Aging, Neuromuscular Behavior, and Risk of Occupational Low Back Pain

Details

• Personal Author:
  Bazrgari B ; Elder W ; Kryscio R ; Nussbaum M ; Reed D
• Description:
  Low back disorders, and low back pain (LBP) in particular, continue to be the leading cause of worker disability in the United States, accounting for approximately 40% of all reported occupational musculoskeletal disorders annually. Reducing the incidence and severity of LBP is also a strategic goal within most sectors in the recent NIOSH National Occupational Research Agenda. Epidemiological studies have identified a number of physical, psychosocial, and personal factors that increase the risk of developing LBP. Among the latter, age is of particular significance given the increasing numbers and proportions of older workers and the higher prevalence of LBP among them. Understanding the underlying mechanisms, specifically identifying the links between aging and a higher incidence of LBP, is an essential prerequisite for developing better control and management of such disorders in the aging workforce. Over the project period, we investigated the role of several biomechanical mechanisms potentially linking natural aging with a higher incidence of LBP. We were interested in knowing whether age-related changes in lower back tissues would adversely affects lower back biomechanics, specifically the forces and deformations experienced within the lower back under various occupational activities. To achieve our objective, we completed two specific aims: 1) quantify alterations in trunk mechanical behavior with age, and 2) quantify the association between alterations in trunk mechanical behavior and spine biomechanics. These aims were completed by studying low back biomechanics among 60 workers (30 males and 30 females), including 12 workers in each of the following age groups: 20s, 30s, 40s, 50s, and 60s. Workers were recruited to minimize the effects of factors other than natural aging on our measures of lower back biomechanics. Trunk resistance to passive deformation and the subsequent viscoelastic relaxation were found to increase with aging while trunk intrinsic stiffness did not change. On a more functional level, the contribution of the lumbar spine to total trunk forward bending under simple flexion-extension activity as well as during symmetric manual material handing tasks was found to decrease with aging. Such functional changes with aging are likely due to underlying age-related changes in trunk mechanical behaviors and were found to adversely affect the mechanical loading on the lower back. Specifically, age-related alterations in the manner in which workers performed symmetric manual material handling were found to be associated with higher shearing forces on the worker's lower back. Investigating the role of biomechanical factors in the occurrence of occupational low back pain is a complex activity because of the influence of many occupational and non-occupational factors on lower back biomechanics. Given the cumulative nature of many work-related musculoskeletal disorders, including low back pain, results of this project have established a baseline for our future research wherein the influence of long-term exposure to important occupational factors (e.g., repetitive task) can be effectively distinguished from the effects of natural aging. [Description provided by NIOSH]
• Subjects:
  Coal Coal Mining Electromagnetic Phenomena Mining Occupational Health Radio Waves Safety
• Keywords:
  Age Factors Aging Back Injuries Biomechanics Low Back Disorders Low Back Pain Manual Materials Handling MSD Muscle Function Musculoskeletal Disorders Repetitive Work

  More +
• Series:
  Grant Final Reports
• Publisher:
  National Institute for Occupational Safety and Health
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Final Grant Report
• Place as Subject:
  Kentucky ; OSHA Region 3 ; OSHA Region 4 ; Virginia
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  OEP - Office of Extramural Programs
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  1-57
• NIOSHTIC Number:
  nn:20053547
• NTIS Accession Number:
  PB2019-100316
• Citation:
  Atlanta, GA: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, R21-OH-010195, 2015 Sep; :1-57
• Contact Point Address:
  Babak Bazrgari, 514E Robotic and Manufacturing Building, 143 Graham Ave., Lexington KY, 40506-0108
• Email:
  babak.bazrgari@uky.edu
• Federal Fiscal Year:
  2015
• Performing Organization:
  University of Kentucky
• Peer Reviewed:
  False
• Start Date:
  20120701
• Source Full Name:
  National Institute for Occupational Safety and Health
• End Date:
  20150630
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:c921ba132399c5d4921b1d30718ffe64b58d212bd0ec11acfe28df164ecd9c4bc39461c4e29ba9947a027b233070ba5165f27b963deb2671db4660e7c99be01e
• Download URL:
  https://stacks.cdc.gov/view/cdc/218769/cdc_218769_DS1.pdf
• File Type:
  [PDF - 1.79 MB ]