Near field effect on elasticity measurement for cartilage-bone structure using Lamb wave method.

Area of Science:

• Biomechanics
• Biomedical Engineering
• Medical Imaging

Background:

• Cartilage degeneration alters elasticity, suggesting elasticity detection for early osteoarthritis diagnosis.
• Shear wave elastography (SWE) is an emerging non-invasive method for elasticity detection.
• Accurate wave propagation models are essential for SWE, but cartilage models are lacking.

Purpose of the Study:

• To establish a wave propagation model for the cartilage-bone structure.
• To investigate elasticity measurement and wave propagation in cartilage-bone constructs.

Main Methods:

• Fabrication of a cartilage-bone structure.
• Experimental and numerical Lamb wave method (LWM) for elasticity measurement and wave propagation analysis.

Main Results:

• The developed wave propagation model aligns with Lamb wave theory for two-layered structures.
• A near-field region affecting wave speed was identified and characterized.
• A critical frequency was determined to mitigate the near-field effect on measurements.

Conclusions:

• The findings provide a theoretical basis for in vivo cartilage elasticity measurement using LWM.
• This work supports the application of LWM in diagnosing osteoarthritis.