A novel sideways fall simulator to study hip fractures ex vivo

• Published in: PloS one Vol. 13; no. 7; p. e0201096
• Main Authors: Fleps, Ingmar, Vuille, Muriel, Melnyk, Angela, Ferguson, Stephen J., Guy, Pierre, Helgason, Benedikt, Cripton, Peter A.
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 24.07.2018; Public Library of Science (PLoS)
• Subjects: Bioaccumulation; Biology and Life Sciences; Biomechanics; Biomedical engineering; Boundary conditions; Cadavers; Cameras; CAT scans; Contact force; Deformation; Deformation mechanisms; Diagnosis; Engineering and Technology; Experiments; Femur; Finite element method; Fractures; Geriatrics; High speed cameras; Hip; Hip fractures; Hip joint; Injuries; Load; Mechanical engineering; Medicine and Health Sciences; Older people; Pelvis; Physical Sciences; Posture; Risk factors; Studies; Trauma; Trochanter; Ultrasonic testing; Canada; Switzerland
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0201096

Falls to the side are the leading cause of hip fractures in the elderly. The load that a person experiences during a fall cannot be measured with volunteers for ethical reasons. To evaluate injurious loads, while considering relevant energy input and body posture for a sideways fall, a subject-specific cadaveric impact experiment was developed. Full cadaveric femur-pelvis constructs (N = 2) were embedded in surrogate soft tissue material and attached to metallic surrogate lower limbs. The specimens were then subjected to an inverted pendulum motion, simulating a fall to the side with an impact to the greater trochanter. The load at the ground and the deformation of the pelvis were evaluated using a 6-axis force transducer and two high-speed cameras. Post-test, a trauma surgeon (PG) evaluated specimen injuries. Peak ground contact forces were 7132 N and 5641 N for the fractured and non-fractured specimen, respectively. We observed a cervical fracture of the femur in one specimen and no injuries in a second specimen, showing that the developed protocol can be used to differentiate between specimens at high and low fracture risk.