Exposure to a workday environment results in an increase in anterior tilting of the scapula in dental hygienists with greater employment experience

Clin Biomech (Bristol, Avon). 2012 May;27(4):341-5. doi: 10.1016/j.clinbiomech.2011.10.014. Epub 2011 Nov 9.


Background: Dental hygienists suffer a high incidence of shoulder pathology that seems to increase with job longevity. It has been hypothesized that occupational injuries could be due to local muscle fatigue caused by repetitive low level work and awkward and constrained working postures. In the laboratory, scapular kinematics can be temporarily altered using fatiguing protocols. It is unknown whether or not workday fatigue causes changes to scapular kinematics. The aim of this study was to examine if changes in scapular tilt and rotation occurs after a workday in dental hygienists.

Methods: The pre and post workday scapular kinematics were recorded from dental hygienists using an electromagnetic tracking system. All data were recorded within the place of employment of the dental hygienist.

Results: Following the workday, there was significantly more scapular anterior tilt in dental hygienists (P<0.05); however, no changes were found for upward or internal rotation. Greater kinematic differences were found for hygienists with greater job longevity.

Interpretation: The increase in scapular anterior tilting could be due to post workday fatigue. Anterior tilting of the scapula may have an influence on the development of subacromial impingement syndrome. Hygienists with greater duration of work experience may be at greater risk for developing shoulder injuries as they have more anterior tilting of the scapula post workday.

Publication types

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

MeSH terms

  • Adult
  • Dental Hygienists / statistics & numerical data*
  • Employment / statistics & numerical data*
  • Female
  • Humans
  • Middle Aged
  • Posture / physiology*
  • Scapula / physiology*
  • Workload / statistics & numerical data*
  • Young Adult