Risk of Complication and Revision Total Hip Arthroplasty Among Medicare Patients with Different Bearing Surfaces

Department of Orthopaedic Surgery, University of California, San Francisco, CA 94143-0728, USA.
Clinical Orthopaedics and Related Research (Impact Factor: 2.77). 02/2010; 468(9):2357-62. DOI: 10.1007/s11999-010-1262-3
Source: PubMed


To address the long-term problems of bearing surface wear and osteolysis associated with conventional metal-polyethylene (M-PE) total hip arthroplasty (THA), metal-metal (M-M), and ceramic-ceramic (C-C) bearings have been introduced. These bearing surfaces are associated with unique risks and benefits and higher costs. However the relative risks of these three bearings in an older population is unknown.
We compared the short-term risk of complication and revision THA among Medicare patients having a primary THA with metal-polyethylene (M-PE), metal-metal (M-M), and ceramic-ceramic (C-C) bearings.
We used the 2005 to 2007 100% Medicare inpatient claim files to perform a matched cohort analysis in three separate cohorts of THA patients (M-PE, M-M, and C-C) who were matched by age, gender, and US census region. Multivariate Cox proportional-hazards models were constructed to compare complication and revision THA risk among cohorts, adjusting for medical comorbidities, race, socioeconomic status, and hospital factors.
After adjusting for patient and hospital factors, M-M bearings were associated with a higher risk of periprosthetic joint infection (hazard ratio, 3.03; confidence interval, 1.02-9.09) when compared with C-C bearings (0.59% versus 0.32%, respectively). There were no other differences among bearing cohorts in the adjusted risk of revision THA or any other complication.
The risk of short-term complication (including dislocation) and revision THA were similar among appropriately matched Medicare THA patients regardless of bearing surface. Hard-on-hard THA bearings are of questionable value in Medicare patients, given the higher cost associated with their use and uncertain long-term benefits in older patients.
Level II, prognostic study. See Guidelines for Authors for a complete description of levels of evidence.

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    • "It is now ranked among the most common surgical operations performed worldwide, with over one million procedures estimated to be carried out annually [2], [3]. Over the past few decades, metal-on-metal hip devices gained popularity, and up to recently accounted for approximately 14% of all THRs in England and Wales [4], [5]. The use of these devices, which have been associated with the widespread dissemination of metal ions including cobalt and chromium [6], has raised a number of health concerns, including the potential risk of cancer [7], [8]. "
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    ABSTRACT: There are concerns that metal-on-metal hip implants may cause cancer. The objective of this study was to evaluate patterns and timing of risk of cancer in patients with metal-on-metal total hip replacements (THR). In a linkage study between the English National Joint Registry (NJR) and the Clinical Practice Research Datalink (CPRD), we selected all THR surgeries (NJR) between 2003 and 2010 (n = 11,540). THR patients were stratified by type of bearing surface. Patients were followed up for cancer and Poisson regression was used to derive adjusted relative rates (RR). The risk of cancer was similar in patients with hip resurfacing (RR 0.69; 95% Confidence Interval [CI] 0.39-1.22) or other types of bearing surfaces (RR 0.96; 95% CI 0.64-1.43) compared to individuals with stemmed metal-on-metal THR. The pattern of cancer risk over time did not support a detrimental effect of metal hip implants. There was substantial confounding: patients with metal-on-metal THRs used fewer drugs and had less comorbidity. Metal-on-metal THRs were not associated with an increased risk of cancer. There were substantial baseline differences between the different hip implants, indicating possibility of confounding in the comparisons between different types of THR implants.
    Full-text · Article · Jul 2013 · PLoS ONE
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    • "However, the durability of MoM implants, biological reaction of metallic wear debris with the surrounding tissues and toxic metal deposit in blood have been significant challenges [1] [2] [3]. The UK National Joint Registry [1] reported 8,309 revision procedures between 2008 and 2010 in England alone. Textured bearing surfaces produce lower wear rates than non-textured surfaces due to reduced contact surface areas, reduced friction coefficients and removal of wear debris, which further reduce surface wear [4] [5] [6] [7] [8]. "
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    ABSTRACT: Wear rate and debris are key problems to implanted metal-on-metal hip joints. Surface texture on bearing surfaces is reported to increase tribological performances. Research on the translation of this technology to metal-on-metal hip joint for reduction of friction, wear rate and debris generation is limited. The aim of this study was to investigate, by theoretical predictions and experimental investigations, the tribological properties of simulated metal-on-metal hip joints with different surface textures. Three different honed surfaces were produced with emery paper at controlled load and speed. The experiments were carried out using a computer-controlled friction simulator. Theoretical prediction was carried out using an existing model for textured surfaces. Both experimental and theoretical results demonstrated that honed surfaces had lower friction coefficients during walking and stairs ascent and descent, demonstrating their potential use in metal on metal hip joints for increased implant longevity.
    Full-text · Article · Apr 2013 · Tribology Online
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    • "At the same time, several MOM THAs made of cobalt-chromium were reintroduced with the same claim that the new high-precision production methods should give less friction than the LFA. In the USA in 2009, approximately one third of the hip joint procedures were large MOM articulations (Bozic et al. 2010). "
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    ABSTRACT: Abstract This is a review of the hip arthroplasty era. We concentrate on new metal bearings, surface replacements, and the lessons not learned, and we highlight recent reports on malignancies and joint implants. A low incidence of blood malignancies has been found in bone marrow taken at prosthetic surgery. The incidence is increased after replacement with knee implants that release very low systemic levels of metal ions. A carcinogenic effect of the high levels of metal ions released by large metal-on-metal implants cannot be excluded. Ongoing Swedish implant registry studies going back to 1975 can serve as a basis for evaluation of this risk.
    Full-text · Article · Nov 2012 · Acta Orthopaedica
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