Effect of higher frequency components and duration of vibration on bone tissue alterations in the rat-tail model

Ind Health. 2015;53(3):245-59. doi: 10.2486/indhealth.2014-0117. Epub 2015 Apr 4.

Abstract

To formulate more accurate guidelines for musculoskeletal disorders (MSD) linked to Hand-Arm Vibration Syndrome (HAVS), delineation of the response of bone tissue under different frequencies and duration of vibration needs elucidation. Rat-tails were vibrated at 125 Hz (9 rats) and 250 Hz (9 rats), at 49 m/s(2), for 1D (6 rats), 5D (6 rats) and 20D (6 rats); D=days (4 h/d). Rats in the control group (6 rats for the vibration groups; 2 each for 1D, 5D, and 20D) were left in their cages, without being subjected to any vibration. Structural and biochemical damages were quantified using empty lacunae count and nitrotyrosine signal-intensity, respectively. One-way repeated-measure mixed-model ANOVA at p<0.05 level of significance was used for analysis. In the cortical bone, structural damage quantified through empty lacunae count was significant (p<0.05) at 250 Hz (10.82 ± 0.66) in comparison to the control group (7.41 ± 0.76). The biochemical damage was significant (p<0.05) at both the 125 Hz and 250 Hz vibration frequencies. The structural damage was significant (p<0.05) at 5D for cortical bone while the trabecular bone showed significant (p<0.05) damage at 20D time point. Further, the biochemical damage increased with increase in the duration of vibration with a significant (p<0.05) damage observed at 20D time point and a near significant change (p=0.08) observed at 5D time point. Structural and biochemical changes in bone tissue are dependent upon higher vibration frequencies of 125 Hz, 250 Hz and the duration of vibration (5D, 20D).

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Bone and Bones / chemistry*
  • Bone and Bones / pathology*
  • Male
  • Rats
  • Rats, Sprague-Dawley
  • Time Factors
  • Tyrosine / analogs & derivatives*
  • Tyrosine / analysis
  • Vibration / adverse effects*

Substances

  • 3-nitrotyrosine
  • Tyrosine