Strain distribution in the proximal human femur during in vitro simulated sideways fall
Zani, Lorenzo ; Erani, Paolo ; Grassi, Lorenzo LU
; Taddei, Fulvia
and Cristofolini, Luca
(2015)
In Journal of Biomechanics
48(10).
p.2130-2143
- Abstract
- This study assessed: (i) how the magnitude and direction of principal strains vary for different sideways fall loading directions; (ii) how the principal strains for a sideways fall differ from physiological loading directions; (iii) the fracture mechanism during a sideways fall. Eleven human femurs were instrumented with 16 triaxial strain gauges each. The femurs were non-destructively subjected to: (a) six loading configurations covering the range of physiological loading directions; (b) twelve configurations simulating sideways falls. The femurs were eventually fractured in a sideways fall configuration while high-speed cameras recorded the event. When the same force magnitude was applied, strains were significantly larger in a sideways... (More)
- This study assessed: (i) how the magnitude and direction of principal strains vary for different sideways fall loading directions; (ii) how the principal strains for a sideways fall differ from physiological loading directions; (iii) the fracture mechanism during a sideways fall. Eleven human femurs were instrumented with 16 triaxial strain gauges each. The femurs were non-destructively subjected to: (a) six loading configurations covering the range of physiological loading directions; (b) twelve configurations simulating sideways falls. The femurs were eventually fractured in a sideways fall configuration while high-speed cameras recorded the event. When the same force magnitude was applied, strains were significantly larger in a sideways fall than for physiological loading directions (principal compressive strain was 70% larger in a sideways fall). Also the compressive-to-tensile strain ratio was different: for physiological loading the largest compressive strain was only 30% larger than the largest tensile strain; but for the sideways fall, compressive strains were twice as large as the tensile strains. Principal strains during a sideways fall were nearly perpendicular to the direction of principal strains for physiological loading. In the most critical regions (medial part of the head-neck) the direction of principal strain varied by less than 9° between the different physiological loading conditions, whereas it varied by up to 17° between the sideways fall loading conditions. This was associated with a specific fracture mechanism during sideways fall, where failure initiated on the superior-lateral side (compression) followed by later failure of the medially (tension), often exhibiting a two-peak force-displacement curve. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/5159551
- author
- Zani, Lorenzo
; Erani, Paolo
; Grassi, Lorenzo
LU
; Taddei, Fulvia
and Cristofolini, Luca
- publishing date
- 2015
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Hip fractures, Sideways fall, Physiological loading, Strain distribution, Direction of principal strain, Structural optimization
- in
- Journal of Biomechanics
- volume
- 48
- issue
- 10
- pages
- 2130 - 2143
- publisher
- Elsevier
- external identifiers
-
- scopus:84937524579
- pmid:25843261
- ISSN
- 1873-2380
- DOI
- 10.1016/j.jbiomech.2015.02.022
- language
- English
- LU publication?
- no
- id
- 72eb59aa-8048-4638-b515-876f7c75651b (old id 5159551)
- date added to LUP
- 2016-04-01 10:42:33
- date last changed
- 2022-03-27 18:46:19
@article{72eb59aa-8048-4638-b515-876f7c75651b,
abstract = {{This study assessed: (i) how the magnitude and direction of principal strains vary for different sideways fall loading directions; (ii) how the principal strains for a sideways fall differ from physiological loading directions; (iii) the fracture mechanism during a sideways fall. Eleven human femurs were instrumented with 16 triaxial strain gauges each. The femurs were non-destructively subjected to: (a) six loading configurations covering the range of physiological loading directions; (b) twelve configurations simulating sideways falls. The femurs were eventually fractured in a sideways fall configuration while high-speed cameras recorded the event. When the same force magnitude was applied, strains were significantly larger in a sideways fall than for physiological loading directions (principal compressive strain was 70% larger in a sideways fall). Also the compressive-to-tensile strain ratio was different: for physiological loading the largest compressive strain was only 30% larger than the largest tensile strain; but for the sideways fall, compressive strains were twice as large as the tensile strains. Principal strains during a sideways fall were nearly perpendicular to the direction of principal strains for physiological loading. In the most critical regions (medial part of the head-neck) the direction of principal strain varied by less than 9° between the different physiological loading conditions, whereas it varied by up to 17° between the sideways fall loading conditions. This was associated with a specific fracture mechanism during sideways fall, where failure initiated on the superior-lateral side (compression) followed by later failure of the medially (tension), often exhibiting a two-peak force-displacement curve.}},
author = {{Zani, Lorenzo and Erani, Paolo and Grassi, Lorenzo and Taddei, Fulvia and Cristofolini, Luca}},
issn = {{1873-2380}},
keywords = {{Hip fractures; Sideways fall; Physiological loading; Strain distribution; Direction of principal strain; Structural optimization}},
language = {{eng}},
number = {{10}},
pages = {{2130--2143}},
publisher = {{Elsevier}},
series = {{Journal of Biomechanics}},
title = {{Strain distribution in the proximal human femur during in vitro simulated sideways fall}},
url = {{http://dx.doi.org/10.1016/j.jbiomech.2015.02.022}},
doi = {{10.1016/j.jbiomech.2015.02.022}},
volume = {{48}},
year = {{2015}},
}