A Systematic Review and Guide to Mechanical Testing for Articular Cartilage Tissue Engineering

Area of Science:

• Biomedical Engineering
• Orthopedic Research
• Materials Science

Background:

• Articular cartilage is crucial for joint function but has limited self-healing capacity.
• Cartilage injuries necessitate therapies and replacements, requiring rigorous mechanical evaluation.
• Existing mechanical testing protocols for cartilage are diverse, hindering inter-study comparisons.

Purpose of the Study:

• To systematically review mechanical testing methods for articular cartilage and repair constructs (2009-2018).
• To identify common testing configurations and key parameters.
• To validate findings by characterizing native cartilage and engineered hydrogels.

Main Methods:

• Systematic literature review of mechanical testing studies on articular cartilage and constructs.
• Analysis of common testing configurations (compression, friction) and parameters (strain rate, equilibrium time).
• Validation of key parameters through experimental characterization of cartilage tissue and hydrogels.

Main Results:

• Compression testing was the most prevalent method (80.2%).
• Significant variability was observed in testing modes, configurations, and parameters.
• Variations in testing criteria demonstrably impact outcome parameters like modulus.

Conclusions:

• Standardization of mechanical testing protocols is crucial for reliable data interpretation in cartilage tissue engineering.
• This review provides a guide for selecting and applying appropriate mechanical evaluation methods.
• Consistent methodologies will enhance the comparison and advancement of cartilage repair strategies.