# Finite Element Analysis of Von Mises Stress in External Fixators for Open Tibial Fractures: A Comparative Study of ASTM F1541‐02 and Tibia‐Based Models in Indonesian Patients

## TL;DR

This study compares standard and patient-specific models of external fixators for tibial fractures in Indonesian patients using finite element analysis.

## Contribution

The study introduces a finite element analysis of external fixators tailored to Indonesian patients using both standard and patient-specific models.

## Key findings

- Stresses predicted by ASTM F1541-02 were higher than those from the tibia-based model under torsion and bending.
- All stress values remained below material yield strength, indicating the fixator design is safe.
- Tibia-based modeling provides more physiologically realistic predictions than standard protocols.

## Abstract

Traffic accidents are the leading cause of traumatic fractures worldwide, with tibial fractures being the most common lower‐extremity injury. Open tibial fractures pose significant clinical challenges due to their high risk of infection and non‐union, requiring effective stabilisation. External fixators are widely used for this purpose, but their biomechanical performance must be evaluated under both standardised and patient‐specific conditions. This study presents a finite element analysis of an external fixator tailored to Indonesian patients, using two frameworks: the ASTM F1541‐02 standard protocol and a tibia‐based model derived from patient geometry. Von Mises stress distributions were assessed under axial compression, torsional loading, and four‐point bending. Results showed that stresses predicted by ASTM F1541‐02 were consistently higher than those from the tibia‐based model, particularly under torsion and bending, though all values remained below material yield strength. These findings indicate that the fixator design is safe, while emphasising that tibia‐based modelling provides more physiologically realistic predictions. The study shows the importance of patient‐specific anatomy in computational biomechanics and points to future directions in design optimisation and localized manufacturing.

Traffic accidents are the most common cause of fractures, where tibia fractures become the most common case of lower extremity fractures. External fixators have been widely used for the treatment of open tibial fractures. The present study contributes to providing an overview of the phenomenon of external fixator installation in open tibia fracture cases for Indonesian patients.