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Ovine Lumbar Intervertebral Disc Degeneration Model Utilizing a Lateral Retroperitoneal Drill Bit Injury
Published on: May 25, 2017
Dynamic and static overloading induce early degenerative processes in caprine lumbar intervertebral discs.
Cornelis P L Paul1, Tom Schoorl, Hendrik A Zuiderbaan
1Department of Orthopaedic Surgery, VU University Medical Center, Amsterdam, The Netherlands.
Plos One
|May 3, 2013
Summary
Mechanical overloading causes intervertebral disc (IVD) degeneration through different pathways depending on whether the load is static or dynamic. Understanding these distinct mechanisms is key to developing new therapies for degenerative disc disease (DDD).
Area of Science:
- Biomedical Engineering
- Orthopedics
- Cell Biology
Background:
- Mechanical overloading of the spine is a known risk factor for low back pain and intervertebral disc (IVD) degeneration.
- The precise mechanisms by which excessive loading induces degenerative changes in the IVD remain incompletely understood.
- Detailed knowledge of the interplay between mechanical loading, cellular responses, and extracellular matrix alterations is crucial for effective therapeutic interventions.
Purpose of the Study:
- To investigate the differential effects of dynamic versus static overloading on caprine lumbar discs.
- To elucidate the specific mechanisms underlying mechanically induced IVD degeneration under different loading conditions.
Main Methods:
- 175 caprine lumbar IVDs were cultured for 7, 14, and 21 days under simulated-physiological (control), high dynamic, or high static loading conditions.
- Continuous measurement of axial deformation and stiffness.
- Assessment of cell viability, cell density, and gene expression in nucleus, inner annulus, and outer annulus.
- Analysis of extracellular matrix (ECM) composition, including water, glycosaminoglycan, and collagen content.
Main Results:
- Static overloading caused acute IVD height loss and deformation, while dynamic overloading resulted in gradual changes.
- Dynamic overloading induced cell death across all IVD regions, whereas static overloading predominantly affected the outer annulus.
- Catabolic and inflammation-related gene expression was upregulated rapidly under both loading types.
- Significant loss of water and glycosaminoglycan content was observed only after 21 days of culture.
Conclusions:
- Both static and dynamic overloading induce pathological changes in caprine lumbar IVDs within 21 days.
- The biomechanical, cellular, and extracellular matrix changes differ significantly between static and dynamic overloading mechanisms.
- These findings offer insights into potential pharmacological and rehabilitative therapeutic targets for halting the progression of degenerative disc disease (DDD).
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