Strength and Stability of a Motorized Unilateral External Fixation Device for Fractures and Bone Loss under Compressive Load

Subject Areas :

Alireza Bahramkia ^{1 *} , Mehran Fakhraie ² , Salar Khajehpour ³ , Seyed Mohammad Tahami ⁴ , Raheb Gholami ⁵

1 - Department of Mechanical Engineering, Sarvestan Branch, Islamic Azad University, Sarvestan, Iran
2 - Department of Mechanical Engineering, Lahijan Branch, Islamic Azad University, Lahijan, Iran
3 - Department of Mechanical Engineering, Lahijan Branch, Islamic Azad University, Lahijan, Iran
4 - Department of Mechanical Engineering, Lahijan Branch, Islamic Azad University, Lahijan, Iran
5 - Department of Mechanical Engineering, Lahijan Branch, Islamic Azad University, Lahijan, Iran

Received: 2025-01-02 Accepted : 2025-02-14 Published : 2025-02-27

Keywords: Unilateral External Bone Fixator, Bone Fracture, Bone Loss, Orthopedics, FEM,

Abstract :

Aligning broken bones using a unilateral external bone fixator has become popular today. One of the advantages of unilateral external bone fixators is their ease of installation and adjustment compared to circular and horseshoe models. Unlike circular and horseshoe-shaped models, the advantages of unilateral external bone fixators are ease of installation and adjustability. The present research aims to ensure the stability and strength of the unilateral motorized external bone fixation device, equipped with four motors designed and then built in SolidWorks software under a compressive load of 150N when the motors are in motion. The device was simulated and analyzed using the Finite Element Method (FEM) in ANSYS software. Then, the constructed device was tested in the laboratory by applying a compressive force of 150N. The results of the simulation and experimental method of compressive force application and examination of the reliability coefficient using the FEM in the simulated method indicated that: The device is designed with the necessary stability, rigidity, and reliability to stabilize fractured long bones with the ability to move broken long bones where part of the bone has been lost. The device has precise bone movement and four independent motorized units; based on the patient's needs and the specialist's instructions, bone formation is possible.

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