Effects of Gender, Preload, and Trunk Angle on Intrinsic Trunk Stiffness

Details

• Personal Author:
  Bazrgari B ; Madigan ML ; Miller EM ; Nussbaum MA
• Description:
  Gender, lifting loads, and flexed trunk postures are three risk factors associated with low back pain. Previous studies have not found gender differences in effective trunk stiffness (intrinsic stiffness plus reflex response) using force perturbations, but these measures may have been confounded by differences in trunk kinematics between males and females. The purpose of this study was to investigate the effects of gender, trunk extensor preload, and trunk flexion angle on intrinsic trunk stiffness using position perturbations, which have the potential to eliminate kinematic differences between research subjects and to separate intrinsic stiffness from reflex responses. A total of 13 males and 12 females were exposed to sudden, small trunk flexion position perturbations with two trunk extension preloads (0 and 30% maximum) and three trunk flexion angles (0, 20, and 40 degrees). Data collected during position perturbations were used along with a two degree of freedom model of the trunk and connecting elements to estimate intrinsic trunk stiffness. Intrinsic stiffness was lower in females compared to males, and increased with increasing preload and trunk flexion angle. Intrinsic stiffness increased more substantially among males with increasing preload and trunk angle, and effects of trunk angle were diminished with a preload. A lower intrinsic stiffness and smaller increases with preload and trunk angle, may contribute to the increased rate of occupational LBP and injury among females. [Description provided by NIOSH]
• Subjects:
  Biomechanical Phenomena Musculoskeletal Diseases Musculoskeletal System Occupational Health Safety Sex Characteristics
• Keywords:
  Author Keywords: Spine Biomechanics Exertion Female Gender Factors Lifting Low Back Low Back Disorders Low Back Pain Male MSD Musculoskeletal Disorders Neuromuscular Control Neuromuscular Function Posture

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• ISSN:
  0218-9577
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Journal Article
• Place as Subject:
  Kentucky ; OSHA Region 3 ; OSHA Region 4 ; Virginia
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Volume:
  15
• Issue:
  2
• NIOSHTIC Number:
  nn:20059648
• Citation:
  J Musculoskelet Res 2012 Jun; 15(2):1250012
• Contact Point Address:
  Michael L. Madigan, Engineering Science and Mechanics, 326 Norris Hall (mail code 0219), Blacksburg, VA 24061
• Email:
  mimadigan@vt.edu
• Federal Fiscal Year:
  2012
• Performing Organization:
  Virginia Polytechnic Institute and State University
• Peer Reviewed:
  False
• Start Date:
  20060801
• Source Full Name:
  Journal of Musculoskeletal Research
• End Date:
  20120731
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:475716a4f019addb0363bbc6bda98f4243f6cc5c53822c9508d6b81a7282557eb96507bbea762c963c9aa45326a0af4ecdd5ac843bdd0f5ee01a6b0188c288cf
• Download URL:
  https://stacks.cdc.gov/view/cdc/223798/cdc_223798_DS1.pdf
• File Type:
  [PDF - 150.41 KB ]