Related Experiment Video
Updated: May 31, 2026
08:03
An In Vitro Organ Culture Model of the Murine Intervertebral Disc
Published on: April 11, 2017
10.2K
Interlamellar-induced time-dependent response of intervertebral disc annulus: A microstructure-based
Karim Kandil1, Fahmi Zaïri2, Amil Derrouiche2
1Lille University, Lille Mechanics Unity (EA 7512 UML), 59000 Lille, France; Lille University, Civil Engineering and geo-Environmental Laboratory (EA 4515 LGCgE), 59000 Lille, France.
Acta Biomaterialia
|October 7, 2019
Summary
A new model explains the annulus fibrosus
Area of Science:
- Biomechanics
- Biomaterials Science
- Computational Biology
Background:
- The annulus fibrosus, a key component of the intervertebral disc, exhibits complex behavior.
- Existing models do not fully capture its regional effects, chemical sensitivity, and time-dependent properties.
Purpose of the Study:
- To develop a physically-based, microstructure-informed model of the annulus fibrosus.
- To account for regional variations, biochemical environment, and time-dependent viscoelasticity.
Main Methods:
- A free energy function was formulated considering tissue structure and biochemical factors.
- A finite element model incorporated the interlamellar ground substance.
- Full-field strain measurements were used to validate the model's kinetics under varying osmotic conditions.
Main Results:
- The model successfully reproduced the annulus fibrosus's unusual transversal behavior and regional dependency.
- Observed Poisson's ratios ranged from negative (auxetic) to above 0.5, converging to typical values over time.
- The interlamellar zone's role in time-dependent responses was elucidated.
Conclusions:
- The developed chemo-viscoelastic model accurately predicts annulus fibrosus macro-responses.
- It provides critical insights into the origins of time-dependent phenomena and regional variations.
- This understanding is vital for intervertebral disc functionality and health.
Keywords:
Annulus fibrosusExtracellular matrix viscosityFinite element computationMicrostructureOsmo-induced transversal responseRegional dependencyMore Related Videos
Related Concept Videos
01:29Herniated Intervertebral Disc l: Introduction
Intervertebral disc herniation refers to the displacement of the nucleus pulposus (the gel-like inner core of the disc) through a tear or weakened area in the annulus fibrosus (the outer fibrous ring). The displaced disc material extends beyond the normal boundaries of the disc space and may compress or irritate nearby spinal nerve roots or, less commonly, the spinal cord.Etiology and Risk FactorsHerniation commonly results from degeneration, in which aging reduces disc hydration and...
01:27Degenerative Disc Disease I: Introduction
Degenerative disc disease is a chronic condition in which intervertebral discs gradually lose structure and function. It is not infectious or autoimmune; rather, it results from age-related biochemical and mechanical changes, influenced by genetic, metabolic, and environmental factors.Structure and Function of DiscsThe spine contains 23 intervertebral discs that absorb load, distribute forces, maintain spacing, and allow flexibility. Each disc consists of a nucleus pulposus, a gel-like core...
01:23Degenerative Disc Disease ll: Pathophysiology
The symptoms of degenerative disc disease arise from a combination of mechanical compression, vascular compromise, and biochemical inflammation, which together disrupt nerve function and produce pain.Mechanical CompressionDisc degeneration reduces height and elasticity, predisposing to herniation of the nucleus pulposus, a major cause of radicular pain. Herniations may be protrusion (bulging with intact annulus), extrusion (nucleus extends beyond disc but remains connected), or sequestration...