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Updated: Jul 18, 2026
07:09
In situ Compressive Loading and Correlative Noninvasive Imaging of the Bone-periodontal Ligament-tooth Fibrous Joint
Published on: March 7, 2014
Peak stresses observed in the posterior lateral anulus
W T Edwards1, N R Ordway, Y Zheng
1Department of Physical Medicine and Rehabilitation, SUNY Upstate Medical University, Syracuse, NY 13210, USA. edwardst@mail.upstate.edu
Spine
|August 9, 2001
Summary
Peak stress in the lumbar spine
Area of Science:
- Biomechanics of the spine
- Spinal loading and degeneration
Background:
- Spinal loading increases disc degeneration and low back disorders.
- The anulus experiences the highest peak stresses.
Purpose of the Study:
- To examine stress distribution in cadaveric lumbar intervertebral discs.
- To compare regional stress variations under compression with flexion.
Main Methods:
- Tested human lumbar functional spinal units (L2-L3, L4-L5).
- Measured disc stress distribution using a pressure probe.
- Applied compression with varying flexion/extension angles.
Main Results:
- Highest stresses (2.99 MPa) occurred in the posterior anulus during extension-compression.
- Nucleus pressure remained stable (~1.00 MPa) under 1000-N compression.
- Stress profiles varied with flexion angle.
Conclusions:
- Posterolateral anulus stress sites correlate with disc degeneration and herniation.
- Findings validate lumbar spine loading models.
- Identifies high-stress regions beyond midsagittal nucleus measurements.
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