Wyniki wyszukiwania - Biblioteka Nauki

1

Analiza biomechaniczna stentów urologicznych

100%

Kajzer W. , Marciniak J.

Inżynieria Biomateriałów

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2005

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tom R. 8, nr 47-53

141--143

2

Biomechanical analysis of plates used in treatment of pectus excavatum

80%

Krauze A. , Marciniak J. , Marchacz A.

Archives of Materials Science and Engineering

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2007

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tom Vol. 28, nr 5

301-304

EN

Purpose: The paper presents computer simulation results of displacement, strain and stresses in the plate used in treatment of the pectus excavatum. Design/methodology/approach: The numerical analysis was performed for selected models of the stabilizing plates made of the Cr-Ni-Mo stainless steel (AISI 316L) and Ti-6Al-4V ELI alloy. Findings: The displacement, strain and stress analyses showed the diverse results depending on the plates geometry and the properties of the applied metallic biomaterial. The numerical analysis shows that stresses in plates didn't exceed the yield point: for the stainless steel R p0,2 min=690 MPa and Ti-6Al-4V ELI - Rp 0,2min =895 MPa. Research limitations/implications: The limitations were connected both with the necessity of simplifications applied to the numerical model and with the established boundary conditions. Practical implications: The obtained results are the basis for the stabilizing plate optimization to ensure favorable conditions for the pectus excavatum treatment. Originality/value: The work presents the displacement-strain-stress characteristics obtained on the basis of the numerical analysis.

3

Experimental and numerical analysis of urological stents

80%

Kajzer W. , Marciniak J.

Archives of Materials Science and Engineering

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2007

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tom Vol. 28, nr 5

297-300

EN

Purpose: In order to evaluate the characteristic changes of the stents' diameters in function of the elongation (during elastic expansion) the biomechanical tests were carried out. The numerical analysis of the selected forms of urological stents was performed. The numerical results were compared with the experimental ones. Design/methodology/approach: The urethral stent commonly used in clinical practice was analyzed. Two types of research were carried out: experimental-in order to determine the displacement characteristic of the stent, and numerical (by means of the finite element method)-in order to evaluate stresses and strains in the stent. Findings: The comperative analysis of the obtained experimantal and numerical results showed good correlation, that proves the proper selection of the modeling conditions, and boundary conditions adequate to the real object. Research limitations/implications: The limitations were connected with the necessity of simplifications applied to the numerical model of the urological stent, and also with the difficulties caused by the established boundary conditions. Practical implications: The self-expanding stents analyzed in the work are implants for which the change of the diameter causes the significant change of the length. Due to the fact, the very important issue during implantation of this type of stent is the appropriate positioning in the narrowed part of urethra. The worked out characteristics allows to determine the length of the implant for the given diameter. Originality/value: The work presents the dispacement characteristics of the stent obtained on the basis of the experimental and numerical tests. The correlation of the obtained results is also presented.

4

Numerical analysis of femur in living and dead phase

80%

Krauze A. , Kaczmarek M. , Marciniak J.

Journal of Achievements in Materials and Manufacturing Engineering

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2008

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tom Vol. 26, nr 2

163-166

EN

Purpose: The paper presents numerical analysis results of stresses and displacement in femur in a living and a dead phase. The aim of the work was to present the influence of different mechanical properties of bone tissue on the obtained results. The appropriate selection of the properties ensures correct results, comparable with the results obtained in real conditions. Design/methodology/approach: The analysis was carried out on the femur of adult. The influence of the selected properties on the results of numerical analyses was analyzed. In order to carry out calculations, 3 models of diverse mechanical properties (Young modulus of bone in a living phase EI=17260 MPa, Young modulus in order to carry out a comparison analysis EII=18600 MPa and Young modulus of bone in a dead phase EIII=20202 MPa) were selected. Findings: The analyses showed the difference in displacements and reduced stresses depending on the selected mechanical properties. The analyses show that in order to select the appropriate stabilization method, mechanical characteristics of bone structures should be considered as viscoelastic. Quality of bone structures depends on individual features (genetic, hormonal, metabolic and circulatory factors). Research limitations/implications: The limitations were connected with simplification of numerical model of femur as well as with the selected boundary conditions. Practical implications: The obtained results can be useful in clinical practice. They can be applied in selection of stabilization methods or rehabilitation as well as in describing the biomechanical conditions connected with type of bone fracture obtained from medical imaging. Originality/value: Stress-displacement characteristics of femur for different degrees of demineralization, obtained from the numerical analyses were presented in the work.

5

Porównawcza analiza biomechaniczna wybranych systemów stabilizacji transpedikularnej

80%

Sajewicz E. , Koronkiewicz T. , Sidun J.

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tom Vol. 2, no. 1

69-72

PL

Prezentowane w pracy wyniki dają odpowiedź na pytanie dotyczące wpływu podatności lędźwiowego odcinka kręgosłupa na jakość stabilizacji transpedikularnej. Przedstawiono wyniki badań przemieszczeń odcinka lędźwiowego kręgosłupa poddanego jednocześnie kompresji i zginaniu (mimośrodowe ściskanie). Badano przemieszczenia kręgu L3 dziewięciu preparatów ustabilizowanych za pomocą systemów Socon, Omega oraz Bial-Stab, a następnie pomiary powtarzano po wykonaniu korporektomii na poziomie L3. Wyniki badań porównywano z wynikami uzyskanymi na preparatach nieustabilizowanych. Wykazano, że brak ciągłości przedniej kolumny kręgosłupa nie wpływa na biomechaniczną jakość stabilizacji w zakresie stosowanych obciążeń. Wyniki analizy statystycznej jednoznacznie wskazują, że podatność kręgosłupa na obciążenia wpływa w sposób istotny na wartości przemieszczeń po stabilizacji przeznasadowej. Nie zaobserwowano istotnych statystycznie różnic w jakości stabilizacji pomiędzy poszczególnymi systemami.

EN

In the paper the results of influence of lumbar spine flexibility on quality of transpedicular stabilization are presented. In particular, measurements of displacements of the lumbar spine subjected to simultaneous compression and bending (eccentric compression) are shown. The displacements were measured at L3 level in nine lumbar specimens stabilized by means of Socon, Omega and Bial-Stab systems. The obtained results were compared with the results of measurements carried out on the specimens without stabilization. It was also shown that a lack of continuity of the anterior column did not influence on quality of the stabilizations in the range of the used loading. The statistical analysis showed that lumbar flexibility sufficiently influenced on the displacements of the fixed lumbar spine. No statistical differences were observed between of the systems used as regards their biomechanical performance.

6

Expandable intramedullary nail – experimental biomechanical evaluation

60%

Kajzer A. , Kajzer W. , Marciniak J.

Archives of Materials Science and Engineering

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2010

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tom Vol. 41, nr 1

45-52

EN

Purpose: The paper presents results of experimental analysis of femur and femur - expandable intramedullary nail system. The aim of the work was to determine displacement in three models. In addition, the torsion of the system aiming at determining the moments depending on the torsional angle of the bone was carried out. Design/methodology/approach: Three femurs were selected for studies. The analysis was carried out on the femur - expandable intramedullary nail system. The influence of the loads and displacements on the bone - nail system on the results of experimental analysis was analysed. In order to carry out calculations, three models were selected: model I - bone without fracture gap, model II and III - femur with expansion intramedullary nails - fracture gap was located 100 mm under greater trochanter. The studies were performed on femur models produced by Swedish company Sawbones. The intramedullary "Fixion IM" nails (Ti-6Al-4V alloy) were implanted into the bone. Displacements of determinated models were being recorded from the sensors every 100 N from 10 N to 2000 N. Findings: The analyses showed the difference in displacements, depending on the selected models. Research limitations/implications: The limitations were connected with simplification of boundary conditions during analysis which were the result of the simplification of the models. While studying, muscles and ligaments supporting the bone in anatomic position were not taken into consideration. Instead, the system has been loaded with the axial force (compression). Practical implications: The obtained results can be useful in clinical practice. They can be applied in selection of stabilization methods or rehabilitation as well as in describing the biomechanical conditions connected with type of bone fracture obtained from medical imaging. Originality/value: . The work compares the values of displacement of characteristic points of femur (healthy - model I) with the femur - expandable intramedullary nail system (models II and III) with the applied force. In order to estimate the value of the torsional angle of the upper part in relation to the lower one depending on the applied force, the torsion of the model was conducted. On this basis, it was indicated a maximum moment in which the nail would not become loose in medullar canal.

7

Differences in male and female lower extremity joint kinematics during walking

60%

Szymańska K. , Domżalski M. , Stolarczyk A.

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2019

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tom 23(3)

39-46

PL

Wprowadzenie: Sposób chodu kobiet i mężczyzn jest od dawna postrzegany jako różny, jednak stosunkowo niedługo istnieje możliwość wykonania dokładnych pomiarów dających precyzyjne informacje na temat tych różnic. Stworzenie oddzielnych przedziałów norm chodu dla kobiet i mężczyzn mogłoby pomóc w diagnostyce, profilaktyce i terapii zaburzeń lokomocji. Cel: Praca przedstawia przegląd dostępnej literatury na temat chodu zdrowych dorosłych kobiet i mężczyzn, w celu wykazania czy istnieją naukowe podstawy do stworzenia oddzielnych przedziałów wartości norm dla chodu w zależności od płci. Metody: Przeszukano elektroniczne bazy danych PubMed, Web of Science i Science Direct stosując hasła ‚gait’, ‚sex’, ‚gender’, ‚men’, ‚women’, ‚male’, ‚female’. Kryteria włączenia obejmowały: artykuł był dostępny w języku angielskim, artykuł zawierał informacje dotyczące osób zdrowych, w badaniu analizowano biomechanikę chodu, w badaniu porównywano wartości dla obu płci, badanie obejmowało osoby dorosłe. Jeżeli w piśmiennictwie wyszukanych prac pojawiały się artykuły spełniające kryteria włączenia były one dołączane do przeglądu. Wyniki: Kryteria włączenia spełniało 12 prac. Po przejrzeniu abstraktów, a następnie pełnych tekstów pozostawiono 8 prac, 4 wyłączono ze względu na nie stosowanie powszechnych parametrów biomechanicznych lub badanie biomechaniki chodu do celów innych niż temat przeglądu (badanie ortez). Wnioski: Istnieją różnice w parametrach kinematycznych kobiet i mężczyzn podczas chodu dla miednicy i stawu biodrowego w płaszczyźnie czołowej i prawdopodobnie w płaszczyźnie strzałkowej dla stawu skokowego. Zalecane jest stworzenie oddzielnych przedziałów norm dla kobiet i mężczyzn.

EN

Introduction: Men and women are claimed to walk differently- with modern techniques we are able to quantify gait parameters and establish whether those perceived dissimilarities are supported by precise measurements. Creating separate normative values for men and women may help in gait disturbances diagnosis, prevention and therapy. Objectives: We review available studies on normal locomotion in adult men and women, to clarify if there is scientific evidence to create separate normative values of normal gait according to gender. Methods: Potentially relevant articles were identified with an electronic search of PubMed, Web of Science and Science Direct. Combination of keywords ‘gait’, ‘sex’, ‘gender’, ‘men’, ‘women’, ‘male’, ‘female’ were used. Articles were included if they met following criteria: article was written in English, the article contained information about non-pathological subjects, the study analyzed biomechanics of walking, the article compared metrics of both sexes, the study included data for adults. If additional papers were identified from cited references and met the inclusion criteria they were incorporated into the catalog of references. Results: The inclusion criteria was met by 12 articles. After reviewing abstracts and full-text articles 8 were included and 4 were excluded due to not applying common gait biomechanics parameters or studying gait biomechanics for purposes not connected to the review’s topic. Conclusions: There are differences between males’ and females’ gait kinematic values for coronal plane pelvis and hip movement and possibly in sagittal plane ankle movement. Creating separate normative values is recommended.

8

FEM used in improvement of quality of medical devices

60%

Ziębowicz B. , Ziębowicz A. , Szkodny J.

Journal of Achievements in Materials and Manufacturing Engineering

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2010

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tom Vol. 41, nr 1-2

172-179

EN

Purpose: The fundamental aim of this research was to determine the biomechanical characteristics of the medical bed made of carbon steel and an assessment of its stability. To define the biomechanical characteristics of the bed design, the finite element method (FEM) was applied. Additionally, the risk analysis was conducted according to the directives of ISO 14971 standard. Design/methodology/approach: The research was carried out on the typical rehabilitation bed. To define the biomechanical characteristics of this equipment, the finite element method was applied. Geometric model of medical bed, was discretized by means of SOLID 95 element. Appropriate boundary conditions imitating phenomena in the real system with appropriate accuracy were established. The aim of biomechanical analysis was calculation of displacements and stresses in the bed’s construction elements in a function of the applied loading. In order to carry out calculations, 3 models of diverse variants of loading were selected – safe working load - model 1, transverse stability - model 2 and longitudinal stability - model 3. Findings: The analyses showed the difference in displacements, strains and stresses in the characteristic points depending on the selected loading. That also helped to determine maximal loading causing the exceeding of the yield stress of the bed’s components. Research limitations/implications: The limitations were connected with simplification of numerical model of femur as well as with the selected boundary conditions. Practical implications: The obtained results can be useful in the designing process (modification of requirements regarding design and construction, as well as materials used in the production of the device, and reduction of risk as far as possible to the patient). They prove that 3D geometrical analysis works quite well for assistive medical devices design. Originality/value: Stress-strain-displacement characteristics of the medical bed’s elements, obtained from the numerical analysis were presented in the work.

9

A Biomechanical Analysis of Manual Lifting Tasks Performed in Restricted Workspaces

60%

Elfeituri F. E.

International Journal of Occupational Safety and Ergonomics

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2001

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tom Vol. 7, No. 3

333--346

EN

This paper describes the results of an experimental study aimed at evaluating the biomechanical effects of working in a spatially restricted environment on manual lifting tasks. The main objective of the study is to estimate the biomechanical loading (in terms of peak compression and shear forces) on the lumbar spine for the selected combinations of limited headroom heights and twisting angles. A three-dimensional dynamic biomechanical model was utilized to assess peak compression and shear forces at the L5/S1 lumbosacral joint. The results indicated that by reducing the headroom height, the participants were forced to stand with their trunks fully flexed forward which, by increasing the mechanical disadvantage at the lumbosacral disc, increased the compression forces. Both compression and shear forces were affected by the increase in twisting angle. The greater the twisting angle, the higher the compression and shear forces. Regression models were developed and validated, which demonstrated high accuracy of predicting the psychophysical and biomechanical lifting capacities.

10

FEM analysis of compression screws used for small bone treatment

60%

Kajzer W. , Kajzer A. , Marciniak J.

Journal of Achievements in Materials and Manufacturing Engineering

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2009

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tom Vol. 33, nr 2

189-196

EN

Purpose: The paper presents results of numerical analysis in metatarsal bone „I” - compression screws system. The aim of the work was determined stresses, strain and displacement in the inserted screws. Design/methodology/approach: Metatarsal bone „I” was selected to researches. The analysis was carried out on the metatarsal bone „I” - compression screws system. The influence of the loads and displacements on the bone - screws system on the results of numerical analyses was analyzed. In order to carry out calculations, 2 models of diverse mechanical properties of screw - Ti-6Al-4V alloy - model 1, stainless steel (Cr-Ni-Mo) - model 2 and two load steps were selected. Findings: The analyses showed the difference in displacements, strains and stresses depending on the selected mechanical properties screws and the way of loads. Research limitations/implications: The limitations were connected with simplification of numerical model of femur as well as with the selected boundary conditions. Two difference way of loads metatarsal bone „I” - compression screws system: 1_force F = 500 N, 2_ displacement l = 1 mm were applied. Practical implications: The obtained results can be useful in clinical practice. They can be applied in selection of stabilization methods or rehabilitation as well as in describing the biomechanical conditions connected with type of bone fracture obtained from medical imaging. Originality/value: Stress-strain-displacement characteristics of metatarsal bone „I” - compression screws system, obtained from the numerical analysis were presented in the work.

11

Analiza biomechaniczna ryglowanego zespolenia śródszpikowego kości udowej

60%

Kajzer W. , Kajzer A. , Szewczenko J. , Marciniak J.

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2010

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tom Vol. 13, no. 96-98

54--57

12

Analiza biomechaniczna zespolenia kość śródstopia I - śruby dwuwchodowe

60%

Ziębowicz A. , Kajzer A. , Kajzer W. , Marciniak J.

Engineering of Biomaterials

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2009

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tom Vol. 12, no. 89-91

249--251

13

FEM analysis of expandable intramedullary nails in healthy and osteoporotic femur

51%

Kajzer W. , Kajzer A. , Marciniak J.

Journal of Achievements in Materials and Manufacturing Engineering

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2009

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tom Vol. 37, nr 2

563-570

EN

Purpose: The paper presents the results of numerical analysis of expandable intramedullary nail – femur system in different states of healing. The aim of the research was to determine displacements, deformations and stresses occurring in a bone depending on the age of the patient and the extent level of osteoporosis. Design/methodology/approach: A femur was selected to numerical analysis. The analysis concerned the influence of the load and torsion of the system on the obtained results of displacements, deformations and reduced stresses. In order to make calculations, four models with different mechanical properties were chosen: model 1: femur with mechanical properties corresponding with a femur of a patient at the age of 16, model 2: with mechanical properties corresponding with a femur of a patient at the age of about 28, model 3: with mechanical properties corresponding with a femur of a patient at the age of about 20 and at the age of 50 to 65 years old and model 4: with mechanical properties corresponding with a femur of a patient at the age above 70 or with osteoporosis. For the chosen model of intramedullary nail, mechanical properties of titan alloy Ti-6Al-4V were used. Two load steps were analyzed: load step 1 in which simple axial load with a value ranging from 250 up to 1000 N simulating patient standing on one leg was used, and load step 2 – a torsion analyzing loads that the nail is exposed to while walking. Findings: Conducted analysis of the system showed the difference in displacements, deformations and reduced stresses depending on assumed mechanical properties of femur and load step of the system. Research limitations/implications: The limitations were connected with the necessity of simplifying the assumptions, which were associated with limitations caused by boundary conditions. In researches 4 forces loading the femur axially were used: 1: force F = 250N, 2: with force F = 500N, 3: with force F= 750N and 4: with force F = 1000N and 5 values of angle displacement of the femur head were assumed: 1: angle displacement ö = 1°, 2: ö = 5°, 3: ö = 10°, 4: ö = 15°, 5: ö = 20°. Practical implications: Obtained results can be applied in selection of stabilization methods of bone fragments and in forecasting biomechanical conditions depending on the age of patient and the state of his general conditions of bones. Originality/value: The paper presents the displacement-deformation-stress characteristics of femur - expandable intramedullary nail system, using the Finite Elements Method (FEM) in the analysis.

14

Biomechaniczna analiza wchodzenia na schody oraz badania stabilograficzne pacjentów z zaburzeniami neurologicznymi

51%

Tejszerska D. , Michnik R. , Jurkojc J. , Guzik-Kopyto A. , Michalik K. , Kmiotek A. , Rycerski W.

Aktualne Problemy Biomechaniki

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2010

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tom z. 4

249--254

PL

W pracy przedstawiono biomechaniczną analizę wchodzenia po schodach oraz badania stabilograficzne pacjentów ze schorzeniami neurologicznymi. W badaniach analizowano kinematykę oraz wartości sił reakcji podłoża podczas wchodzenia po schodach. Wielkości kinematyczne wyznaczono za pomocą systemu APAS. Pomiarów sił reakcji podłoża dokonano za pomocą platform dynamometrycznych firmy Kistler. Badania doświadczalne objęły grupę 8 osób z zaburzeniami neurologicznymi. Badania zrealizowano w Górnośląskim Centrum Rehabilitacji w Reptach.

EN

Biomechanical analysis of climbing the stairs and stability of patients having neurological disorders is presented in the paper. Analysis of kinematics and ground reactions was carried out for climbing the stairs. Kinematic quantities were determined by means of the APAS system. Ground reactions were measured with the use of the Kistler platform. Eight patients took part in the research. All measurements were carried out in the Silesian Center of Rehabilitation “Repty”.

15

Numerical and experimental analysis of spine’s transpedicular stabilizer

51%

Kiel M. , Marciniak J. , Basiaga M. , Szewczenko J. , Kus W. , Kokot G. , Wadek T.

Journal of Achievements in Materials and Manufacturing Engineering

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2010

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tom Vol. 41, nr 1-2

124-130

EN

Purpose: The aim of the work was a numerical and experimental analysis of spine’s transpedicular stabilizer on lumbar part of spine. The result of the analysis was determination of displacements of the stabilizers’ elements. Design/methodology/approach: To define numerical characteristic of the lumbar spine – transpedicular spine stabilizer system, the finite element method was applied. Geometrical models of lumbar part of spine and transpedicular stabilizer were discretized by SOLID95 element. The boundary conditions imitating phenomena in real system with appropriate accuracy were established. The experimental analysis was carried out for spine’s transpedicular stabilizers which were implanted on lumbar part of pig spine. The analysis was realized by means of testing machine MTS Insight with the use of videoextensometer. Numerical and experimental analysis were carried out for stabilizer made of stainless steel Cr-Ni-Mo. System was loaded by uniaxial compression with forces from 50 N to 1600 N. Findings: The result of analysis was calculation of relative displacements of the transpedicular stabilizer in a function of the applied loading; F = 700 - 1600 N for numerical model and F = 50 - 1600 N for experimental model. Research limitations/implications: The results of numerical analysis for transpedicular stabilizer obtained by finite element method were used to determine a construction features of the stabilizer, and to select mechanical properties of metallic biomaterial. The calculation of displacements for stabilizer show that the proposed type of stabilizer enables correct stabilization of spine. Practical implications: Both results of numerical and experimental analysis showed correct selection of mechanical properties of metallic biomaterial which were used to made the proposed type of transpedicular stabilizer. Originality/value: Advantageous results of analysis showed that the type of stabilizer may be used in clinical practice.

16

Analiza biomechaniczna układu wiertło chirurgiczne - kość udowa

51%

Paszenda Z. , Basiaga M.

Aktualne Problemy Biomechaniki

|

2009

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tom z. 3

181--186

PL

Zasadniczym celem prezentowanej pracy była analiza biomechaniczna układu wiertło chirurgiczne - kość udowa w warunkach symulujących proces wiercenia w kości. Opracowano model geometryczny wiertła chirurgicznego o zróżnicowanej geometrii ostrza (2κ1 = 90° i 2κ2 = 120°) oraz krążka symulującego kość udową. Obliczenia przeprowadzono dla wiertła wykonanego ze stali X39Cr13. Efektem zrealizowanej analizy było wyznaczenie stanu odkształceń i naprężeń zredukowanych w części roboczej wiertła w funkcji obciążenia siłą F = 20-100 N i prędkością obrotową n = 2000 obr/min.

EN

The aim of the work was determination of biomechanical analysis of a surgical drill - bone system in simulated conditions of drilling in a bone. Geometrical models of the surgical drill of diverse geometry of the edge (2κ1 = 90° and 2κ2 = 120°) and the disc simulating femur were worked out. Calculations were carried out for the drill made of martensitic Steel (X39Cr13). The effect of numerical analysis was determination of strains and stresses in working part of the drill as a functional of the applied loading F = 20-100 N and rotational speed n = 2000 rpm.

17

Analiza biomechaniczna obciążenia w kończynie dolnej podczas jazdy konnej

51%

Sobuś M. , Iwaniec M. , Frontczak A. , Łagan S.

Aktualne Problemy Biomechaniki

|

2011

|

tom z. 5

137--142

PL

W niniejszym referacie podjęto próbę analizy wpływu długości strzemion w jeździe konnej na obciążenia powstające w kończynie dolnej. Wraz ze zmianą długości strzemion zmienia się kąt zgięcia nogi w stawie kolanowym oraz skokowym.

EN

In this publication we would like to analyse how length of the stirrups effects on loads in the lower limb. The longer stirrups are the bigger knee and ankle angles are. In horse riding there are some kinds of rider‟s positions, which are connected with discipline. Dressage rider„s seat is different than jumping or race seat, so we would like to analyse these differences. For example the long stirrups of the dressage rider allow for a long leg. But the short stirrups of a jockey allow the rider to stay over the galloping horse's center of balance and allow the horse to reach the maximum possible speed.

18

Biomechaniczna analiza wypadku samochodowego z zastosowaniem urządzenia typu HANS podpierającego głowę oraz odcinek szyjny kręgosłupa kierowcy

51%

Burkacki M. , Joszko K. , Gzik M.

Aktualne Problemy Biomechaniki

|

2013

|

tom z. 7

17--22

PL

Celem pracy było dokonanie analizy w środowisku MADYMO wypadku samochodu rajdowego z zastosowaniem urządzenia HANS podpierającego głowę oraz odcinek szyjny kręgosłupa kierowcy. Stworzono model odzwierciedlający warunki panujące w samochodzie rajdowym, który został użyty do symulacji zderzenia przy przyspieszeniu 45G. Na podstawie otrzymanych wyników można stwierdzić, iż system HANS ogranicza urazowość głowy oraz odcinka szyjnego kręgosłupa podczas wypadku. Wpływa on na zmniejszenie siły działającej na odcinek szyjny kręgosłupa, ugięcie w odcinku szyjnym kręgosłupa oraz ugięcie klatki piersiowej.

EN

The aim of this study was to analyze a rally car accident in MADYMO software with use of the HANS device supporting head and cervical spine of the driver. Created model reflects the construction and equipment of a rally car which was used to simulate a 45G accident. Based on the results it can be said that the HANS system reduces trauma of the head and cervical spine during accident. It also reduces force affecting cervical spine, deflection of the cervical spine and chest deflection.

19

Evaluation of Low Back Pain Risks in a Beef Skinning Operation

51%

Das B. , Sengupta A. K.

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2000

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tom Vol. 6, No. 3

347--361

EN

The low back pain risks in a beef skinning operation at a high stand kill floor workstation was evaluated. The increases in compressive forces at lower back (L5/S1) between normal slump (back angle 25°, measured in the sagittal plane) and severe (45°) and between normal slump and very severe (70°) bent back postures were 387 N or 28% and 616 N or 45%, respectively. The high spine load coupled with high level of repetition can have a high probability of fatigue failure in the spine structural members. Non-neutral back posture for a large portion of the total work time can be a low back pain risk factor. The videotape analysis showed that the times involved during the task performance for the bent back (more than 25°) and severe bent back (more than 45°) were 48.4 and 33.5% of the total cycle time, respectively. The upper limit from OWAS (Ovako Working Posture Analysis System) for bent back posture is 30% of the total cycle time. The bent and twisted back posture (both more than 25°) time was 10.4% compared to OWAS limit of 5%. This indicated that actions are needed in the near future to alleviate the risk of low back pain. Ergonomics redesign of the workstation was recommended for the operation.

20

Biomechanical analysis of plate stabilization on cervical part of spine

51%

Kiel M. , Marciniak J. , Szewczenko J. , Basiaga M. , Wolański W.

Archives of Materials Science and Engineering

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2009

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tom Vol. 38, nr 1

41-47

EN

Purpose: The main aim of the work was determination of biomechanical analysis of cervical spine – stabilizer system made of stainless steel (Cr-Ni-Mo) and Ti-6Al-4V alloy. Design/methodology/approach: To define biomechanical characteristic of the system the finite elements method (FEM) was applied. Geometric model of part of spine C5-C7 and stabilizer were discretized by SOLID95 element. Appropriate boundary conditions imitating phenomena in real system with appropriate accuracy were established. Findings: The result of biomechanical analysis was calculation of displacements and stresses in the vertebras and the stabilizer in a function of the applied loading: 50-300 N for the stabilizer made of stainless steel (Cr-Ni-Mo) and Ti-6Al-4V alloy. Research limitations/implications: The result of biomechanical analysis for plate stabilizer obtained by FEM can be use to determine a construction features of the stabilizer, and to select mechanical properties of metallic biomaterial and estimation of stabilization quality. The calculation of displacements for part C5-C7 show that the proposed type of stabilizer enables correct stabilization used to clinical apply. Practical implications: The results of biomechanical analysis showed correct mechanical properties used to made the plate stabilizer. Originality/value: The obtained numerical results should be verified in “in vitro” tests.