title: Rate-dependent fracture characteristics of lumbar vertebral bodies.
abstract: Experimental testing incorporating lumbar columns and isolated components is essential to advance the understanding of injury tolerance and for the development of safety enhancements. This study incorporated a whole column axial acceleration model and an isolated vertebral body model to quantify compression rates during realistic loading and compressive tolerance of vertebrae. Eight lumbar columns and 53 vertebral bodies from 23 PMHS were used. Three-factor ANOVA was used to determine significant differences (p<0.05) in physiologic and failure biomechanics based on compression rate, spinal level, and gender. Results demonstrated a significant increase in ultimate force (i.e., fracture) from lower to higher compression rates. Ultimate stress also increased with compression rate. Displacement and strain to failure were consistent at both compression rates. Differences in ultimate mechanics between vertebral bodies obtained from males and females demonstrated non-significant trends, with female vertebral bodies having lower ultimate force that would be associated with decreased injury tolerance. This was likely a result of smaller vertebrae in that population. Combined with existing literature, results presented in this manuscript contribute to the understanding of lumbar spine tolerance during axial loading events that occur in both military and civilian environments with regard to effects of compression rate and gender.
authors.affiliation: Department of Neurosurgery, Medical College of Wisconsin, and Veterans Affairs Medical Center, Milwaukee, WI 53226, United States. Electronic address: bstemper@mcw.edu.
authors.forename: Brian D
authors.initials: BD
authors.lastname: Stemper
authors.affiliation: Department of Neurosurgery, Medical College of Wisconsin, and Veterans Affairs Medical Center, Milwaukee, WI 53226, United States.
authors.forename: Narayan
authors.initials: N
authors.lastname: Yoganandan
authors.affiliation: Department of Neurosurgery, Medical College of Wisconsin, and Veterans Affairs Medical Center, Milwaukee, WI 53226, United States.
authors.forename: Jamie L
authors.initials: JL
authors.lastname: Baisden
authors.affiliation: Department of Neurosurgery, Medical College of Wisconsin, and Veterans Affairs Medical Center, Milwaukee, WI 53226, United States.
authors.forename: Sagar
authors.initials: S
authors.lastname: Umale
authors.affiliation: Department of Neurosurgery, Medical College of Wisconsin, and Veterans Affairs Medical Center, Milwaukee, WI 53226, United States.
authors.forename: Alok S
authors.initials: AS
authors.lastname: Shah
authors.affiliation: Naval Air Warfare Center Aircraft Division, Patuxent River, MD 20670, United States.
authors.forename: Barry S
authors.initials: BS
authors.lastname: Shender
authors.affiliation: Naval Air Warfare Center Aircraft Division, Patuxent River, MD 20670, United States.
authors.forename: Glenn R
authors.initials: GR
authors.lastname: Paskoff
mesh_terms: D005260:Female; D050723:Fractures, Bone / Q000503:physiopathology; D006801:Humans; D007700:Kinetics; D008159:Lumbar Vertebrae / Q000293:injuries* / Q000503:physiopathology; D008297:Male; D008422:Materials Testing; D016474:Weight-Bearing
keywords: Biomechanics; Compression fracture; Gz; Injury tolerance; Lumbar spine; Sex differences