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Kinematic analysis of L4–L5 spinal segment with spondylolysis and different types of grade 1 spondylolisthesis: a nonlinear finite element study

Yaroub Suhaib, Hamandi Sadiq J., Mohson Khaleel

Acta of Bioengineering and Biomechanics

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2022

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Vol. 24, no. 2

177--186

EN

This work aimed to evaluate and characterize the motion of the fourth and fifth lumbar vertebrae functional spinal unit with spondylolysis and different types of grade 1 spondylolisthesis using the finite element method. Methods: Nine nonlinear three-dimensional finite element models were reconstructed from computed tomography scans to five educational fourth and fifth lumbar vertebrae models. The intervertebral disc was simulated in two conditions: four models with healthy discs and five models with degenerated discs. Each model consisted of two vertebrae divided into three bony parts, two endplates, an intervertebral disc and five ligaments. The flexion, extension, lateral bending and rotation loading conditions were simulated, and the ranges of motion were measured and plotted. Results: In flexion, compared to the baseline intact model, the most significant increase in the range of motion was experienced by the isthmic spondylolisthesis model, while in extension, a reduction in the range of motion was measured in both prolonged pars and unilateral pars defect and healthy disc models. In degenerated disc results, the unilateral pars defect and degenerative spondylolisthesis models had the lowest range of motion. No large differences were noticed in lateral bending results. Lastly, in axial rotation, the most significant increase in the range of motion was measured in the isthmic spondylolisthesis model, followed by the spondylolysis model and similarly, in the degenerated disc models. Conclusions: The isthmic spondylolisthesis displayed hypermobility in flexion and rotation. Moreover, the model with unilateral pars defect showed hypermobility in axial rotation only. Finally, hypomobility in all movements was noticed with the degenerative spondylolisthesis model.

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Analiza biomechaniki kręgosłupa w jeździectwie

Szypielewicz S., Andryszczyk M., Siemianowski P., Topoliński T.

Aktualne Problemy Biomechaniki

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2017

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z. 13

57--62

PL

Niniejsza praca przedstawia możliwości analizy motoryki jeźdźca podczas jazdy konnej oraz doskonalenia treningu jeździeckiego poprzez wykorzystanie pomiarów zmian kątów kręgosłupa oraz potencjałów elektrycznych mięśni pleców jeźdźca.

EN

The following research shows the possibilities of motorics analysis of horse-rider in equine sports and improvement of equine training throughout using the progressive measure technologies. Researches includes EMG potential measures of back muscles and measures of angle changes between spine segments.

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A nonlinear analysis of the human vertebral column and medical recommendations that follow

Dietrich M., Kędzior K., Borkowski P., Krzesiński G., Skalski K., Zagrajek T.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2005

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Vol. 53, nr 3

179-194

EN

The analysis of mechanical behaviour of spinal column is until now still a challenge, in spite of the great amount of research which has been conducted over the last years. It is a particularly complex structure considering number of components, their shapes and mechanical characteristics. The objectives of the presented investigations are to understand the mechanisms of the mechanical behaviour of the spine structure and the role of its components, as well as the factors of its dysfunctions as scoliosis discopathy, spondylolisthesis. Also some mechanical effects of surgical interventions by total disc replacement is considered. To account for the 3D character of the spine system including vertebrae, discs, ligaments, muscles etc. the finite element method (FEM) formulation was used throughout the paper. Some specific features of the structure are included in the models as non-conservative loads and muscular tension control performed by the nervous system. The finite element method together with CAD programs and experimental validation was used in investigations of a new type of artificial disc for lumbar spine. The stress analyses were performed for the prostheses being in clinical use and for some original new designs. The conclusions concern most important determinants of the mechanical behaviour of the system and the quality of the intervertebral disc prosthesis.

4

Numerical investigation of a new type of artificial lumbar disc

Borkowski P., Kędzior K., Krzesiński G., Skalski K. R., Wymysłowski P., Zagrajek T.

Journal of Theoretical and Applied Mechanics

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2004

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Vol. 42 nr 2

253-268

EN

The replacement of a damaged lumbar disc by an artificial organ is still not satisfactorily solved problem of surgery. In the study, the finite element method together with CAD programs and experimental validation was used in investigations of a new type of artificial disc for lumbar spine. The present 3D parametrical FE models take into account nonhomogenous properties of tissues, contact with friction between the parts of the analysed systems, large strains and large displacements. The stress analyses were performed for the prostheses being in clinical use and for some new designs. The conclusions concern most important determinants of the mechanical quality of the intervertebral disc prosthesis.

PL

Zastąpienie lędźwiowego krążka miedzykręgowego przez protezę jest wciąż nie w pełni rozwiązanym problemem chirurgii. W pracy zastosowano metodę elementów skończonych, techniki CAD oraz metody weryfikacji eksperymentalnej do poszukiwania konstrukcji nowego typu sztucznego krążka dla odcinka lędźwiowego kręgosłupa. Prezentowane modele metody elementów skończonych uwzględniają niejednorodne właściwości tkanek, występowanie dużych deformacji oraz oddziaływania między poszczególnymi częściami analizowanej struktury. Analizy przeprowadzono dla protez stosowanych obecnie w praktyce klinicznej oraz dla kilku nowych propozycji konstrukcji. Wnioski dotyczą najważniejszych czynników o charakterze mechanicznym, które wpływają na jakość sztucznych krążków międzykręgowych.