Analysis of near cortex versus both cortex screw fixation in bone fracture surgery

Abstract

Fractures are commonly encountered injuries due to falls and accidents in humans. A method of stabilizing a fracture is the usage of Locking Compression Plates (LCPs). Accelerated healing is achieved through critical compressive stresses exerted by the bone-plate secured with screws. Prompt healing can occur when the blood supply to bone is maintained or restored early.

This project seeks to create and validate fracture fixation models of 8-hole and 9-hole LCPs together with Locking Head Screws (LHS) on long bones through Finite Element Method (FEM). The validation processes were done with Finite Element (FE) simulation of 3-point bending conditions on the LCPs, axial loading and 4-point bending conditions on the plate-bone constructs. The FE simulation results were then validated by experimental data. The validated models will pave the way in determining the type and size of over-drilled holes at the near cortex that will reduce stiffness and eventually allow for optimized bone healing.

In the initial validation process, the models of 8-hole and 9-hole LCPs have stiffness values within 5 % deviation of the actual bone-plates. The validated LCP models are then assembled as plate-bone constructs with LHS and synthetic bone models for further validation.