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Biomechanical influences on head posture and the respiratory movements of the chest

Szczygieł E., Węglarz K., Piotrowski K., Mazur T., Miętel S., Golec J.

Acta of Bioengineering and Biomechanics

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2015

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Vol. 17, no. 2

143--148

EN

Purpose. The head represents 6% of total body weight, therefore it can significantly affect the biomechanics of human posture control, movements and activities. When set out of vertical body axis, head position interferes with the work of the other links in the kinematic chain. The aim of our study was to evaluate the effect of head posture on the breathing activities of the chest. Material and methods: The research was conducted on a group of 65 patients (51 years ± 9.8 years), including 48 women and 17 men. Head posture and chest movements were assessed using a photogrammetric method. Results: The results confirmed the existence of a negative correlation between head position in the sagittal plane and movements of lower ribs. Forward head posture resulted in lower amplitude of costal arch motion: for the transverse plane Spearman’s R = –0.296, for the frontal plane; –0.273, –0.289. Tilting the head in the frontal plane also influenced the change in the biomechanics of breathing and contributed to a reduction of respiratory movements of the lower ribs Spearman’s R = –0.260. Conclusions: Changing the position of the head causes disturbances in the three-dimensional shape of the chest and its respiratory movements.

2

Influence of the front part of the vehicle and cyclist’s sitting position on the severity of head injury in side collision

Fanta O., Boucek J., Hadraba D., Jelen K.

Acta of Bioengineering and Biomechanics

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2013

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Vol. 15, no. 1

105--112

EN

An injury of cyclists during a collision with a car is currently a neglected topic. Most research projects evaluate in detail the injury of pedestrians, but with an increasing number of cyclists it will be necessary to devote more attention to their safety. This study is focused on the most common type of collision and offers insights into the biomechanics of cyclist’s head injury without the use of bicycle helmet. Initial mechanical and kinematic conditions that affect Head Injury Criterion (HIC) after a car hits a cyclist were determined using simulation software MADYMO. In relation to HIC, three different shapes of the front part of the car and three basic cyclist’s positions were compared.

3

Próba oceny urazu głowy w ochronie balistycznej miękkiej

Jamroziak K.

Modelowanie Inżynierskie

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2011

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T. 11, nr 42

179-190

PL

W artykule poprzez analizę literatury omówiono główne problemy związane z kryterium urazu głowy. Przeprowadzono testy balistyczne ostrzelania hełmu kompozytowego, rejestrując wybrane wartości. Dokonując oceny wyników eksperymentalnych i danych zawartych w normach oraz literatury, sformułowano wnioski i kierunki dalszych prac.

EN

The paper presents main issues regarding a head injury criterion, based on an analysis of available publications. After conducting ballistic tests, i.e. firing at composite helmet, the specific data was registered. An examination of test results, as well as data from both regulations and literature, resulted in a formulation of conclusions and marked out further research.

4

An ellipsoidal model for studying response of head impacts

Heydari M., Jani S.

Acta of Bioengineering and Biomechanics

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2010

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Vol. 12, no. 1

47-53

EN

The objective of this study was to propose a new analytical model for studying response of head impacts. Head is modeled by fluidfilled ellipsoidal shell of inconstant thickness impacted by a solid elastic sphere. Modeling the head as an ellipsoid is more realistic than modeling it as a sphere, the previous model existing in the literature [3]–[8]. In this model, the effect of Hertzian contact stiffness and local shell stiffness are combined to derive explicit equations for impact duration, the peak force transmitted to head, and the head injury criterion. One of the advantages of the model presented is sensitivity to the site of impact. A comparison between the present analytical results with the analytical data from spherical model [8] has been done to verify the validation of the present model.

5

Interdisciplinary researches supporting neurosurgical correction of children head deformation

Gzik M., Wolański W., Tejszerska D., Gzik-Zroska Β., Koźlak Μ., Larysz D.

Modelling and Optimization of Physical Systems

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2009

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z. 8

49--54

EN

The researches supporting neurosurgical correction of children head deformations are presented in this páper. On the basis of Computer tomography CT two models were created. Seans helped to generate two models of craniosynostoses: first scaphocephaly and second trigonocephaly. Three-dimensional models of deformed skuli were created with use of Mimics software. The models were transformed to FEM and used for suitable shape bone determination. Material properties of modelled bones were assumed on the basis of experimental researches. The geometrical models were presented in 3-dimensional Virtual reality.

PL

W pracy przedstawiono badania wspomagające zabiegi chirurgicznej korekcji deformacji główki dziecka. Na podstawie tomografii komputerowej opracowano dwa modele zniekształconych główek z scaphocephalią i trigonocephalią. Trójwymiarowe modele zniekształconych główek zostały opracowane przy użyciu programu Mimics. Następnie modele zostały dyskretyzowane i posłużyły do określania poprawnych kształtów. Własności materiałowe modeli zostały przyjęte z badań eksperymentalnych, a wyniki modelowe przedstawiono w trójwymiarowej rzeczywistości wirtualnej.

6

Zakres błędu w ustawieniu głowy przy powrocie do pozycji referencyjnej

Nowak K., Drużbicka A., Wdowik A., Sobota G.

Aktualne Problemy Biomechaniki

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2009

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z. 3

173--176

PL

Celem niniejszej pracy było sprawdzenie, czy podczas wykonywania zadania ruchowego z pozycji wyjściowej, powrót do pozycji końcowej wykonywany jest w to samo miejsce. Zaobserwowano, iż po każdym powrocie z rotacji do pozycji wyjściowej ustawienie głowy różniło się od położenia referencyjnego, ustalonego na początku badania przed wykonywaniem zadania. Zostało to określone mianem błędu, którego średnia wartość wynosiła 3,48 stopnia kątowego ±2,135.

EN

The aim of the study was to check evaluate if during the performance of the exercise from the starting position, the return would be into the same position. It has been observed that after every rotation to the starting position, a head’s position was different from the referential position which was set up at the beginning of each examination before the exercise was performed. It has been referred to as an error of average value of 3,48 of (2,135) angular degree ±2,135.

7

Inżynierskie metody wspomagania leczenia deformacji główki dziecka

Gzik M., Wolański W., Tejszerska D., Lichograj P., Larysz D.

Aktualne Problemy Biomechaniki

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2009

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z. 3

127--130

PL

W referacie przedstawione zostały badania modelowe dotyczące korekcji patologicznego ukształtowania głowy u dzieci. Wykorzystując program Mimics 11 Materialise sformułowano model bryłowy zdeformowanej czaszki dziecka w oparciu o zdjęcia tomografii komputerowej TK. W kolejnym etapie przeprowadzono analizę numeryczną w środowisku programu ANSYS w celu określenia stanu naprężeń i odkształceń wynikających z przyłożonych sił zewnętrznych. Badania mają charakter interdyscyplinarny są realizowane we współpracy inżynierów i lekarzy oddziału neurochirurgii dziecięcej.

EN

Modelling researches of pathological children head deformation correction are presented in this paper. With use of Mimics 11 Materialise software solid model of analysed example were created on the basis of computer tomography scans. Next the model was imported to ANSYS program in order to estimate correlation between external forces and head deformation. The research has interdisciplinary character as cooperation between engineers and neurosurgeons.

8

Motion analysis of upper parts of human body under dynamical loading

Gzik M., Tejszerska D.

Zeszyty Naukowe Katedry Mechaniki Stosowanej / Politechnika Śląska

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2002

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z. 19

51-54

EN

The mathematical model of the head and seven cervical vertebrae describing dynamics during car collision is presented in this paper. Article included the numerical simulation data of dynamical forces into human cervical spine. On the basis this model is creating extended model included movable trunk and taking into consideration contact human body with armchair, wheel and seat belts.