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Author Spotlight: Enhancing Small Animal Bone Compression Testing for Research
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Cervical spine joint loading with neck flexion.

Jeff Matthew Barrett1, Colin McKinnon1, Jack P Callaghan1

  • 1Department of Kinesiology, University of Waterloo, Waterloo, Canada.

Ergonomics
|October 10, 2019
PubMed
Summary
This summary is machine-generated.

Smartphone use causes

Keywords:
Flexioncompressionnecksheartext neck

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Area of Science:

  • Biomechanics
  • Spine Research
  • Ergonomics

Background:

  • Cervical spine flexion, common with digital device use ('text neck'), is a risk factor for chronic neck pain.
  • Limited research quantifies cervical spine joint loads during flexion, considering muscle activation.

Purpose of the Study:

  • To quantify compression and anteroposterior (AP) shear forces in the cervical spine during 45-degree flexion compared to a neutral posture.
  • To investigate the mechanical basis for neck pain associated with prolonged flexion postures.

Main Methods:

  • Eight healthy males performed 45-degree cervical spine flexion tasks.
  • 3D head-trunk angles and surface electromyography of 10 neck muscles were recorded.
  • An inverse dynamics model computed intervertebral joint forces (compression and AP shear).

Main Results:

  • Cervical spine flexion increased compression twofold and anterior shear fourfold in the upper spine compared to neutral posture.
  • Compression increased from cranial to caudal, leveling off at C5-C6.
  • Anterior shear dramatically decreased in the lower cervical spine during flexion.

Conclusions:

  • Significant changes in cervical spine joint kinetics during flexion provide mechanical evidence linking posture to neck pain.
  • Findings support the hypothesis of increased loading in 'text neck' postures.
  • Results emphasize the need for ergonomic interventions, such as optimal workstation and monitor setup.