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Polyurethane unicondylar knee prostheses: simulator wear tests and lubrication studies
S C Scholes1, A Unsworth, E Jones
1Centre for Biomedical Engineering, Durham University, DH1 3LE, UK. s.c.scholes@durham.ac.uk
Physics in Medicine and Biology
|December 22, 2006
Summary
New polycarbonate urethane (PU) knee prostheses show significantly lower wear and friction than traditional materials. These artificial joints promote fluid film lubrication, offering a promising alternative for improved joint replacement longevity.
Area of Science:
- Biomaterials Science
- Orthopedic Engineering
- Tribology
Background:
- Conventional artificial joint materials like metal-on-polyethylene have limited lifespans, necessitating revision surgery.
- Existing bearing surfaces often fail due to wear and suboptimal lubrication, impacting prosthesis longevity.
Purpose of the Study:
- To evaluate the tribological performance of novel Cobalt-Chromium-Molybdenum (CoCrMo)-on-polycarbonate urethane (PU) knee prostheses.
- To assess if CoCrMo-on-PU can mimic natural synovial joint lubrication and reduce wear compared to conventional materials.
Main Methods:
- In vitro tribological testing of CoCrMo-on-PU unicondylar knee prostheses.
- Assessment of wear, friction, and lubrication regimes under simulated physiological conditions.
Main Results:
- CoCrMo-on-PU components exhibited significantly lower wear rates than conventional artificial joints.
- Low friction and operation near full-fluid film lubrication were observed.
- Lubricant viscosities in tests mimicked those found in patients with arthritis.
Conclusions:
- Polycarbonate urethane demonstrates encouraging tribological performance as an artificial joint bearing surface.
- The CoCrMo-on-PU combination shows potential as an alternative bearing material for improved joint replacement outcomes.
- Further research into PU-based prostheses could lead to enhanced longevity and reduced revision surgery rates.
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