| Autor: |
B.M. Wroblewski, Anthony Unsworth, I C Burgess, Richard M. Hall |
| Rok vydání: |
1994 |
| Předmět: |
|
| Zdroj: |
Wear. 175:159-166 |
| ISSN: |
0043-1648 |
| DOI: |
10.1016/0043-1648(94)90179-1 |
| Popis: |
The frictional resistances of 54 explanted and 5 new Charnley hip prostheses were measured using one of two Durham hip function simulators. The friction factor f was measured in both dry and lubricated environments up to a viscosity η of approximately 0.1 Pa s. The friction factor values for the new prostheses were found to be 0.11 (± 0.025) and 0.04 (±0.01) for dry and lubricated ( η = 0.01 Pa s) regimes respectively. The distributions of f for the new prostheses were found to be approximately Gaussian. However, the distributions for the explanted prostheses were skewed, with most retaining friction values similar to those of new prostheses, but a significant proportion exhibiting increased frictional resistance. For dry regimes 30% of the prostheses showed values of f in excess of 0.16, while for lubricated regimes ( η = 0.01 Pa s) 39% showed values of f greater than 0.07. All the joints indicated a mixed lubrication regime when analysed in terms of a Stribeck plot. A weak negative correlation ( P f is not the cause of the increased occurrence of loosening found with increased penetration in this type of prosthesis. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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