A Mouse Intervertebral Disc Degeneration Model by Surgically Induced Instability.

Area of Science:

• Orthopedics and Regenerative Medicine
• Spinal Research
• Animal Models in Disease Study

Background:

• Intervertebral disc degeneration (IDD) lacks a standardized mouse model without direct disc injury.
• Existing models often involve invasive procedures, limiting their applicability for studying native IDD pathophysiology.

Purpose of the Study:

• To develop a reproducible mouse model of lumbar intervertebral disc degeneration (IDD).
• To validate the model by comparing its radiological and histological features with human IDD.

Main Methods:

• Surgically induced lumbar spine instability in 59 C57BL/6J male mice via posterior element resection.
• Time-course analysis of radiographical and histological changes over 12 weeks.
• Comparison of induced changes with established human IDD characteristics.

Main Results:

• Progressive disc height reduction and vertebral bone spur formation observed post-surgery.
• Histological analysis revealed anterior anulus fibrosus disorder, nucleus pulposus degeneration, and proteoglycan decrease.
• Increased collagen types I and X, and matrix metalloproteinase 13 in the anterior anulus fibrosus.

Conclusions:

• Surgical induction of lumbar spine instability creates a reproducible mouse model of IDD.
• The model's non-invasive nature (to the disc itself) and human-like pathology make it suitable for studying IDD.
• This model holds potential for advancing the understanding of intervertebral disc degeneration's native pathophysiology.