Analýza 6 velkých PMMA lebečních implantátů pomocí metody konečných prvků: multikriteriální hodnotící přístup

Finite element analysis of 6 large PMMA skull reconstructions: A multi-criteria evaluation approach

journal article in Web of Science

en

In this study 6 pre-operative designs for PMMA based reconstructions of cranial defects were evaluated for their mechanical robustness using finite element modeling. Clinical experience and engineering principles were employed to create multiple plan options, which were subsequently computationally analyzed for mechanically relevant parameters under 50N loads: stress, strain and deformation in various components of the assembly. The factors assessed were: defect size, location and shape. The major variable in the cranioplasty assembly design was the arrangement of the fixation plates. An additional study variable introduced was the location of the 50N load within the implant area. It was found that in smaller defects, it was simpler to design a symmetric distribution of plates and under limited variability in load location it was possible to design an optimal for expected loads. However, for very large defects with complex shapes, the variability in the load locations introduces complications to the intuitive design of the optimal assembly. The study shows that it can be beneficial to incorporate multi design computational analyses to decide upon the most optimal plan for a clinical case.

V této studii bylo provedeno 6 předoperačních návrhů pro rekonstrukci kraniálních defektů pomocí PMMA implantátů, které byly hodnoceny z mechanického hlediska pomocí výpočtového modelování metodou konečných prvků. Pomocí inženýrského přístupu a klinických zkušeností byly vytvořeny různé varianty výpočtových modelů. Veličinami, které byly následně výpočetně analyzovány při zatížení 50N jsou napětí, deformace a deformace. Hodnotící faktory byly: velikost defektu, umístění a tvar. Posouzení sestavy s kranioplastikou bylo provedeno pro různé uspořádání fixačních desek. Dále byla analyzována poloha zatížení 50N v oblasti implantátu.

In this study 6 pre-operative designs for PMMA based reconstructions of cranial defects were evaluated for their mechanical robustness using finite element modeling. Clinical experience and engineering principles were employed to create multiple plan options, which were subsequently computationally analyzed for mechanically relevant parameters under 50N loads: stress, strain and deformation in various components of the assembly. The factors assessed were: defect size, location and shape. The major variable in the cranioplasty assembly design was the arrangement of the fixation plates. An additional study variable introduced was the location of the 50N load within the implant area. It was found that in smaller defects, it was simpler to design a symmetric distribution of plates and under limited variability in load location it was possible to design an optimal for expected loads. However, for very large defects with complex shapes, the variability in the load locations introduces complications to the intuitive design of the optimal assembly. The study shows that it can be beneficial to incorporate multi design computational analyses to decide upon the most optimal plan for a clinical case.

Kranioplastika; MKP; PMMA; Kraniální implantát; Mechanické vlastnosti; Rozložení fixátorů

Cranioplasty; FEM; PMMA; Cranial implant; Mechanical properties; plate distribution; fixation geometry

13.06.2017

PLOS

1932-6203

12

6

1–16

16