass and biomechanical bone strength to a greater extent in male compared with female rats during development". British Journal of Nutrition 90, n. 3 (settembre 2003): 589–95. http://dx.doi.org/10.1079/bjn2003952.
Testo completoAbstract (sommario):
Evidence from epidemiological and animal-feeding trials suggests that a western-style diet that is high in fat, and low in Ca, vitamin D and folic acid may result in low bone mass and poor bone quality: this leads to an increased risk of fragility fracture. The overall objective of the present study was to determine the effect of feeding a western-style diet (low in Ca (0·4 g/kg diet, Ca:P ratio 1:10), cholecalciferol (3 μg/kg diet), folic acid (0·23 mg/kg diet) and fibre (20 g/kg diet), and high in fat (200 g/kg diet)) for 17 weeks on bone mineral content (BMC) and the biomechanical bone strength of rat femurs. A secondary objective was to determine whether femurs from male and female rats (seven to eight rats per group) respond differently to the western-style diet. Male and female rats weighing 150–180 g were fed a western-style diet or a control diet for 17 weeks. At the end of the feeding trial, femur BMC was measured by ashing, and biomechanical properties were determined by three-point bending. Femur BMC and the majority of biomechanical properties measured were lower (P<0·05) among male and female rats fed a western-style diet compared with a control diet, despite similar weight gain and final body weight within genders. However, the western-style diet had a greater negative effect on femur BMC and biomechanical strength properties among male rats compared with females. This may be because male rats experienced greater overall body growth, as assessed by weight gain, than female rats, and suggests that the nutrient composition of the western-style diet did not support the development of strong femurs.
38
Zdero, R., H. Bougherara, A. Dubov, S. Shah, P. Zalzal, A. Mahfud e E. H. Schemitsch. "The effect of cortex thickness on intact femur biomechanics: A comparison of finite element analysis with synthetic femurs". Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 224, n. 7 (9 dicembre 2009): 831–40. http://dx.doi.org/10.1243/09544119jeim702.
Testo completoAbstract (sommario):
Biomechanical studies on femur fracture fixation with orthopaedic implants are numerous in the literature. However, few studies have compared the mechanical stability of these repair constructs in osteoporotic versus normal bone. The present aim was to examine how changes in cortical wall thickness of intact femurs affect biomechanical characteristics. A three-dimensional, linear, isotropic finite element (FE) model of an intact femur was developed in order to predict the effect of bicortical wall thickness, t, relative to the femur's mid-diaphyseal outer diameter, D, over a cortex thickness ratio range of 0 ≤ t/ D ≤ 1. The FE model was subjected to loads to obtain axial, lateral, and torsional stiffness. Ten commercially available synthetic femurs were then used to mimic ‘osteoporotic’ bone with t/ D = 0.33, while ten synthetic left femurs were used to simulate ‘normal’ bone with t/ D = 0.66. Axial, lateral, and torsional stiffness were measured for all femurs. There was excellent agreement between FE analysis and experimental stiffness data for all loading modes with an aggregate average percentage difference of 8 per cent. The FE results for mechanical stiffness versus cortical thickness ratio (0 ≤ t/ D ≤ 1) demonstrated exponential trends with the following stiffness ranges: axial stiffness (0 to 2343 N/mm), lateral stiffness (0 to 62 N/mm), and torsional stiffness (0 to 198 N/mm). This is the first study to characterize mechanical stiffness over a wide range of cortical thickness values. These results may have some clinical implications with respect to appropriately differentiating between older and younger human long bones from a mechanical standpoint.
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Brien, Earl W., Joseph M. Mirra, Lisa Latanza, Alexander Fedenko e James Luck. "Giant bone island of femur". Skeletal Radiology 24, n. 7 (ottobre 1995): 546–50. http://dx.doi.org/10.1007/bf00202158.
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Vailas, A. C., D. M. Deluna, L. L. Lewis, S. L. Curwin, R. R. Roy e E. K. Alford. "Adaptation of bone and tendon to prolonged hindlimb suspension in rats". Journal of Applied Physiology 65, n. 1 (1 luglio 1988): 373–76. http://dx.doi.org/10.1152/jappl.1988.65.1.373.
Testo completoAbstract (sommario):
The rat hindlimb suspension model was used to ascertain the importance of ground reaction forces in maintaining bone and tendon homeostasis. Young female Sprague-Dawley rats were randomly assigned to either a suspended or a nonsuspended group. After 28 days, femur bones and patellar tendons were obtained for morphological and biochemical analyses. Prolonged suspension induced a significant change in the geometric configuration of the femur middiaphysis by increasing the minimum diameter (12%) without any significant alterations in cortical area, density, mineral, and collagen concentrations. Femur wet weight, length, DNA, and uronic acid concentrations of suspended animals were not significantly different from bones of nonsuspended rats. However, the collagen and proteoglycan concentrations in patellar tendons of suspended rats were 28% lower than the concentrations of matrix proteins in tissues obtained from nonsuspended animals. These data suggest that elimination of ground reaction forces induces alterations in tendon composition and femur diaphyseal shape by changing regional rates in bone remodeling and localized tendon strain. Therefore it appears that ground reaction forces are an important factor in the maintenance of cortical bone and patellar tendon homeostasis during weight-bearing conditions.
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Kerschan-Schindl, Katharina, Maria Papageorgiou, Ursula Föger-Samwald, Maria Butylina, Michael Weber e Peter Pietschmann. "Assessment of Bone Microstructure by Micro CT in C57BL/6J Mice for Sex-Specific Differentiation". International Journal of Molecular Sciences 23, n. 23 (23 novembre 2022): 14585. http://dx.doi.org/10.3390/ijms232314585.
Testo completoAbstract (sommario):
It remains uncertain which skeletal sites and parameters should be analyzed in rodent studies evaluating bone health and disease. In this cross-sectional mouse study using micro-computed tomography (µCT), we explored: (1) which microstructural parameters can be used to discriminate female from male bones and (2) whether it is meaningful to evaluate more than one bone site. Microstructural parameters of the trabecular and/or cortical compartments of the femur, tibia, thoracic and lumbar vertebral bodies, and skull were evaluated by µCT in 10 female and 10 male six-month-old C57BL/6J mice. The trabecular number (TbN) was significantly higher, while the trabecular separation (TbSp) was significantly lower in male compared to female mice at all skeletal sites assessed. Overall, bone volume/tissue volume (BV/TV) was also significantly higher in male vs. female mice (except for the thoracic spine, which did not differ by sex). Most parameters of the cortical bone microstructure did not differ between male and female mice. BV/TV, TbN, and TbSp at the femur, and TbN and TbSp at the tibia and lumbar spine could fully (100%) discriminate female from male bones. Cortical thickness (CtTh) at the femur was the best parameter to detect sex differences in the cortical compartment (AUC = 0.914). In 6-month-old C57BL/6J mice, BV/TV, TbN, and TbSp can be used to distinguish male from female bones. Whenever it is not possible to assess multiple bone sites, we propose to evaluate the bone microstructure of the femur for detecting potential sex differences.
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Lau, Beatrice Y., Val Andrew Fajardo, Lauren McMeekin, Sandra M. Sacco, Wendy E. Ward, Brian D. Roy, Sandra J. Peters e Paul J. LeBlanc. "Influence of high-fat diet from differential dietary sources on bone mineral density, bone strength, and bone fatty acid composition in rats". Applied Physiology, Nutrition, and Metabolism 35, n. 5 (ottobre 2010): 598–606. http://dx.doi.org/10.1139/h10-052.
Testo completoAbstract (sommario):
Previous studies have suggested that high-fat diets adversely affect bone development. However, these studies included other dietary manipulations, including low calcium, folic acid, and fibre, and (or) high sucrose or cholesterol, and did not directly compare several common sources of dietary fat. Thus, the overall objective of this study was to investigate the effect of high-fat diets that differ in fat quality, representing diets high in saturated fatty acids (SFA), n-3 polyunsaturated fatty acids (PUFA), or n-6 PUFA, on femur bone mineral density (BMD), strength, and fatty acid composition. Forty-day-old male Sprague–Dawley rats were maintained for 65 days on high-fat diets (20% by weight), containing coconut oil (SFA; n = 10), flaxseed oil (n-3 PUFA; n = 10), or safflower oil (n-6 PUFA; n = 11). Chow-fed rats (n = 10), at 105 days of age, were included to represent animals on a control diet. Rats fed high-fat diets had higher body weights than the chow-fed rats (p < 0.001). Among all high-fat groups, there were no differences in femur BMD (p > 0.05) or biomechanical strength properties (p > 0.05). Femurs of groups fed either the high n-3 or high n-6 PUFA diets were stronger (as measured by peak load) than those of the chow-fed group, after adjustment for significant differences in body weight (p = 0.001). As expected, the femur fatty acid profile reflected the fatty acid composition of the diet consumed. These results suggest that high-fat diets, containing high levels of PUFA in the form of flaxseed or safflower oil, have a positive effect on bone strength when fed to male rats 6 to 15 weeks of age.
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Wähnert, Dirk, Konrad L. Hoffmeier, Yves Stolarczyk, Rosemarie Fröber, Gunther O. Hofmann e Thomas Mückley. "Evaluation of a Customized Artificial Osteoporotic Bone Model of the Distal Femur". Journal of Biomaterials Applications 26, n. 4 (28 maggio 2010): 451–64. http://dx.doi.org/10.1177/0885328210367830.
Testo completoAbstract (sommario):
In the development of new implants biomechanical testing is essential. Since human bones vary markedly in density and geometry their suitability for biomechanical testing is limited. In contrast artificial bones are of great uniformity and therefore appropriate for biomechanical testing. However, the applied artificial bones have to be proved as comparable to human bone. An anatomical shaped artificial bone representing the distal human femur was created by foaming polyurethane. To get a bone model with properties of osteoporotic bone a foam density of 150 kg/m3 was used. The biomechanical properties of our artificial bones were evaluated against eight mildly osteoporotic fresh frozen human femora by mechanical testing. At the artificial bones all tested parameters showed a very small variation. In contrast significant correlation between bone mass density and tested parameters was found for the human bones. The artificial bones reached 39% of the compression strength and 41% of the screw pullout force of the human bone. In indentation testing the artificial bones reached 27% (cancellous) and 59% (cortical) respectively of the human bones strength. Regarding Shore hardness artificial bone and human bone showed comparable results for the cortical layer and at the cancellous layer the artificial bone reached 57% of human bones hardness. Our described method for customizing of artificial bones regarding their shape and bone stock quality provides suitable results. In relation to the as mildly osteoporotic classified human bones we assume that the biomechanical properties matching to serve osteoporotic bone.
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Nosho, Shuji, Ikue Tosa, Mitsuaki Ono, Emilio Satoshi Hara, Kei Ishibashi, Akihiro Mikai, Yukie Tanaka et al. "Distinct Osteogenic Potentials of BMP-2 and FGF-2 in Extramedullary and Medullary Microenvironments". International Journal of Molecular Sciences 21, n. 21 (27 ottobre 2020): 7967. http://dx.doi.org/10.3390/ijms21217967.
Testo completoAbstract (sommario):
Bone morphogenetic protein-2 (BMP-2) and fibroblast growth factor-2 (FGF-2) have been regarded as the major cytokines promoting bone formation, however, several studies have reported unexpected results with failure of bone formation or bone resorption of these growth factors. In this study, BMP-2 and FGF-2 adsorbed into atellocollagen sponges were transplanted into bone defects in the bone marrow-scarce calvaria (extramedullary environment) and bone marrow-abundant femur (medullary environment) for analysis of their in vivo effects not only on osteoblasts, osteoclasts but also on bone marrow cells. The results showed that BMP-2 induced high bone formation in the bone marrow-scarce calvaria, but induced bone resorption in the bone marrow-abundant femurs. On the other hand, FGF-2 showed opposite effects compared to those of BMP-2. Analysis of cellular dynamics revealed numerous osteoblasts and osteoclasts present in the newly-formed bone induced by BMP-2 in calvaria, but none were seen in either control or FGF-2-transplanted groups. On the other hand, in the femur, numerous osteoclasts were observed in the vicinity of the BMP-2 pellet, while a great number of osteoblasts were seen near the FGF-2 pellets or in the control group. Of note, FCM analysis showed that both BMP-2 and FGF-2 administrated in the femur did not significantly affect the hematopoietic cell population, indicating a relatively safe application of the two growth factors. Together, these results indicate that BMP-2 could be suitable for application in extramedullary bone regeneration, whereas FGF-2 could be suitable for application in medullary bone regeneration.
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Ward, Wendy E., Ana V. Piekarz e Debbie Fonseca. "Bone mass, bone strength, and their relationship in developing CD-1 mice". Canadian Journal of Physiology and Pharmacology 85, n. 2 (febbraio 2007): 274–79. http://dx.doi.org/10.1139/y07-020.
Testo completoAbstract (sommario):
Optimizing nutrition during development may provide effective prevention strategies to protect against osteoporosis during later life. Because the mouse model is commonly used to test nutritional interventions on bone health, the overall objective of this study was to determine how bone develops during the first 4 months of life by assessing bone mass (bone mineral content (BMC) and bone mineral density (BMD)) and biomechanical strength properties such as peak load in male and female CD-1 mice. Bone outcomes were assessed at 1 month intervals from 1 to 4 months of age. Femur and spine BMC and BMD at 3 months were similar to 4 months, indicating that the accumulation of bone mass occurs primarily during the first 3 months of life. In contrast, the timing of changes in peak load, a measure of bone strength, varied by skeletal site. Regression analyses demonstrated that femur BMC is a significant predictor of femur peak load at the femur midpoint and neck. The study findings suggest that nutritional interventions aimed at optimizing peak bone mass to prevent osteoporosis may be most effective during pubertal growth.
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Wei, Yi-Ping, Yu-Cheng Lai e Wei-Ning Chang. "Anatomic three-dimensional model-assisted surgical planning for treatment of pediatric hip dislocation due to osteomyelitis". Journal of International Medical Research 48, n. 2 (1 luglio 2019): 030006051985428. http://dx.doi.org/10.1177/0300060519854288.
Testo completoAbstract (sommario):
Management of pediatric septic coxarthritis and osteomyelitis of the femur is challenging, and the sequelae of multiplanar hip joint deformity with instability are difficult to reconstruct. The inadequacy of a suitable device for fixing small bones during pediatric osteotomy is a hindrance to the correction of subluxated hip joints and deformed femurs in children. Two-dimensional axial images and three-dimensional (3D) virtual models representing the patient’s individual anatomy are usually reserved for more complex cases of limb deformity. 3D printing technology can be used for preoperative planning of complex pediatric orthopedic surgery. However, there is a paucity of literature reports regarding the application of 3D-printed bone models for pediatric post-osteomyelitis deformity. We herein present a case of a 4-year-old boy who underwent treatment for post-osteomyelitis deformity. We performed corrective surgery with Pemberton osteotomy of the right hip, multilevel varus derotation osteotomy of the right femur, and immobilization with a hip spica cast. A 3D-printed bone model of this patient was used to simulate the surgery, determine the proper osteotomy sites, and choose the appropriate implant for the osteotomized bone. A satisfactory clinical outcome was achieved.
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Wu, Po-Kuei, Cheng-Wei Lee, Wei-Hsiang Sun e Chun-Li Lin. "Biomechanical Analysis and Design Method for Patient-Specific Reconstructive Implants for Large Bone Defects of the Distal Lateral Femur". Biosensors 12, n. 1 (22 dicembre 2021): 4. http://dx.doi.org/10.3390/bios12010004.
Testo completoAbstract (sommario):
This study aims to develop a generalizable method for designing a patient-specific reconstructive scaffold implant for a large distal lateral femur defect using finite element (FE) analysis and topology optimization. A 3D solid-core implant for the distal femur defect was designed to withhold the femur load. Data from FE analysis of the solid implant were use for topology optimization to obtain a ‘bone scaffold implant’ with light-weight internal cavity and surface lattice features to allow for filling with bone material. The bone scaffold implant weighed 69.6% less than the original solid-core implant. The results of FE simulation show that the bone repaired with the bone scaffold implant had lower total displacement (12%), bone plate von Mises stress (34%), bone maximum first principal stress (33%), and bone maximum first principal strain (32%) than did bone repaired with bone cement. The trend in experimental strain with increasing load on the composite femur was greater with bone cement than with the bone scaffold implant. This study presents a generalizable method for designing a patient-specific reconstructive scaffold implant for the distal lateral femur defect that has sufficient strength and space for filling with allograft bone.
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Mundane, Achal, Shraddha Awatade, Lina Bhoyar e Archana Mahakalkar. "Stature Estimation from Femur and Tibia Bone Using Regression Equation Method: A Pilot Study". UTTAR PRADESH JOURNAL OF ZOOLOGY 44, n. 19 (21 agosto 2023): 1–8. http://dx.doi.org/10.56557/upjoz/2023/v44i193610.
Testo completoAbstract (sommario):
Anthropometry plays a crucial role in the field of forensic anthropology, particularly in the identification of human remains. Among the various parameters used for personal identification, stature holds significant importance. It is a key factor in medico-legal investigations, especially when dealing with unknown fragmentary and mutilated remains. The objective of present pilot study was to develop a mathematical formula for estimating human stature based on the measurement of long bones, specifically the femur and tibia. A sample of 150 randomly selected girls, aged between 18 and 24 years, was chosen from Nagpur’s Institute of Forensic Science, Maharashtra. The length of the right tibia and femur bones was measured, calculated and regression formulae was derived to estimate stature for the female population of Maharashtra. To assess the relationship between bone length and stature, Pearson's correlation coefficient was employed and revealed regression coefficient (r) of 0.92 for the femur and 0.77 for the tibia, indicating a significant positive correlation between bone length and stature. Consequently, the findings of this study demonstrate that the length of the femur and tibia bones can serve as reliable predictors for estimating the stature of an individual. In conclusion, anthropometric measurements, particularly those involving long bones such as the femur and tibia, hold immense value in the identification of human remains in the field of forensic anthropology.
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Vitkovic, Nikola, Jelena Milovanovic, Nikola Korunovic, Miroslav Trajanovic, Milos Stojkovic, Dragan Misic e Stojanka Arsic. "Software system for creation of human femur customized polygonal models". Computer Science and Information Systems 10, n. 3 (2013): 1473–97. http://dx.doi.org/10.2298/csis121004058v.
Testo completoAbstract (sommario):
Geometrically accurate and anatomically correct threedimensional geometric models of human bones or bone sections are essential for successful pre-operative planning in orthopedic surgery. For such purposes, 3D polygonal models of bones are usually created based on Computer Tomography (CT) or Magnetic Resonance Imaging (MRI) data. In cases where there is no CT or MRI scan, or part of bone is missing, such three-dimensional polygonal models are difficult to create. In these situations predictive bone models are commonly used. In this paper, the authors describe the developed a software system for creation of Human Bones Customized Polygonal models (HBCP) which is based on the use of the predictive parametric bone model. The software system enables creation of patient-specific polygonal models of bones, by using only a limited number of parameter values. Parameter values can be acquired from volumetric medical imaging methods (CT, MRI), or from two-dimensional imaging methods (i.e. Xray). This paper introduces the new approach to the process of creation of human bones geometrical models which are based on the anatomical landmark points. Testing of the HBCP for the cases of femur bone samples has shown that created bone and bone region models are characterized by a good level of anatomical and morphometric accuracy compared to the results presented in similar researches.
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Shi, Huijuan, Li Ding, Yanfang Jiang, Haocheng Zhang, Shuang Ren, Xiaoqing Hu, Zhenlong Liu, Hongshi Huang e Yingfang Ao. "Bone Bruise Distribution Patterns After Acute Anterior Cruciate Ligament Ruptures: Implications for the Injury Mechanism". Orthopaedic Journal of Sports Medicine 8, n. 4 (1 aprile 2020): 232596712091116. http://dx.doi.org/10.1177/2325967120911162.
Testo completoAbstract (sommario):
Background: Bone bruises observed on magnetic resonance imaging (MRI) after an anterior cruciate ligament (ACL) injury could provide significant information about ACL injury mechanisms. Purpose/Hypothesis: The purpose of this study was to investigate common bone bruise patterns after an ACL injury. It was hypothesized that the most common bone bruise distribution pattern would be only the lateral side of both the femur and tibia. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Knee MRI scans of patients who underwent acute ACL reconstruction from August 2016 to August 2018 at our institution were selected. Imaging sequences in the sagittal and coronal planes were used for determining the bone bruise location in the lateral-medial and anterior-posterior directions, respectively. The presence, location, and intensity of bone bruises within specific compartments of the tibia and femur were documented. The relative bone bruise patterns of the tibia and femur were classified and analyzed. Results: A total of 207 patients (165 men, 42 women) met the inclusion criteria from a total of 4209 ACL reconstruction cases. The most common relative bone bruise pattern was located on only the lateral side of both the femur and the tibia (44.4%), followed by the lateral and medial sides of both the femur and tibia (29.0%). For the pattern found on the lateral and medial sides of both the femur and tibia, the bone bruises on only the lateral side of both the tibia and femur were more severe ( P < .001 and P < .001, respectively) and more anterior ( P < .001 and P < .001, respectively) than those on only the medial side. Conclusion: The most common relative bone bruise pattern observed was on only the lateral side of both the tibia and femur. Bone bruises on the lateral side were more severe than those on the medial side in patients with bone bruises on the lateral and medial sides of both the femur and tibia. Anterior translation of the tibia relative to the femur occurred during an ACL injury based on the location of bone bruises in the anterior-posterior direction.