Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1997-7-9
pubmed:abstractText
Hip fracture is a common, costly, and debilitating injury occurring primarily in the elderly. Commonly viewed as a consequence of osteoporosis, it is less often appreciated that > 90% of hip fractures are caused by falls, and that fracture risk is governed not only by bone fragility, but also by the mechanics of the fall. Our goal is to develop experimental and mathematical models that describe the dynamics of impact to the hip during a fall, and explain the factors that influence hip contact force and fracture risk during a fall. In the current study, we used "pelvis release experiments" to test the hypothesis that, during a fall on the hip, two pathways exist for energy absorption and force generation at contact: a compressive load path directly in line with the hip, and a flexural load path due to deformation of muscles and ligaments peripheral to the hip. We also explored whether trunk position or muscle contraction influence the body's impact response and the magnitude of force applied to the hip during a fall. Our results suggest that only 15% of total impact force is distributed to structures peripheral to the hip and that peak forces directly applied to the hip are well within the fracture range of the elderly femur. We also found that impacting with the trunk upright significantly increases peak force applied to the hip, whereas muscle contraction has little effect. These results should have application in the development of fracture risk indices that incorporate both fall severity and bone fragility, and the design of interventions such as hip pads and energy-absorbing floors that attempt to reduce fracture risk by decreasing in-line stiffness and hip contact force during a fall.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:issn
0090-6964
pubmed:author
pubmed:issnType
Print
pubmed:volume
25
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
499-508
pubmed:dateRevised
2004-11-17
pubmed:meshHeading
pubmed:articleTitle
Distribution of contact force during impact to the hip.
pubmed:affiliation
Department of Orthopaedic Surgery, Charles A. Dana Research Institute, Harvard-Thorndike Laboratory, Beth Israel Hospital, Boston, MA, USA.
pubmed:publicationType
Journal Article