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A cadaveric study on the rate of strain-dependent behaviour of human anterior cruciate ligament

Marieswaran M., Sikidar Arnab, Rana Abhishek, Singh Dilpreet, Mansoori Nasim, Lalwani Sanjeev, Kalyanasundaram Dinesh

Acta of Bioengineering and Biomechanics

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2021

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Vol. 23, no. 1

45--57

EN

Purpose: Failure of anterior cruciate ligament often occurs in young sports personnel hampering their career. Such ACL ruptures are quite prevalent in sports such as soccer during dynamic loading which occurs at more than one rate of loading. In this work, a structural constitutive equation has been used to predict the forces acting on ACL for different rates of loading. Methods: Ligaments with distal femur and proximal tibia were subjected to tensile loading to avoid crushing of tissue ends and slipping at higher rates of strain. Custom designed cylindrical grippers were fabricated to clamp the distal femur and proximal tibial bony sections. To estimate parameters for the model, eighteen fresh cadaveric femur-ACL-tibia complex (FATC) samples were experimented on by pure tensile loading at three orders of rates of strain viz., 0.003, 0.03, and 0.3 s–1. The experimental force-elongation data was used to obtain parameters for De-Vita and Slaughter’s equation. The model was validated with additional tensile experiments. Results: Statistical analysis demonstrated failure stress, Young’s modulus and volumetric strain energy to vary significantly as a function of rate of strain. Midsection failure was observed only in samples tested at 0.03 s–1. Femoral or tibial insertion failure were observed in all other experiments irrespective of rate of strain. Conclusion: Human FATC samples were tensile tested to failure at three rates of strain using custom-designed cylindrical grippers. A structural model was used to model the data for the ACL behaviour in the linear region of loading to predict ligament behaviour during dynamic activities in live subjects.

2

Assessment of body balance of patients treated with the Ilizarov method for tibial nonunion

Pajchert-Kozłowska Andżelika, Pawik Łukasz, Szelerski Łukasz, Żarek Sławomir, Górski Radosław, Pawik Malwina, Fink-Lwow Felicja, Morasiewicz Piotr

Acta of Bioengineering and Biomechanics

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2020

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Vol. 22, no. 3

131--137

EN

Purpose: The biomechanics of the musculoskeletal system in patients after tibial nonunion treatment using the Ilizarov method have not yet been fully explored. From the orthopaedic and patient point of view, after the treatment, an assessment should be carried out of the biomechanics of the musculoskeletal system. The aim of this study was to assess the body balance of patients treated with the Ilizarov method for tibial nonunion. Methods: The research group included 24 individuals with a mean age of 55 years, who were treated for aseptic tibial nonunion with the Ilizarov method. The control group was matched to the study group in terms of gender and age, and consisted of 32 subjects with a mean age of 50.5 years and no significant medical history. This study evaluated the balance of patients with the use of pedobarography. Results: In the control group, a statistically significantly shorter path of centre of gravity was observed. There were no statistical differences between the study and control groups for the field area of the centre of gravity. There were no statistical differences between the study and control groups for the minor axis length or major axis length of the centre of gravity. There was a relationship between the centre of pressure path length and the age of the participants in both the control group and the study group. Conclusions: Treatment of patients with tibial nonunion with the Ilizarov fixator achieves similar balance to healthy volunteers. In the pedobarographic evaluation, patients treated for tibial nonunion using the Ilizarov method had similar statics of the musculoskeletal system to healthy volunteers.

3

Two medium-sized deinotheres (Proboscidea: Mammalia) from the Miocene rocks of the Eastern Carpathians Foreland (Romania)

Ţibuleac P.

Geological Quarterly

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2018

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Vol. 62, No. 3

669--684

EN

The paper summarizes the medium-sized deinothere records from Romania, improving the palaeontological data of two less-known specimens from the Eastern Carpathians Foreland. The area is famous primarily by the large deinothere of Găicena and Mânzaţi assigned to the “Deinotherium gigantissimum”. Later, several fossils of Deinotherium were documented, but they remained generally unknown, and the morphological and biometrical data were not engaged in the further deinothere comparisons. The most important specimen is a fragmentary right hemimandible with well-fossili zed m1-m2, housed in the “Ion Borcea” Natural History Museum of Bacău. The p3-p4 and m3 preserved only the roots; even there are not obvious reworking signs. Furthermore, a tibia sin. fragment were firstly added. The fossil remains were unearthed from the Late Bessarabian rocks (MN 9) near Drăgeşti (Bacău County). The second specimen represents an isolated M2 sin of Deinotherium giganteum stored at the Museum of Paleontology “Alexandru Ioan Cuza” University of laşi. It was collected from a microconglomerate bed (Early Bessarabian, ?MN 7-8-Mn 9) cropping out in the Pietrăria Hill Quarry (Deleni, laşi County). The age of fossil-bearing layers was accurately documented by several mollusc assemblages.

4

Biomechanical analysis of diversified screw arrangement on 11 holes locking compression plate considering time-varying properties of callus

Sepehri B., Taheri E., Ganji R.

Biocybernetics and Biomedical Engineering

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2014

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Vol. 34, no. 4

220--229

EN

The 11 holes locking compression plate (LCP) is a type of fixator which is currently used in orthopedic surgeries for fixing fractures of long bones. 8 styles of screw positioning on this plate are possible so each orthopedist may use one of them during operations. The aim of the current study was the analysis of diversified screw arrangement on the mentioned LCP for fixation of medial transverse fracture of tibia considering time- varying properties of bone callus in 16-weeks curing duration. Stress shielding effects were also considered. Finite element method using Mimics 10.01, Solid works 2012 and Abaqus 6.11-1 software have been applied. Modeling of bone was done based on computer tomography (CT) scan of human right tibia and four types of forces have been loaded on intact bone and the same was loaded on fixated fractured ones in 8 treatments of fixation. Stresses in bone, plate and screws, also gap or callus strains and stiffnesses in 5 terms of curing duration in all of the treatments have been investigated and compared together using new defined parameters. Finally the preferred treatment was concluded. Results of this study may be used by orthopedists in applying such a fixator for fixation of tibia and other fractured long bones.

5

Zastosowanie wyników pomiarów współrzędnościowych do procesów modelowania geometrii w systemach CAD, na przykładzie kości piszczelowej

Łagan S., Niesułowski A.

Aktualne Problemy Biomechaniki

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2007

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z. 1

131--138

PL

W pracy przedstawiono proces tworzenia geometrii kości długiej, przy zastosowaniu programu CATIA. Uzyskany model opracowano na podstawie pomiarów współrzędnościowych, przetworzonych wstępnie do postaci pliku formatu IGES. Przybliżono planowane zastosowania.

EN

The paper presents a way of creating geometry of long bone with applying CATIA software. The model was generated on the base of coordination measurements transformed firstly into IGES format file.

6

Geometrical modeling of knee joint including anatomic properties

Borkowski P., Sowiński T., Kwiatkowski K., Skalski K., Żabicka M., Polczyński M.

Zeszyty Naukowe Katedry Mechaniki Stosowanej / Politechnika Śląska

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2006

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z. 26

40-46

EN

Presently, CT is one of the most common and accessible methods of human internal structure research. Current programmes for tomographic data processing of data logged from tomography projection allow generation of three-dimensional images of organs. These reconstructions show that they are usually suitable for a precise preparation of surgical procedure operation planning, particularly in the case of joints. In the paper, basic methodology of that kind is shown on the example of a knee joint. The methodology leads to obtaining individual three dimensional models of large human joints. Analysis of tomographic data and creation of the three-dimensional model of the joint was conducted with use of MIMICS.

7

Stress analysis in tibia and fibula

Mrozowski J., Awrejcewicz J., Śmiałek R.

Vibrations in Physical Systems

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2002

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Vol. 20

230--231