ESTABLISHING A LIVE CARTILAGE-ON-CARTILAGE INTERFACE FOR TRIBOLOGICAL TESTING

Area of Science:

• Biomaterials Science
• Orthopedics
• Biomechanics

Background:

• Mechano-biochemical wear describes cartilage degradation from biological and mechanical factors.
• Current testing systems do not fully replicate the natural joint environment.

Purpose of the Study:

• To develop and validate a novel tribological testing system for studying cartilage mechano-biochemical wear.
• To compare cartilage-on-cartilage (CoC) and metal-on-cartilage (MoC) bearing systems.
• To assess the effect of tissue viability on cartilage wear.

Main Methods:

• A novel tribological testing rig was designed to mimic the joint environment with live cartilage interfaces and controlled mechanical stimuli.
• Bovine cartilage explants were tested for three days in CoC and MoC configurations.
• Wear was quantified by glycosaminoglycan release and tissue structure evaluation.

Main Results:

• MoC articulation caused significant cartilage damage, including decreased cell viability and extracellular matrix disruption, compared to CoC.
• Live and dead CoC articulations showed similar wear rates, but live CoC exhibited higher glycosaminoglycan biosynthesis, indicating stimulated cell activity.
• The novel system demonstrated effectiveness in differentiating wear between bearing types.

Conclusions:

• The developed tribological testing system adequately simulates joint conditions and can differentiate wear between CoC and MoC interfaces.
• The system is suitable for screening biomaterials intended for cartilage articulation, such as in hemiarthroplasty.
• While tissue viability may not be critical for short-term wear measurement, it influences cellular activity and biosynthesis, warranting further investigation into mechano-biochemical wear mechanisms.