Age and gender differences in lumbar intervertebral disk strain using mechanical loading magnetic resonance imaging

Area of Science:

• Biomedical Engineering
• Radiology
• Orthopedics

Background:

• Lumbar intervertebral disk (IVD) degeneration is a common issue associated with aging.
• Understanding age-related mechanical changes in IVDs is crucial for developing effective interventions.

Purpose of the Study:

• To investigate age- and gender-related differences in lumbar IVD strain.
• To assess the mechanical properties of lumbar IVDs under static loading using advanced MRI techniques.

Main Methods:

• Utilized continuous 3D golden-angle radial sparse parallel (GRASP) MRI on a 3-T scanner with static mechanical loading.
• Calculated motion deformation and Lagrangian strain maps in X, Y, and Z directions for lumbar IVD segments.
• Correlated age with IVD height and strain using Spearman coefficients and compared gender differences with Mann-Whitney tests.

Main Results:

• Significant increases in compressive strain were observed with age, particularly in the X-direction during loading and recovery (negative correlation).
• No significant correlation was found between age and IVD height, or strain in the Y and Z directions.
• No significant gender-based differences in IVD height or strain were detected.

Conclusions:

• Aging plays a significant role in the dynamic strains within the lumbar IVD.
• Older individuals exhibit reduced IVD stiffness and increased compression during mechanical loading.
• GRASP-MRI is a feasible technique for identifying age-related changes in IVD mechanical properties, indicative of early degeneration.