In Vivo Load-Relaxation of the Trunk with Prolonged Flexion

Details

• Personal Author:
  Bazrgari B ; Hendershot B ; Muslim K ; Nussbaum MA ; Toosizadeh N
• Description:
  Many occupational tasks require prolonged trunk flexion, and such exposures are associated with an increased risk of low back disorders (LBDs). Understanding the mechanical and physiological consequences of flexion is complicated by time-dependent responses to sustained trunk postures. As such, an accurate assessment of load partitioning among passive and active components of the human trunk, such as in biomechanical models, requires a realistic representation of rate-dependent passive properties. While creep and load-relaxation responses of the spine under axial loading have been extensively investigated, viscoelastic responses to prolonged trunk flexion, in particular load-relaxation behaviors, have not been sufficiently described. Hence, the main purpose of this study was to quantify the load-relaxation response of the human trunk during prolonged flexed postures. Load-relaxation responses of the trunk were measured in vivo at different trunk flexion angles and exposure durations. Measured trunk responses were then fit using a viscoelastic model. We hypothesized that the trunk would exhibit nonlinear viscoelastic responses to prolonged flexion and that these would depend on the trunk flexion angle. [Description provided by NIOSH]
• Subjects:
  Biomechanical Phenomena Musculoskeletal Diseases Musculoskeletal System Occupational Health Safety
• Keywords:
  Biomechanical Modeling Biomechanics Low Back Disorders Low Back Pain MSD Musculoskeletal Disorders Posture
• Publisher:
  American Society of Biomechanics
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Abstract or Summary
• Place as Subject:
  OSHA Region 3 ; Virginia
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  51
• NIOSHTIC Number:
  nn:20059655
• Citation:
  Proceedings of the 34th Annual Meeting of the American Society of Biomechanics, August 18-21, 2010, Providence, Rhode Island. Newark, DE: The American Society of Biomechanics, 2010 Aug; :51
• Contact Point Address:
  Maury A. Nussbaum, Industrial & Systems Engineering, Virginia Tech, Blacksburg, VA, USA
• Email:
  nussbaum@vt.edu
• Federal Fiscal Year:
  2010
• Performing Organization:
  Virginia Polytechnic Institute and State University
• Peer Reviewed:
  False
• Start Date:
  20060801
• Source Full Name:
  Proceedings of the 34th Annual Meeting of the American Society of Biomechanics, August 18-21, 2010, Providence, Rhode Island
• End Date:
  20120731
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:25b5070faf4ff2c5c3edbc9b28d80ee856383407bc6df3b26ee7f5f0b726f1e2c00e97fef0491f790f2cd4d5a58e71ade848ce6690606db2096b8b427833bf7d
• Download URL:
  https://stacks.cdc.gov/view/cdc/223804/cdc_223804_DS1.pdf
• File Type:
  [PDF - 263.91 KB ]