High Magnitude Cyclic Load Triggers Inflammatory Response in Lumbar Ligaments

Details

• Personal Author:
  Davidson B ; King K ; Lu Y ; Solomonow M ; Zhou BH
• Description:
  Background: Cumulative trauma disorder is commonly reported by workers engaged in prolonged repetitive/cyclic occupational activities. Recent experimental evidence confirms that relatively short periods of cyclic lumbar flexion at high loads result in substantial creep of viscoelastic tissues, prolonged periods of its recovery to baseline together with a neuromuscular disorder and exposure to instability. The biochemical process associated with the creep and neuromuscular disorder are not well explored. The purpose of the study is to identify the ligaments as one of the organs of failure and an acute inflammation as the result of failure as a preliminary step in the development of chronic inflammation that might lead to cumulative trauma disorder elicited by high magnitude cyclic loads. Methods: The lumbar spine of anaesthetized cats was subjected to cyclic flexion loading at high magnitudes for six periods of 10 min each with 10 min rest in between followed by 7 h rest. Lumbar displacement was monitored throughout. Supraspinous ligaments from L-3/4, L-4/5, L-5/6 and unloaded T-10/11 were removed at the end of testing and assessed using mRNA expression for cytokine (IL-1β, IL-6, IL-8, TNFa, TGFβ). Cytokines expression in the lumbar ligaments were statistically compared to their self control in the unloaded thoracic ligament. The creep developed during the loading and its recovery during the 7 h rest was calculated. Findings: The mean creep developed during the loading period reached 57.3% recovering to a residual value of 25.5% at the end of the 7 h rest. Increase in cytokine expression was seen in all lumbar ligaments with statistical significance in the L-4/5 and L-5/6 levels. Interpretation: The results confirm that prolonged high magnitude cyclic loading of the lumbar spine in flexion-extension elicits substantial residual creep together with significant increases in cytokines expression, consistent with an acute inflammation, several hours post loading. Further exposure to cyclic loading over time may result in conversion to chronic inflammation. [Description provided by NIOSH]
• Subjects:
  Animals Biomechanical Phenomena Cumulative Trauma Disorders Musculoskeletal Diseases Musculoskeletal System Occupational Health Safety
• Keywords:
  Animal Studies Author Keywords: Spine Back Injuries Biomechanics Chronic Inflammation Cumulative Trauma Disorder Cumulative Trauma Disorders Cyclic Loading Cytokines Inflammation Ligaments Lumbar MSD Musculoskeletal System Disorders Rest Periods

  More +
• ISSN:
  0268-0033
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Journal Article
• Place as Subject:
  Colorado ; Louisiana ; OSHA Region 6 ; OSHA Region 8
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Volume:
  24
• Issue:
  10
• NIOSHTIC Number:
  nn:20068272
• Citation:
  Clin Biomech 2009 Dec; 24(10):792-798
• Contact Point Address:
  Moshe Solomonow, Bioengineering Division and Musculoskeletal Disorders Research Lab., University of Colorado, Denver, Health Sciences Center, 12800 E 19th Ave, RC-1N, Mail Stop 8343, Box 6511, Aurora, CO 80045, USA
• Email:
  moshe.solomonow@ucdenver.edu
• Federal Fiscal Year:
  2010
• Performing Organization:
  Louisiana State University, Health Sciences Center
• Peer Reviewed:
  True
• Start Date:
  20000501
• Source Full Name:
  Clinical Biomechanics
• End Date:
  20031030
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:c1b4cca078cb53252dd279962fc89b793842eb001e83b9c460224f9891c9fb2bedd60ba0e1f5668650b3d1abedbc3c3934ed369c4876146282af9e267f44fdb4
• Download URL:
  https://stacks.cdc.gov/view/cdc/230454/cdc_230454_DS1.pdf
• File Type:
  [PDF - 392.72 KB ]