The purpose of this study is to characterize the tensile stress of human ribs across the lifespan... more The purpose of this study is to characterize the tensile stress of human ribs across the lifespan. One-hundred six whole ribs from 43 subjects were experimentally tested in a bending scenario using a custom fixture to simulate a dynamic frontal impact. Ages ranged from nine to 92 years old, with a mean age of 60 years and representation in each decade. Strain gauges on each rib were used to determine time of failure. Post-impact, a section adjacent to the fracture site was used for precise calculations of geometric properties. Tensile stress due to bending was determined at the time of fracture for each rib, and results indicate a significant decline in stress with increasing age. This research may be particularly useful for application in the construction of finite element models. Rib material properties in the context of structural response as presented here can aid with advancing knowledge about age-related changes in the rib as well as having implications for better understanding of whole thorax response and injury.
Journal of the Mechanical Behavior of Biomedical Materials, Jan 2015
Traumatic injury from motor vehicle crashes is a major cause of morbidity and mortality in the Un... more Traumatic injury from motor vehicle crashes is a major cause of morbidity and mortality in the United States. The thorax is particularly at risk in motor vehicle crashes and is studied extensively by the injury biomechanics community. Unfortunately, most samples used in such research generally do not include children or the very elderly, despite the common occurrence of thorax injuries at both ends of the age spectrum. Rib fractures in particular, are one of the most common injuries, especially in the elderly, and can greatly affect morbidity, mortality, and quality of life. As the proportion of older adults in the population increases, such age-related fragility fractures will continually grow as a worldwide problem. Additionally, the risk of rib fracture significantly increases with age with confounding deleterious effects. Studies on elderly ribs are not uncommon, however very few studies exist which explore the mechanical properties and behavior of immature human bone, especially of ribs. Previous research identifying rib properties has provided useful information for numerous applications. However, no study has included a comprehensive sample of all ages (pediatric through elderly) in which ribs are tested in the same repeatable set-up. The goal of this study is to characterize differences in rib structural response across the age spectrum. One-hundred forty excised ribs from 70 individuals were experimentally tested in a custom-built pendulum fixture simulating a dynamic frontal impact. The sample includes individuals of ages ranging from six to 99 years old and includes 58 males and 12 females. Reported data include fracture location, displacement in the X and Y directions at fracture (δX, δY), force at fracture (FX), and linear structural stiffness (K). δX and K exhibit a statistically significant linear decrease with age (p<0.0001). FX reveals a trend in which a peak is reached in the young adult years (25-40). Detailed mechanical property data, as provided here, will prove useful for application in computational modeling efforts, which are vital to help prevent injury and to understand injury mechanisms from childhood through old age.
The purpose of this study is to characterize the tensile stress of human ribs across the lifespan... more The purpose of this study is to characterize the tensile stress of human ribs across the lifespan. One-hundred six whole ribs from 43 subjects were experimentally tested in a bending scenario using a custom fixture to simulate a dynamic frontal impact. Ages ranged from nine to 92 years old, with a mean age of 60 years and representation in each decade. Strain gauges on each rib were used to determine time of failure. Post-impact, a section adjacent to the fracture site was used for precise calculations of geometric properties. Tensile stress due to bending was determined at the time of fracture for each rib, and results indicate a significant decline in stress with increasing age. This research may be particularly useful for application in the construction of finite element models. Rib material properties in the context of structural response as presented here can aid with advancing knowledge about age-related changes in the rib as well as having implications for better understanding of whole thorax response and injury.
Journal of the Mechanical Behavior of Biomedical Materials, Jan 2015
Traumatic injury from motor vehicle crashes is a major cause of morbidity and mortality in the Un... more Traumatic injury from motor vehicle crashes is a major cause of morbidity and mortality in the United States. The thorax is particularly at risk in motor vehicle crashes and is studied extensively by the injury biomechanics community. Unfortunately, most samples used in such research generally do not include children or the very elderly, despite the common occurrence of thorax injuries at both ends of the age spectrum. Rib fractures in particular, are one of the most common injuries, especially in the elderly, and can greatly affect morbidity, mortality, and quality of life. As the proportion of older adults in the population increases, such age-related fragility fractures will continually grow as a worldwide problem. Additionally, the risk of rib fracture significantly increases with age with confounding deleterious effects. Studies on elderly ribs are not uncommon, however very few studies exist which explore the mechanical properties and behavior of immature human bone, especially of ribs. Previous research identifying rib properties has provided useful information for numerous applications. However, no study has included a comprehensive sample of all ages (pediatric through elderly) in which ribs are tested in the same repeatable set-up. The goal of this study is to characterize differences in rib structural response across the age spectrum. One-hundred forty excised ribs from 70 individuals were experimentally tested in a custom-built pendulum fixture simulating a dynamic frontal impact. The sample includes individuals of ages ranging from six to 99 years old and includes 58 males and 12 females. Reported data include fracture location, displacement in the X and Y directions at fracture (δX, δY), force at fracture (FX), and linear structural stiffness (K). δX and K exhibit a statistically significant linear decrease with age (p<0.0001). FX reveals a trend in which a peak is reached in the young adult years (25-40). Detailed mechanical property data, as provided here, will prove useful for application in computational modeling efforts, which are vital to help prevent injury and to understand injury mechanisms from childhood through old age.
Uploads
Papers by Susan White