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Updated: Aug 15, 2026
08:43
Potentiodynamic Corrosion Testing
Published on: September 4, 2016
Nonconsolidated polyethylene particles and oxidation in Charnley acetabular cups
1Department of Biomechanics and Biomaterials, Hospital for Special Surgery, New York, NY 10021, USA.
Clinical Orthopaedics and Related Research
|October 1, 1995
Summary
Ultra-high molecular weight polyethylene particles are common in joint replacements but do not correlate with wear performance. Their presence in new implants relates to radiation sterilization time, not necessarily immediate adverse effects.
Area of Science:
- Biomaterials Science
- Orthopedic Surgery
- Materials Science
Background:
- Nonconsolidated ultra-high molecular weight polyethylene (UHMWPE) particles are implicated as defects affecting joint prosthesis wear.
- The origin and impact of these particles on implant performance remain incompletely understood.
Purpose of the Study:
- To quantify the number, size, and distribution of UHMWPE particles in retrieved and new acetabular components.
- To investigate correlations between particle presence and wear performance, clinical outcomes, and implant parameters.
Main Methods:
- Light microscopy analysis of thin cross-sections from 40 retrieved and 7 new acetabular components.
- Examination of particle distribution (random vs. banded) and density.
Main Results:
- Particles were found in 92% of retrieved and 100% of new components.
- No correlation was observed between particle load and wear performance or clinical/implant variables.
- Particle presence in new implants correlated with time since radiation sterilization.
- Higher density (oxidative degradation) was noted in banded particle regions of retrieved components and with longer times since sterilization in new components.
Conclusions:
- Nonconsolidated UHMWPE particles are prevalent in total joint replacements but do not appear to correlate with acetabular cup implantation duration.
- While not directly linked to wear in this study, banded particles in high-stress areas (e.g., knee replacements) may still pose a risk to implant performance.
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