Extremely low wear rates in hip joint bearings coated with nanocrystalline diamond

The nanocrystalline diamond films were deposited by microwave plasma enhanced chemical vapour deposition (PE-CVD) on Si (100) substrate. Reciprocating sliding tests were conducted using Si3N4 balls as a counter body. A method based on the construction of the Abbott curve representing the areas of pristine and worn surface in the wear scars was applied for estimation of the wear rate. The calculated wear rates were compared with the results obtained by profilometric measurements and direct measurement of the wear scars cross sections by scanning electron microscopy (SEM).

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Fretting Behavior of Coated and Treated Titanium Alloy Using an Open-Loop System

World Tribology Congress III, Volume 2 ◽

10.1115/wtc2005-63531 ◽

2005 ◽

Author(s):

G. R. Yantio Njankeu ◽

J.-Y. Paris ◽

J. Denape ◽

L. Pichon ◽

J.-P. Rivie`re

Keyword(s):

Titanium Alloy ◽

Relative Motion ◽

High Frequency ◽

Open Loop ◽

Loop System ◽

Test Apparatus ◽

Open Loop System ◽

Wear Rates ◽

Low Wear

Titanium alloys are well known to present poor sliding behaviour and high wear values. Various coatings and treatments have been tested to prevent such an occurrence under fretting conditions at high frequency of displacement (100 Hz). An original test apparatus, using an open-loop system instead of a classical imposed displacement simulator, has been performed to directly display the phenomenon of seizure, defined as the stopping of the relative motion between the contacting elements. A classification of the tested coatings has been proposed on the basis of their capacity to maintain full or partial sliding conditions, to present low wear rates and to prevent seizure.

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A Tracer Method to Determine Extremely Low Wear Rates of Ultrahigh Molecular Weight Polyethylene

Journal of ASTM International ◽

10.1520/jai100253 ◽

2006 ◽

Vol 3 (9) ◽

pp. 100253 ◽

Cited By ~ 4

Author(s):

J Kunze ◽

MA Wimmer

Keyword(s):

Molecular Weight ◽

Ultrahigh Molecular Weight Polyethylene ◽

Tracer Method ◽

Wear Rates ◽

Ultrahigh Molecular Weight ◽

Low Wear

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Load Scenarios Influence Fluid Absorption of Polyethylene

World Tribology Congress III, Volume 2 ◽

10.1115/wtc2005-63578 ◽

2005 ◽

Author(s):

T. Schwenke ◽

C. Rieker ◽

M. A. Wimmer

Keyword(s):

Wear Testing ◽

Fluid Absorption ◽

Joint Replacements ◽

Wear Rates ◽

Total Joint Replacements ◽

Fluid Uptake ◽

Dynamically Loaded ◽

Low Wear ◽

Lubrication Conditions

Wear of total joint replacements is determined gravimetrically in simulator studies. A mix of bovine serum, distilled water, and additives is intended to replicate the lubrication conditions in-vivo. Weight gain due to fluid absorption during testing of UHMWPE components is corrected using a load soak station. In this study six sets of UHMWPE pins were tested for their fluid soak behavior. The samples were subjected to three different loading scenarios while being submersed in two types of commonly used lubricants. After two million cycles or 23.1 days, respectively, the different fluids lead to significantly different soaking results. Test groups that were dynamically loaded gained more weight than unloaded or statically loaded samples. The results suggest that dynamically loaded soak control stations are required during wear testing of UHMWPE components. Otherwise the fluid uptake masks the wear measurement, especially for new polyethylene materials with low wear rates. Furthermore, an agreement on detailed lubricant specifications is desirable.

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Advanced wear of an Oxinium™ femoral head implant following polyethylene liner dislocation

Annals of The Royal College of Surgeons of England ◽

10.1308/rcsann.2013.95.8.e4 ◽

2013 ◽

Vol 95 (8) ◽

pp. e4-e6 ◽

Cited By ~ 2

Author(s):

H Tribe ◽

S Malek ◽

J Stammers ◽

V Ranawat ◽

JA Skinner

Keyword(s):

Femoral Head ◽

Surface Coating ◽

Hip Dislocation ◽

Acetabular Cup ◽

Revision Procedure ◽

Wear Rates ◽

Soft Metal ◽

Low Wear

Oxinium™ (Smith & Nephew, Memphis, TN, US) has been used in hip arthroplasty since 2003. The surface coating is hard and provides low wear rates but if this surface coating is damaged, the soft metal core is at risk of accelerated wear. Previous reports have described accelerated wear following intra and postoperative hip dislocation. We report a case of advanced wear of an in situ Oxinium™ femoral head implant following a cracked acetabular liner. The liner had disengaged from the titanium shell, allowing the Oxinium™ head to articulate directly with the shell. The disengaged liner led to dislocation of the Oxinium™ head, with associated pronounced wear of the head and the acetabular cup. The patient had a successful revision procedure. We advise close follow-up of patients with Oxinium™ implants, especially if associated with dislocation and closed reduction.

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Tribological assessment of a flexible carbon-fibre-reinforced poly(ether—ether—ketone) acetabular cup articulating against an alumina femoral head

Proceedings of the Institution of Mechanical Engineers Part H Journal of Engineering in Medicine ◽

10.1243/09544119jeim334 ◽

2008 ◽

Vol 222 (3) ◽

pp. 273-283 ◽

Cited By ~ 49

Author(s):

S C Scholes ◽

I A Inman ◽

A Unsworth ◽

E Jones

Keyword(s):

Wear Rate ◽

Carbon Fibre ◽

Acetabular Component ◽

Volumetric Wear ◽

Wear Rates ◽

Lubrication Regime ◽

Ether Ether Ketone ◽

Poly Ether Ether Ketone ◽

Ether Ketone ◽

Low Wear

New material combinations have been introduced as the bearing surfaces of hip prostheses in an attempt to prolong their life by overcoming the problems of failure due to wear-particle-induced osteolysis. This will hopefully reduce the need for revision surgery. The study detailed here used a hip simulator to assess the volumetric wear rates of large-diameter carbon-fibre-reinforced pitch-based poly(ether—ether—ketone) (CFR-PEEK) acetabular cups articulating against alumina femoral heads. The joints were tested for 25×106 cycles. Friction tests were also performed on these joints to determine the lubrication regime under which they operate. The average volumetric wear rate of the CFR-PEEK acetabular component of 54 mm diameter was 1.16 mm3/106 cycles, compared with 38.6 mm3/106 cycles for an ultra-high-molecular-weight polyethylene acetabular component of 28 mm diameter worn against a ceramic head. This extremely low wear rate was sustained over 25×106 cycles (the equivalent of up to approximately 25 years in vivo). The frictional studies showed that the joints worked under the mixed—boundary lubrication regime. The low wear produced by these joints showed that this novel joint couple offers low wear rates and therefore may be an alternative material choice for the reduction of osteolysis.

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Low Wear Rates Seen in THAs With Highly Crosslinked Polyethylene at 9 to 14 Years in Patients Younger Than Age 50 Years

Clinical Orthopaedics and Related Research ◽

10.1007/s11999-015-4422-7 ◽

2015 ◽

Vol 473 (12) ◽

pp. 3829-3835 ◽

Cited By ~ 32

Author(s):

Kevin L. Garvin ◽

Tyler C. White ◽

Anand Dusad ◽

Curtis W. Hartman ◽

John Martell

Keyword(s):

Wear Rates ◽

Low Wear

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The influence of shape and sliding distance of femoral head movement loci on the wear of acetabular cups in total hip arthroplasty

Proceedings of the Institution of Mechanical Engineers Part H Journal of Engineering in Medicine ◽

10.1243/095441102321032184 ◽

2002 ◽

Vol 216 (6) ◽

pp. 393-402 ◽

Cited By ~ 14

Author(s):

D Bennett ◽

J F Orr ◽

D E Beverland ◽

R Baker

Keyword(s):

Femoral Head ◽

Aspect Ratio ◽

Hip Joint ◽

Wear Rates ◽

Total Hip ◽

Aspect Ratios ◽

Average Aspect Ratio ◽

Sliding Distance

Wear of the polyethylene acetabular component is the most serious threat to the long-term success of total hip replacements (THRs). Greatly reduced wear rates have been reported for unidirectional, compared to multidirectional, articulation in vitro. This study considers the multidirectional motions experienced at the hip joint as described by movement loci of points on the femoral head for individual THR patients. A three-dimensional computer program determined the movement loci of selected points on the femoral head for THR patients and normal subjects using kinematic data obtained from gait analysis. The sizes and shapes of these loci were quantified by their sliding distances and aspect ratios with substantial differences exhibited between individual THR patients. The average sliding distances ranged from 10.0 to 18.1 mm and the average aspect ratios of the loci ranged from 2.5 to 9.2 for the THR patients. Positive correlations were found between wear rate and average sliding distance, the inverse of the average aspect ratio of the loci and the product of the average sliding distance and the inverse of the average aspect ratio of the loci. Patients with a normal hip joint range of motion produce multidirectional motion loci and tend to experience more wear than patients with more unidirectional motion loci. Differing patterns of multidirectional motion at the hip joint for individual THR patients may explain widely differing wear rates in vivo.

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