Bending Analysis of Clavicle Using LS-DYNA

Overview

Various surgical procedures are used to treat distal clavicle fractures. However, rigid internal fixation for reduction and secure hold is difficult because the distal fragment is small and the fracture site is near the acromioclavicular joint. In this study, in order to elucidate on the method suitable for the fixation of distal clavicle fractures, we compared three internal fixation methods using stiffness as the indicator. After a finite element (FE) simulation showed a significant difference for the two plate methods, we next investigated which of these was the more useful for clinical application.

Characteristics:

  • Based on the micro CT data which separated into three
  • Segmentation tools to aid separation of bone and plate
  • Integration of the three models using CAD module
  • FE analysis using LS-DYNA
  • Comparison of the results of analysis of two plates

Thanks to

Rica SakaiKitasato University

JSOL

Image Processing

The CT slices images data were imported into ScanIP, and using grey level based segmentation tools, created each the three masks representing the implant and clavicle, scapula. Then the model exported to +CAD Module, and merging to one part using CAD Manipulation tool in the +CAD Module. These models were then voxelised, and exported back into ScanIP.

Mesh Generation

Created High quality and smooth mesh was using the +FE Free algorithm. Some parameters were manually adjusted to tune the mesh further. These model's meshes were about 270000 elements, and the meshing time was about 20 minutes.

Simulation

The generated mesh was exported in LS- DYNA format and read directly into LS- DYNA analysis for simulation. Performed an FE simulation on these two types of plate, and found that the relative displacement of the non-locking plate with arm was smaller than that of the locking plate with hook. Stress analysis of the locking plate with hook revealed that high stress was exerted on the contact site between hook and bone.