Related Experiment Video
Updated: Sep 28, 2025
08:04
Proximal Cadaveric Femur Preparation for Fracture Strength Testing and Quantitative CT-based Finite Element Analysis
Published on: March 11, 2017
9.5K
Can neck fractures in proximal humeri be predicted by CT-based FEA?
Gal Dahan1, Ori Safran2, Zohar Yosibash1
1School of Mechanical Engineering, The Iby and Aladar Fleischman Faculty of Engineering, Tel-Aviv University, Ramat-Aviv, Israel.
Journal of Biomechanics
|April 5, 2022
Summary
This study improved computational models for predicting proximal humerus fractures in elderly individuals. Enhanced models better predict fracture loads by considering trabecular bone failure, crucial for surgical neck fractures.
Area of Science:
- Biomechanics and Biomaterials
- Orthopedic Surgery
- Computational Modeling
Background:
- Proximal humerus fractures are common in the elderly, particularly at the surgical neck (∼50% incidence).
- Existing in-vitro experiments and CT-based finite element analyses (CTFEA) have limitations in investigating these fractures.
- Previous CTFEA studies primarily focused on anatomical neck fractures, necessitating further research on surgical neck fractures.
Purpose of the Study:
- To enhance CTFEA for improved prediction of humeri mechanical response and yield force in proximal humerus fractures.
- To incorporate surgical neck fractures into experimental and computational investigations.
- To validate CTFEA predictions using digital image correlation (DIC) data from novel experimental setups.
Main Methods:
- Four fresh frozen human humeri were subjected to a new experimental configuration to induce surgical neck fractures.
- Digital image correlation (DIC) was employed to capture surface strains and displacements for CTFEA validation.
- CTFEA were enhanced with a cortical bone mapping (CBM) algorithm and a novel trabecular material mapping approach.
Main Results:
- The experimental setup successfully induced impacted surgical neck fractures in all specimens.
- High correlation was observed between DIC and CTFEA strain predictions at the humerus shaft (R²=0.99) and fair agreement at the neck (R²=0.73).
- Yield load predictions significantly improved when considering trabecular yielding (maximum principal strain criterion) over cortical yielding.
Conclusions:
- CTFEA accurately predicts humerus strains at the shaft and reasonably well at the neck, validating its use with DIC data.
- Trabecular failure laws provide superior yield load prediction for surgical neck fractures compared to cortical failure laws.
- Future FEA studies should utilize trabecular orthotropic constitutive models and failure laws for enhanced fracture prediction.
