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A Proinflammatory, Degenerative Organ Culture Model to Simulate Early-Stage Intervertebral Disc Disease.
Published on: February 14, 2021
Torsion-induced pressure distribution changes in human intervertebral discs: an in vitro study
Brenda K Yantzer1, Thomas B Freeman, William E Lee
1Department of Neurological Surgery and Rehabilitation, University of South Florida, Tampa, FL, USA.
Spine
|April 12, 2007
Summary
Small amounts of twisting force on human lumbar spine specimens did not significantly change intradiscal pressure or disc height. These findings suggest spinal manipulation may not relieve low back pain through this biomechanical mechanism.
Area of Science:
- Biomedical Engineering
- Spine Biomechanics
- Orthopedics
Background:
- Previous research on porcine spines indicated that small axial vertebral rotations could decrease intradiscal pressure and increase disc height.
- This phenomenon, if applicable to humans, could potentially explain the therapeutic effects of spinal manipulation for low back pain.
Purpose of the Study:
- To investigate the biomechanical effects of small-magnitude torsional torques on intradiscal pressure and disc height in human lumbar cadaveric specimens.
- To determine if axial vertebral rotations influence spinal mechanics in a way that could support spinal manipulation therapies.
Main Methods:
- Biomechanical testing was conducted on six human lumbar functional spine units (FSUs) under 600 N axial compression.
- Intradiscal pressure and disc height were measured at varying torsion torques (0-2.0 Nm) before and after removal of posterior elements to analyze the disc body unit (DBU).
Main Results:
- No statistically significant differences in intradiscal pressure or disc height were observed across different torsion torques in either FSUs or DBUs.
- A minor disc height increase (0.13-0.16 mm) was noted, attributed to the insertion of the pressure probe cannula.
Conclusions:
- The application of small torsion torques to human lumbar specimens does not significantly alter intradiscal pressures or disc heights.
- The study suggests that the biomechanical effects observed in porcine models are unlikely to be the mechanism behind the perceived benefits of spinal manipulation for low back pain.
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