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1

Wielka moc w małej cząsteczce : właściwości i zastosowania bisfosfonianów

Kozicka Dominika, Socha Karolina, Szarek Jarosław, Kuźnik Anna

Wiadomości Chemiczne

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2023

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[Z] 77, 1-2

55--73

EN

Bisphosphonates (BPs) are a group of compounds that are extensively studied around the world. Bisphosphonates are organophosphorus compounds characterized by the presence of the P-C-P skeleton. They are synthetic, thermally stable, and hydrolysis-resistant pyrophosphate analogs that occur naturally in living organisms. BPs have the ability to chelate metals such as magnesium and calcium which results in their high affinity to bone tissue. [1] The above factors determine their biological properties and the wide range of related applications. Bisphosphonates have an established position on the pharmaceutical market and have been used in medicine for many years, mainly as anti-resorptive drugs. They are considered the gold standard in the prevention and treatment of many different bone diseases, such as osteoporosis or Paget disease. [1] The therapeutic potential of bisphosphonates, however, is not limited to the treatment of bone diseases, as more and more reports about their other useful biological properties appear in the literature. [2] The usefulness of bisphosphonates in imaging diagnostics and drug delivery systems is also being explored. [3-5] The following article provides a short literature review on BPs, mainly their structure, properties, and mechanism of action, as well as their current and potential applications.

2

Using X-ray diffraction in characterization of bone remodeling and nanocomposites in ovariectomized rats osteopenia model

Kostyshyn Nazar, Gzhegotskyi Mechyslav, Kostyshyn Liubov, Yarova Oksana, Kulyk Yuriy, Mudry Stepan

Polish Journal of Medical Physics and Engineering

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2021

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Vol. 27, Iss. 2

157--163

EN

Sedentary lifestyle and physiological menopause are among the risk factors of osteopenia, especially in elderly people. However, bone mineral density decrease can also be observed in young individuals, for instance, due to deficiency of female sex hormones after surgical interventions, particularly ovariectomy. Our research enabled us to assess the efficacy of whole-body vibration in preventing the loss of bone mineral density in the ovariectomy rat osteopenia model. Thus, whole-body vibration with acceleration level 0.3 g and frequency 50 Hz was used on young female rats, which had been subjected to ovariectomy (n = 18). It had been conducted for 24 weeks, exposure time – 30 minutes per day, 5 times a week. Assessment of mineral component loss of the tibia was performed by means of X-ray diffraction. Bone remodeling was assessed by determining hormones: parathyroid hormone and calcitonin, Ca and P in the blood. X-ray diffraction is an effective method, which enables the evaluation a nanocomposites structure of the bone tissue in the experiment. In the article, we applied this method to determine the loss of bone mineral mass after ovariectomy and the impact of wholebody vibration under such conditions. In the ovariectomy group, the volume of a mineral component significantly decreased starting already from the 16th week (р<0.05) versus control. However, in the group with ovariectomy + wholebody vibration, the loss of a mineral component was insignificant during 8-16 weeks of the investigation, compared with the control group. On the 24th day, the spectrums almost did not differ from ovariectomized rats group. Meanwhile, hormone levels changed in ovariectomized rats group. It should be emphasized that the aforementioned whole-body vibration parameters do not cause severe bone damage or further negative consequences.

3

Phytoestrogens from legume seeds and their role in the prevention of osteoporosis in postmenopausal women®

Stachoń Aleksandra, Lachowicz Katarzyna, Skolmowska Dominika, Kołota Aleksandra

Postępy Techniki Przetwórstwa Spożywczego

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2020

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nr 2

185--194

EN

Menopause is associated with numerous changes and disturbances in a woman’s body that reduce her quality of life. They include, among others, disturbances in bone metabolism and with the consequence developing osteopenia and osteoporosis as a result of estrogen deficiency in the body. Legume seeds and their products are a rich source of phytochemicals which, due to their chemical structure similar to estrogens, are estrogenic indicators. The article presents the current state of knowledge on their impact on bone metabolism. Its knowledge is important in planning the nutrition of perimenopausal women due to the knowledge of the risk of developing osteoporosis in this population group.

PL

Menopauza wiąże się z licznymi zmianami i zaburzeniami w organizmie kobiety, które obniżają jakość jej życia. Należą do nich m.in. zaburzenia metabolizmu kostnego i w konsekwencji rozwijająca się osteopenia i osteoporoza będące skutkiem niedoboru estrogenów w organizmie. Nasiona roślin strączkowych i produkty z nich otrzymywane są bogatym źródłem fitozwiązków, w tym o budowie chemicznej podobnej do estrogenów, wykazujących właściwości estrogenne. W artykule przedstawiono aktualny stan wiedzy na temat ich wpływu na metabolizm kostny. Jego znajomość jest istotna w planowaniu żywienia kobiet w wieku okołomenopauzalnym ze względu na możliwość zmniejszenia ryzyka rozwoju osteoporozy w tej grupie populacyjnej.

4

Zastosowanie densytometru DXA w diagnostyce osteoporozy

Błaszczyk Bartłomiej, Błaszczyk Tomasz

Inżynier i Fizyk Medyczny

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2020

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Vol. 9, nr 3

212--215

PL

Osteoporoza jest układową chorobą kości charakteryzującą się niską masą kostną i zaburzeniami struktury tkanki kostnej, a w konsekwencji zwiększoną podatnością na złamania. Złamania trzonów kręgów są jednymi z najczęstszych złamań osteoporotycznych, często pozostają nieme klinicznie, a ich obecność wiąże się ze zwiększoną śmiertelnością. Wczesne wykrycie osteoporozy i identyfikacja złamań trzonów kręgów pozostają głównymi celami diagnostyki. Densytometria (dual-energy X-ray absorptiometry – DXA) jest jedyną metodą pomiaru gęstości mineralnej kości (bone mineral density – BMD) mającą zastosowanie w praktyce klinicznej. Badanie densytometryczne można przeprowadzić w obrębie kości udowej, kręgosłupa odcinka lędźwiowego – metoda centralna DXA. Badanie centralne DXA, wykorzystujące odpowiedni rodzaj densytometru, jest uzupełniającą metodą w diagnostyce osteoporozy, monitorowaniu skuteczności leczenia oraz we wczesnej diagnostyce złamań trzonów kręgów.

EN

Osteoporosis is a systemic bone disease characterized by low bone mass and bone structure disorders, and consequently, by increased susceptibility to fractures. Vertebral fracture is one of the most common osteoporotic fractures. Vertebral fractures often remain clinically silent, and their presence is associated with increased mortality. Early detection of osteoporosis and identification of vertebral fractures remain the main aims of diagnosis. Densitometry (dual-energy X-ray absorptiometry, DXA) is the only method of measuring bone mineral density (BMD) applicable in clinical practice. Densitometry can be performed on the femur, or lumbar spine – central DXA method. The central DXA examination, using the appropriate type of densitometer, is a complementary method in the diagnosis of osteoporosis, monitoring the effectiveness of treatment and in the early diagnosis of vertebral fracture.

5

Comparison of Machine Learning Models to Predict Risk

Cuaya-Simbro German, Perez-Sanpablo Alberto-Isaac, Muñoz-Meléndez Angélica, Quiñones Ivett, Morales-Manzanares Eduardo-F., Nuñez-Carrera Lidia

Foundations of Computing and Decision Sciences

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2020

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Vol. 45, No. 2

65--77

EN

Falls are a multifactorial cause of injuries for older people. Subjects with osteoporosis are more vulnerable to falls. The focus of this study is to investigate the performance of the different machine learning models built on spatiotemporal gait parameters to predict falls particularly in subjects with osteoporosis. Spatiotemporal gait parameters and prospective registration of falls were obtained from a sample of 110 community dwelling older women with osteoporosis (age 74.3 ± 6.3) and 143 without osteoporosis (age 68.7 ± 6.8). We built four different models, Support Vector Machines, Neuronal Networks, Decision Trees, and Dynamic Bayesian Networks (DBN), for each specific set of parameters used, and compared them considering their accuracy, precision, recall and F-score to predict fall risk. The F-score value shows that DBN based models are more efficient to predict fall risk, and the best result obtained is when we use a DBN model using the experts’ variables with FSMC’s variables, mixed variables set, obtaining an accuracy of 80%, and recall of 73%. The results confirm the feasibility of computational methods to complement experts’ knowledge to predict risk of falling within a period of time as high as 12 months.

6

Skład chemiczny i aktywność biologiczna gruszyczki Pyrola calliantha H. Andr.

Guo Jinying, Ma Liang, Lu Hong, Miao Zefeng, Guo Xuxia

Przemysł Chemiczny

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2019

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T. 98, nr 5

715--718

PL

Gruszyczka z gatunku Pyrola calliantha H. Andr. jest jednym z najważniejszych tradycyjnych chińskich ziół leczniczych. Jest bogata w substancje bioaktywne o właściwościach farmakologicznych i powszechnie stosowana jako środek zapobiegający starzeniu, regulator ciśnienia krwi i wzmacniacz odporności. Związki chemiczne, które wyizolowano z rośliny poprzez destylację z parą wodną zidentyfikowano metodą chromatografii gazowej i spektrometrii mas (GS-MS) oraz zbadano ich wpływ na proliferację osteoblastów in vitro. Główne związki fitochemiczne zawarte w ekstrakcie to kwas 4-heksylo-2,5-dihydro-2,5-diokso-3-pirośluzowy i ftalan diizobutylu. Ekstrakt zwiększał proliferację osteoblastów in vitro oraz w znacznym stopniu zwiększał udział osteoblastów w cyklicznym procesie proliferacji.

EN

Volatile org. compds. were sepd. from Pyrola calliantha H. Andr. herbs by steam distn. and analyzed by gas chromatog. with mass spectrometry. The distillate contained palmitic acid (26.6%), cedrol (15.25%), 6,10,14-trimethyl- 2-pentadecanone (8.57%), oleic acid (7.35%), phytol (4.22%) and 1-tridecanecarboxylic acid (2.10%). The essence enhanced the proliferation of osteoblasts.

7

Quantitative and qualitative assessment of the impact of osteoporosis on endplate layers

Wojtkow Magdalena, Kielbowicz Zdzislaw, Biezynski Janusz, Pezowicz Celina

Biocybernetics and Biomedical Engineering

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2019

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Vol. 39, no. 3

797--805

EN

The endplate (EP) is a composite structure made of osseous and cartilage components that separates the intervertebral disc from the vertebral body. As an intermediary link between rigid bone tissue and the flexible intervertebral disc, EP is affected by structural changes as well as changes in biomechanical properties of both these elements caused by pathological changes in the spine. One of the modern civilization hazards related to the skeletal system are osteoporotic changes. Although the influence of osteoporosis on vertebral bodies has been extensively researched, there is still a lack of information about its impact on the structure of the endplate itself. The aim of this study was to carry out a quantitative and qualitative assessment of the impact of osteoporosis on individual layers of EP. An animal model of the cervical and thoracic vertebrae was used. The analyses were conducted on two study groups: control (healthy sheep) and osteoporotic (with induced osteoporosis). Microstructural changes were analyzed using a micro-CT scanner, while mechanical parameters were analyzed using the microindentation test. There were no statistically significant differences in the analyzed parameters between cranial and caudal endplates. The performed tests showed significant changes in the trabecular microarchitecture of the endplate layer caused by osteoporosis. Despite the presence of morphometric changes in the osteoporotic group, no significant changes were observed in the mechanical properties of analyzed structures. A comparison of the mechanical parameters obtained for healthy endplates of the sheep model showed a high correlation with literature data for the human model.

8

Investigation of pullout strength in different designs of pedicle screws for osteoporotic bone quality using finite element analysis

Yang Shih-Chieh, Liu Pao-Hsin, Tu Yuan-Kun

Acta of Bioengineering and Biomechanics

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2019

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Vol. 21, no. 3

57--66

EN

The purpose of this study was to investigate pullout strength of three types of pedicle screws with and without cement augmentation in osteoporotic bone using finite element analysis. Methods: Twelve 3D finite element models were created to investigate the effect of pullout strength when comparing between pedicle screw types and bone cement clouds. The bottom side of bone block model was constrained and U-shape head was applied 1 mm in direction of longitudinal axis of pedicle screw to perform pullout resistance. The material properties of the FEA was set as linear elastic, homogenous, isotropic condition. The element sensitivity of convergence testing has been performed and variation of the sequential analytical results was less than 3%. Results: The results showed that the maximum total reaction force (133.8 N) was detected in the model of cannulated pedicle screw combined with a central pin with 4 ml cement augmentation, but, in contrast, the minimum total reaction force (106.8 N) was discovered in the model of cannulated pedicle screw without cement. A strong relationship (r = 0.9626) is found in comparison with the biomechanical results between pullout strength of sawbone testing and reaction forces of the FEA. Conclusions: The study concludes that the cannulated pedicle screw can not only provide an inner guider for cement flow and increase bending resistance (deflection effect) when a central pin is selected, but also can improve the pullout strength in the osteoporotic bone to add cement augmentation. The design of the cannulated pedicle screw is suggested for poor bone quality to change pullout failure.

9

Stimulation of osteogenezis to fight with osteoporozis

Pawlikowski M.

Auxiliary Sciences in Archaeology, Preservation of Relics and Environmental Engineering

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2018

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nr 24

1--5

EN

Osteoporosis is not only process of destruction of bones. Elements removed from bones may migrate to soft tissue and crystalize there leading to many health troubles and often to death. Phenomenon of osteogenesis were described as biological- mineralogical reactions. Discussion concerning osteogenesis is presented in frames of bone creation and destruction. One can conclude the natural processes of none formation is possible use to fight with osteoporosis.

PL

Osteoporoza nie jest wyłącznie procesem niszczenia kości. Pierwiastki wyprowadzane z kości mogą migrować do tkanek miękkich i tu krystalizować powodując wiele problemów zdrowotnych a nawet śmierć. Przedstawiono proces osteogenezy(kościotworzenia) jako zjawisko biologiczno-mineralogiczne. Dyskusje dotyczącą osteogenezy przedstawiono jako tworzenie i niszczenie kości. Stwierdzono, że naturalne procesy formowania kości można wykorzystać do walki z osteoporozą.

10

The influence of osteoporotic bone structures of the pelvic-hip complex on stress distribution under impact load

Arkusz K., Klekiel T., Niezgoda T. M., Będziński R.

Acta of Bioengineering and Biomechanics

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2018

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Vol. 20, no. 1

29--38

EN

Purpose: The aim of this study was to determine the effect of bone mineral density (BMD) on the stress distribution in pelvic-hip complex (PHC) model which included bone structures and soft tissues. Bone mass changes in osteoporosis and osteopenia were considered in this analysis. In addition, the relations between force direction and stress distribution causing PHC fractures were determined. Methods: This paper presents the development and validation of a detailed 3D finite element model with high anatomical fidelity of the PHC and BMD changes in trabecular and cortical bones, modelled based on CT scans. 10 kN loading was induced on a model consisting of 8 ligaments, the pelvis, sacrum, femur in front and side directions. Results: For validation, the results of this model were compared to physiological stress in standing position and previous results with high-energy crashes under side impact load. Analysis of side-impact indicated the influence of BMD on femoral neck fractures, acetabular cartilage and sacroiliac joint delaminations. Front-impact analysis revealed the inferior pubic ramus, femoral neck fractures and soft tissue injuries, i.e., acetabular cartilage and symphysis pubis in osteoporosis and osteopenia. Conclusions: The elaborated PHC model enables effective prediction of pelvis injuries in high-energy trauma, according to Young-Burgess classification, and the determination of the influence of BMD reduction on pelvis trauma depending on force direction. The correlation between BMD and stress distribution causing varying injuries was determined.

11

Pullout evaluation of sawbone experiment in different types of pedicle screws combined with bone cement augmentation for severe osteoporotic spine

Yang S.-C., Liu P.-H., Tu Y.-K.

Acta of Bioengineering and Biomechanics

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2018

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Vol. 20, no. 2

55--64

EN

Purpose: The conventional screw is unable to provide enough screw-bone interface strength for osteoporotic cencellous bone, and complications resulting from loosening or failure of the implants remain a significant clinical problem. Hence, the purpose of this study is to investigate pullout strength and energy in three types of the pedicle screws, including conventional solid pedicle screw, cannulated pedicle screw, and cannulated pedicle screw with a central pin, using osteoporotic sawbone test block with different bone cement volumes through pullout force testing. Methods: The control group (n = 15) of the osteoporotic sawbone test block includes groups A, B, and C to reflect three types of the pedicle screws without bone cement augmentation. The cemented group (n = 45) of the osteoporotic sawbone test block includes groups D1, D2, D3, E1, E2, E3, F1, F2, and F3 to reflect three types of the pedicle screws with PMMA bone cement of 2, 3, and 4 mL augmentation. Results: The results showed that the pullout strength and energy in the cemented group were significantly larger than that in the control group. Moreover, the best performances of the pullout strength and energy in the cemented group were evidenced obviously in the case of cannulated pedicle screw with a central pin with 4 mL bone cement augmentation. Conclusions: This study concludes that cement argumentation in the cannulated pedicle screw with a central pin can increase a pullout strength of pedicle screw for severe osteoporotic patients while bone cement of injective volume is limited.

12

Leczenie złamań szyjki kości udowej

Cwanek J., Trybuchowicz A., Ciećkiewicz A., Bać D.

Problemy Nauk Stosowanych

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2017

|

T. 6

119--126

PL

Wstęp i cele: Starość jest naturalnym procesem fizjologicznym. W wieku geriatrycznym stwierdza się (między innymi): zmniejszoną wydolność fizyczną, osteoporozę, spowolnienie psychoruchowe, występowanie upadków z „własnej wysokości”. Konsekwencją upadków może być przerwanie ciągłości kości. Do najtrudniejszych w leczeniu należą złamania szyjki kości udowej, występujące najczęściej między 7-9 dekadą życia. Celem pracy jest podanie metod leczenia złamań szyjki kości udowej w grupie pacjentów pomiędzy 51-100 rokiem życia. Materiał i metody: Materiał badań stanowiło 345 pacjentów leczonych z powodu złamań szyjki kości udowej w latach 2013-2015 (252 kobiet i 93 mężczyzn). Analizowano średni wiek mężczyzn i kobiet, ilość złamań występujących w poszczególnych miesiącach, stronę złamania, okres hospitalizacji w zależności od stosowanego leczenia. Wyniki: Średni wiek kobiet wynosił 80,3 (s=10,8), mężczyzn 75,5 lat życia (s=8,6). Złamania częściej rozpoznano po stronie lewej (u 208 leczonych) i w miesiącach: styczniu oraz lutym (w sumie u 96 poszkodowanych), następnie w listopadzie i w grudniu (u 80 pacjentów), znacznie rzadziej od maja do października (po kilkanaście złamań w każdym miesiącu). Leczeniu operacyjnemu poddano 332 pacjentów (96,2% ogółu chorych). Metodami nieoperacyjnymi leczono 13 chorych. Sztuczne stawy biodrowe wszczepiono 319 pacjentom (połowicze 191, całkowite 128 chorym). U pozostałych 13 pacjentom złamane zespolono metalem (6 chorym płytą DHS, 4 śrubami gąbczastymi, 3 prętami Endera). Najstarszą grupę pacjentów stanowili chorzy leczeni metodami nieoperacyjnymi (x=87,5 lat życia; s=7,1), następnie pacjenci którym implantowano połowicze sztuczne stawy biodrowe (x=80,7 lat; s=5,1). Średni wiek chorych, którym wszczepiono całkowite endoprotezy biodra wynosił 77,0 lat życia (s=6,3). Najmłodszą grupę stanowili pacjenci, którym złamaną szyjkę kości udowej zespolono metalem (x=60,0 lat; s=5,2). Prawie 13 dni hospitalizowani byli w szpitalu chorzy którym wszczepiono całkowite sztuczne stawy biodrowe (x=12,9 dni; s=5,1). O półtora dnia krócej przebywali w szpitalu pacjenci którym implantowano połowicze sztuczne stawy biodrowe (x=11,3 dni; s=5,2). Wszyscy chorzy, którym wszczepiono całkowite i połowicze sztuczne stawy biodrowe, w dniu wypisu ze szpitala, poruszali się samodzielnie z pomocą dwóch lasek łokciowych lub balkonika. Najkrócej hospitalizowani byli pacjenci którym złamanie zespolono metalem (x=8,7 dni; s=4,8), o jeden dzień dłużej chorzy leczeni metodami nieoperacyjnymi (x=9,5 dni; s=5,1). Wnioski: Złamania szyjki kości udowej znacznie częściej występowały w grupie kobiet oraz w miesiącach „zimowych”. Najczęściej stosowaną metodą leczenia było wszczepienie endoprotezy biodra, w miejsce złamanej szyjki i usuniętej głowy kości udowej. Po implantacji sztucznego stawu można rozpocząć wczesną rehabilitację, która przywraca możliwość poruszania się w ciągu kilku dni po przebytym zabiegu. Leczenie metodami nieoperacyjnymi powinno być stosowane jedynie u pacjentów, którzy z powodu złego stanu zdrowia nie mogą być poddani zabiegowi operacyjnemu.

EN

Introduction and aims: Old age is a natural physiological process. Older people very often experience the following: psychomotor retardation, difficulties in walking, falling for no obvious reason, decreased physical fitness and osteoporosis. Frequent falling may cause breaking of the continuity of the bone. Proximal femur fractures occurring between the ages of 70-90 are the most difficult to treat. The objective of this paper is specifying treatment methods for femoral neck fractures in a group of patients between the ages of 51-100 (x=79,0; s=10,1). Material and methods: Research was performed on 345 patients treated in the years 2013-2015 due to femoral neck fractures (252 women and 93 men). Patients’ age, place of residence (city, countryside), number of fractures in particular months of the year, side of fracture and period of hospitalization depending on the applied treatment methods were all analysed. Results: The average age for women was 80,3 years (s=10,8), while the average age for men was 75,5 years (s=8,6). Fractures were more frequent on the left side (in 208 of patients). Fractures were more frequent in the following months: January and February (96 fractures in total), then in November and December (80 patients), and rarely in the period from May to October (several femoral neck fractures in each month). 332 patients underwent surgical treatment (96,2% of patients in total). Only 13 patients were treated using nonsurgical methods. Artificial hip joints were implanted to 319 patients (partial in 191 patients, complete in 128 patients). In the remaining 13 patients femoral neck fractures were fixed with metal (4 patients with spongy screws, 6 with DHS system and 3 with Ender nails). The oldest group of patients included patients treated using nonsurgical methods (x=87,5 years; s=7,1), then there were patients with partial artificial hip joints (x=80,7 years; s=5,1). The average age of patients, who had complete hip endoprosthesis implanted was 77,0 years (s=6,3). The youngest group were patients, who had their fractured femoral neck fixed with metal (x=60,0 years; s=5,2). Patients with complete hip endoprosthesis were hospitalized almost 13 days (x=12,9 days; s=5,1). Patients with partial artificial hip joints implanted stayed at the Orthopaedics Department over a day shorter (x=11,3 days; s=5,2). On the day of discharge all patients with artificial hip joints were moving on their own with the help of two crutches of a walker. Patients, who had their fractured femoral neck fixed with metal stayed at the hospital for the shortest period (x=8,7 days; s=4,8), i.e. a day longer than patients treated with nonsurgical methods (x=9,5 days; s=5,1). Conclusions: Femoral neck fractures are significantly more frequent in a group of women, patients living in the countryside and during winter months. The most commonly used method was implanting hip endoprosthesis in the place of a fractured neck and removal of the head. After implanting the artificial joint patients may start rehabilitation, which allows them to move on their own in just a few days after the surgery. Treatment with nonsurgical methods should be used in patients, who cannot undergo surgery due to bad condition of health.

13

The finite element analysis of osteoporotic lumbar vertebral body by influence of trabecular bone apparent density and thickness of cortical shell

Ardatov O., Maknickas A., Kačianauskas R., Alekna V., Tamulaitienė M.

Acta Mechanica et Automatica

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2017

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Vol. 11, no. 4

185--292

EN

Osteoporosis causes the bone mass loss and increased fracture risk. This paper presents the modelling of osteoporotic human lumbar vertebrae L1 by employing finite elements method (FEM). The isolated inhomogeneous vertebral body is composed by cortical outer shell and cancellous bone. The level of osteoporotic contribution is characterised by reducing the thickness of cortical shell and elasticity modulus of cancellous bone using power-law dependence with apparent density. The strength parameters are evaluated on the basis of von Mises-Hencky yield criterion. Parametric study of osteoporotic degradation contains the static and nonlinear dynamic analysis of stresses that occur due to physiological load. Results of our investigation are presented in terms of nonlinear interdependence between stress and external load.

14

Badania porowatości głowy kości udowej człowieka jako wskaźnik osteoporozy

Pawlikowski M., Bieniek A., Motyka J., Juśko K., Niedźwiedzki T.

Auxiliary Sciences in Archaeology, Preservation of Relics and Environmental Engineering

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2015

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nr 19

1--32

PL

Badaniom poddano głowy kości udowej usunięte podczas totalnej alloplastyki stawu biodrowego. Badania porowatości tych samych próbek kości wykonano trzema metodami: metodą densymetryczną, pomiarów mikroskopowych oraz metodą wykorzystywaną w określaniu porowatości skał. Każda z wykorzystanych metod dała inne wyniki. Wyniki badań podsumowano i przedyskutowano.

EN

The porosity of heads of femur removed during general alloplastic surgery of iliac joint were examined using three various methods i.e.: densitometry, microscopic measurement and using classic method preferred for determination of porosity of rocks. Results of these examination were compared and show various value of porosity of the same samples.

15

Wstępna ocena właściwości strukturalno-elektrycznych w zakresie niskich częstotliwości biomateriałowego modelu doświadczalnego kości długich w stanie patologicznym

Uklejewski R., Czapski T., Winiecki M.

Engineering of Biomaterials

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2014

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Vol. 17, no. 126

12--22

PL

Przedstawiono wyniki doświadczalnych badań porównawczych dotyczących metod wytworzenia biomateriałowego modelu kości długich w stanie patologicznym, tj. nie w pełni zmineralizowanych (stan osteomalacji) oraz o obniżonym kościotworzeniu (stan osteoporotyczny), otrzymanego na bazie wołowych kości udowych, z wykorzystaniem stosowanych w inżynierii biomateriałów metod częściowego odbiałczania i częściowego odwapniania. Ten biomateriałowi model kości długich jest niezbędny do prowadzenia doświadczalnych badań właściwości strukturalno--elektrycznych kości długich w celu zbudowania prototypowego systemu pomiarowo-obliczeniowego do wyznaczania gęstości i parametrów porosprężystych kości długich prawidłowych i osteoporotycznych oryginalną nieinwazyjną metodą elektroosteodensytometrii (zgłoszenie patentowe krajowe i międzynarodowe). Proces odbiałczania prowadzono porównawczo z użyciem roztworów NaOCl, H2O2, KOH i NaOH, natomiast proces odwapniania próbek kości wołowych prowadzono porównawczo z użyciem roztworów HNO3, HCl i EDTA oraz w mieszaninie roztworów HNO3 i HCHO. Zbadano kinetykę przeprowadzonych procesów, monitorując stężenia białka oraz wapnia w zastosowanych roztworach w funkcji czasu. Na podstawie zbadanych przebiegów procesów możemy obecnie zarekomendować do wytworzenia biomateriałowych modeli doświadczalnych kości długich w stanie patologicznym: o obniżonym kościotworzeniu – odbiałczanie z użyciem 7% roztworu nadtlenku wodoru (H2O2), a dla nie w pełni zmineralizowanych – odwapnianie z użyciem 0,5 M roztworu kwasu solnego (HCl). Przedstawiono pilotażowe wyniki doświadczalnej analizy właściwości strukturalno-elektrycznych biomateriałowego modelu kości długiej w stanie obniżonego kościotworzenia (badano trzy częściowo odbiałczone kości udowe wołowe) z wypełnieniem porów modelu wieloelektrolitowym płynem fizjologicznym Ringera, w zakresie niskich częstotliwości (od 20 Hz do 10 kHz) i w zależności od lokalizacji badanej próbki wzdłuż trzonu kości długiej. Stwierdzono, że: 1) wartości modułu impedancji elektrycznej jednostkowej |Z1| [Ω/cm] trzonu modelowej kości długiej osteoporotycznej maleją bardzo wyraźnie w funkcji częstotliwości w zakresie od 20 Hz do 500 Hz; od częstotliwości 500 Hz do 2 kHz zmiany wartości |Z1| są niewielkie, a powyżej częstotliwości 2 kHz wartość modułu impedancji jednostkowej |Z1| praktycznie nie zależy od zmian częstotliwości; 2) średnia wartość modułu impedancji elektrycznej jednostkowej |Z1| trzonu modelowej kości długiej osteoporotycznej okazała się względnie stała wzdłuż długości trzonu kości i wynosiła ok. 670 Ω/cm dla częstotliwości 100 Hz oraz ok. 630 Ω/cm dla częstotliwości 10 kHz. Otrzymane pilotażowe wyniki pomiarów parametrów elektrycznych określających właściwości strukturalno-elektryczne kości długich osteoporotycznych wymagają potwierdzenia na większej liczbie próbek trzonowo-kostnych częściowo odbiałczanych; planujemy też poszerzenie analizy doświadczalnej właściwości strukturalno--elektrycznych kości długich o obniżonej mineralizacji (częściowo odwapnionych).

EN

We present the results of a comparative experimental study on methods considered for the manufacture of a biomaterial model of long bones in a pathological state, i.e. insufficiently mineralized bone (osteomalacia) and reduced osteogenesis (osteoporosis), obtained from bovine femoral bone, using methods applied in the engineering of biomaterials such as partial deproteinization and partial demineralization. The biomaterial model is required for experimental research into the structural-electrical properties of long bones, which will be carried out to build a prototype for a measurement system for the evaluation of bone densitometry and poroelastic properties with the use of an original and non-invasive method of electroosseodensitometry (Polish and international patent applications). The kinetics of chemical bone deproteinization processes in NaOCl, H2O2, KOH and NaOH solutions and chemical bone demineralization processes in HNO3, HCl, EDTA solutions and in a mixture of HNO3 and HCHO were comparatively studied and the protein and calcium contents were monitored as a function of time. On the basis of the functional graphs obtained from the observed processes, we can currently recommend the following conditions for manufacturing a biomaterial model of long bones in a pathological state: deproteinization using a 7% solution of hydrogen peroxide (H2O2) to produce a model of bone in a state of reduced osteogenesis and decalcification with 0.5 M hydrochloric acid (HCl) to produce a model of insufficiently mineralized bone. The results of a pilot experimental analysis of the structural-electrical properties of the biomaterial model of long bones are presented for a state of reduced bone formation (osteoporotic; three partially deproteinized bovine femurs were examined). The bone pores of the model were filled with physiological multielectrolyte Ringer’s saline and assessed in a low frequency range (20 Hz to 10 kHz) as a function of the location of bone shaft samples along the diaphysis. It was found that: 1) values of the modulus of the unit electrical impedance |Z1| [Ω/cm] of the bone shaft of the model osteoporotic long bone decreased very clearly as a function of frequency in the range from 20 Hz to ca. 500 kHz; from a frequency of 500 Hz to 2 kHz, the changes in the |Z1| value were small, and above 2 kHz, the |Z1| value practically did not depend on frequency changes. 2) The mean value of the modulus of the unit electrical impedance |Z1| of the bone shaft of the model osteoporotic long bone was found to be relatively constant along the length of the bone shaft and was about 670 Ω/cm for a frequency of 100 Hz and about 630 Ω/cm for a frequency of 10 kHz. The results of the preliminary study on the structural-electrical properties of long bone shafts in a pathological (osteoporotic) state require confirmation in a full experimental study on a larger number of model osteoporotic long bones; we are also planning to extend the experimental analysis to the structural-electrical properties of long bones with impaired mineralization (partially decalcified).

16

Preparation and characterization of drug delivery carriers for local administration of sodium alendronate

Posadowska U., Moreira A., Martins R., Pamuła E.

Engineering of Biomaterials

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2013

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Vol. 16, no. 119

8--12

EN

Osteoporosis is often treated with the use of sodium alendronate - a drug that inhibits osteoclast-mediated bone resorption and regulates rate of bone turnover. However the disadvantage of oral administration of sodium alendronate is poor drug absorption from the gastrointestinal track and severe adverse effects. Therefore we propose local sustained drug delivery systems based on poly(lactide-co-glycolide) (PLGA) micro- and nanocarriers, which can be administered directly by simple injections to the required place in the body. In this study we encapsulated sodium alendronate into PLGA micro- and nanospheres via a double-emulsification technique. Emulsion formation in different shear rate conditions was used to optimize the size of the carriers. The prepared microspheres were observed under an inverted optical microscope which confirmed their micrometric size. The nanospheres were analyzed by atomic force microscopy, which allowed visualization of their shape and measurement of their size. Moreover the hydrodynamic diameter of the nanospheres, polydispersity index as well as zeta potential were examined by dynamic light scattering. The experiments show that drug release does not depend on the size of the carriers. Analyzed carriers do not cause cytotoxicity upon contact with osteoblast like-cells.

17

Kyphosis correction after vertebroplasty in osteoporotic vertebral compression fractures

Dragan Sz.F., Urbański W., Żywirski B., Krawczyk A., Kulej M., Dragan Sz.Ł.

Acta of Bioengineering and Biomechanics

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2012

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Vol. 14, no. 4

63-69

EN

Percutaneous vertebroplasty is a minimally invasive method of treating vertebral compression fractures aimed mainly at reduction of pain. It has been observed that fractured vertebral bodies filled in with cement might also influence the increase of their height and thus lead to reduction of post-traumatic spine kyphosis. The aim of the research was to assess the possibility of reducing the kyphotic deformation of operated spine through kyphosis measurement of vertebras adjacent to fracture. 24 patients underwent percutaneous vertebroplasty on account of compression fracture of 40 vertebral bodies in thoracic and lumbar regions. On digital x-ray spine images taken in patients before and after surgery the angle of kyphosis or lordosis of bodies above and below the fractured vertebra was measured with the use of the Cobb method. Vertebroplasty in the material examined caused reduction of kyphosis in 33 cases (80.48%) and correction by 5.78 degrees on average. No regularity was found either between the occurrence of correction (and its level) and operated spine region or between the possibility of kyphosis correction and time that passed between fracture and surgery.

18

Correlations between structural and mechanical properties of human trabecular femur bone

Nikodem A.

Acta of Bioengineering and Biomechanics

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2012

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Vol. 14, no. 2

37-46

EN

In this article, the author presents mathematical relationships between the structural and mechanical properties of cancellous human bone tissue obtained by experimental analysis of specimens. Bone tissue material can adjust its internal structure to the existing loading conditions. The mechanical properties affect the structural properties but changes in structural properties likewise cause changes in the mechanical properties of the tissue. In normal tissue, the processes of tissue construction, destruction, and reconstruction are mutually balanced and complementary; if that balance is disturbed, lesions can occur. Therefore, normal bone tissue and pathologically changed tissue (osteoporosis and osteoarthrosis) coming from the area of human femoral head were examined. The structural properties of cancellous tissue specimens were determined non-destructively for three-dimensional reconstructions with the use of modern micro-CT methods. The mechanical properties of the specimens were determined by an uniaxial compression test in three orthogonal directions. Next, in order to specify the compressive strength, a failure test was conducted in the direction perpendicular to the neck-shaft angle of the hip joint.

19

Computer aided diagnostic of risky state in human pelvic bone

John A., Wysota P.

Journal of Achievements in Materials and Manufacturing Engineering

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2011

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Vol. 49, nr 2

313--322

EN

Purpose: of this paper is to raise the issue of recognition of dangerous states in human pelvic bone. These states can lead to damages of bone. Design/methodology/approach: consist of using the images from quantitative computed tomography (QCT). On the base of obtained data the numerical model of pelvic bone was created. Very important stage it was determination the values of material parameters. In the paper two methods were described. The first method directly basis on the data from radiology. In regard to difficulties with tomography data the second method was applied - the numerical simulations. The computer program was developed to obtain distribution of material parameters in numerical model of pelvic bone on the base of decreasing of bone mass. Findings: of the paper is that when decreasing of bone mass occurs in whole bone the stresses grow up continuously at the time. When decreasing of bone mass appears in individual region only the stresses decrease at the beginning and next increase while the bone mass still decrease. It could be one of the reason of lack of the symptoms in primary stage of osteoporosis. Research limitations/implications: are connected with accessibility of data from QCT. During QCT the bone system as well as density phantom are X-rayed simultaneously. On the base of standard density coming from the phantom the calibration curve is drown. Practical implications: it is the proposed procedure which facilitate the detection of risky state in pelvic bone. Originality/value: of researches consist in complex approach to problem of osteoporosis in human pelvic bone and applying the numerical simulations to create the numerical model of pelvic bone with osteoporotical changes.

20

Zastosowanie elektrochemicznej spektroskopii impedancji w badaniach korozji klamer NiTi użytych w osteosyntezie złamań kości twarzy

Łosiewicz B., Lekston Z., Prusik K., Winiarski A., Jędrusik-Pawłowska M.

Engineering of Biomaterials

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2011

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Vol. 14, no. 106-108

44--49