Femoral strength and strains in sideways fall : Validation of finite element models against bilateral strain measurements
Kok, Joeri LU
; Grassi, Lorenzo
LU
; Gustafsson, Anna
LU
and Isaksson, Hanna
LU
(2021)
In Journal of Biomechanics
122.
- Abstract
Low impact falls to the side are the main cause of hip fractures in elderly. Finite element (FE) models of the proximal femur may help in the assessment of patients at high risk for a hip fracture. However, extensive validation is essential before these models can be used in a clinical setting. This study aims to use strain measurements from bilateral digital image correlation to validate an FE model against ex vivo experimental data of proximal femora under a sideways fall loading condition. For twelve subjects, full-field strain measurements were available on the medial and lateral side of the femoral neck. In this study, subject-specific FE models were generated based on a consolidated procedure previously validated for stance... (More)
Low impact falls to the side are the main cause of hip fractures in elderly. Finite element (FE) models of the proximal femur may help in the assessment of patients at high risk for a hip fracture. However, extensive validation is essential before these models can be used in a clinical setting. This study aims to use strain measurements from bilateral digital image correlation to validate an FE model against ex vivo experimental data of proximal femora under a sideways fall loading condition. For twelve subjects, full-field strain measurements were available on the medial and lateral side of the femoral neck. In this study, subject-specific FE models were generated based on a consolidated procedure previously validated for stance loading. The material description included strain rate dependency and separate yield and fracture strain limits in tension and compression. FE predicted fracture force and experimentally measured peak forces showed a strong correlation (R2 = 0.92). The FE simulations predicted the fracture initiation within 3 mm distance of the experimental fracture line for 8/12 subjects. The predicted and measured strains correlated well on both the medial side (R2 = 0.87) and the lateral side (R2 = 0.74). The lower correlation on the lateral side is attributed to the irregularity of the cortex and presence of vessel holes in this region. The combined validation against bilateral full-field strain measurements and peak forces has opened the door for a more elaborate qualitative and quantitative validation of FE models of femora under sideways fall loading.
(Less)
- author
- Kok, Joeri
LU
; Grassi, Lorenzo
LU
; Gustafsson, Anna
LU
and Isaksson, Hanna
LU
- organization
- publishing date
- 2021
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Finite Element Modeling, Digital Image Correlation, Bone strength, sideways fall, Hip fracture
- in
- Journal of Biomechanics
- volume
- 122
- article number
- 110445
- publisher
- Elsevier
- external identifiers
-
- scopus:85104907897
- pmid:33933857
- ISSN
- 1873-2380
- DOI
- 10.1016/j.jbiomech.2021.110445
- language
- English
- LU publication?
- yes
- id
- 5efbac98-3cbc-4787-a3f6-a4b0af0c378a
- date added to LUP
- 2021-05-06 07:13:55
- date last changed
- 2024-04-20 05:51:51
@article{5efbac98-3cbc-4787-a3f6-a4b0af0c378a,
abstract = {{<p>Low impact falls to the side are the main cause of hip fractures in elderly. Finite element (FE) models of the proximal femur may help in the assessment of patients at high risk for a hip fracture. However, extensive validation is essential before these models can be used in a clinical setting. This study aims to use strain measurements from bilateral digital image correlation to validate an FE model against ex vivo experimental data of proximal femora under a sideways fall loading condition. For twelve subjects, full-field strain measurements were available on the medial and lateral side of the femoral neck. In this study, subject-specific FE models were generated based on a consolidated procedure previously validated for stance loading. The material description included strain rate dependency and separate yield and fracture strain limits in tension and compression. FE predicted fracture force and experimentally measured peak forces showed a strong correlation (R2 = 0.92). The FE simulations predicted the fracture initiation within 3 mm distance of the experimental fracture line for 8/12 subjects. The predicted and measured strains correlated well on both the medial side (R2 = 0.87) and the lateral side (R2 = 0.74). The lower correlation on the lateral side is attributed to the irregularity of the cortex and presence of vessel holes in this region. The combined validation against bilateral full-field strain measurements and peak forces has opened the door for a more elaborate qualitative and quantitative validation of FE models of femora under sideways fall loading.</p>}},
author = {{Kok, Joeri and Grassi, Lorenzo and Gustafsson, Anna and Isaksson, Hanna}},
issn = {{1873-2380}},
keywords = {{Finite Element Modeling; Digital Image Correlation; Bone strength; sideways fall; Hip fracture}},
language = {{eng}},
publisher = {{Elsevier}},
series = {{Journal of Biomechanics}},
title = {{Femoral strength and strains in sideways fall : Validation of finite element models against bilateral strain measurements}},
url = {{http://dx.doi.org/10.1016/j.jbiomech.2021.110445}},
doi = {{10.1016/j.jbiomech.2021.110445}},
volume = {{122}},
year = {{2021}},
}