THA using metal-on-metal articulation in active patients younger than 50 years.
ABSTRACT The main concern of patients with longer life expectancies and of patients who are younger and more active is the longevity of their total hip arthroplasty. We retrospectively reviewed 83 cementless total hip arthroplasties in 73 patients implanted with metal-on-metal articulation. All patients were younger than 50 years old (average age, 41 years) at the time of the index procedure, and 80% of the patients had an activity level graded 4 or 5 when measured with the system of Devane et al. A 28-mm Metasul articulation was used with three different cementless titanium acetabular components. At the most recent followup (average, 7.3 years), the average Merle d'Aubigné-Postel score improved from a preoperative 11.1 points to 17.4 points. We observed no radiographic evidence of component loosening. Ten acetabular components had lucency limited to one zone. The 10-year survivorship with the end point of revision (ie, exchange of at least one prosthetic or bearing component) was 100% (95% confidence interval, 90%-100%). Metasul bearings with cementless acetabular components remain promising in this high-risk younger patient population. However, additional followup strategies are recommended to determine any possible long-term deleterious effects associated with the dissemination of metallic ions. LEVEL OF EVIDENCE: Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.
Full-textDOI: · Available from: Philippe Clavert, Jan 06, 2014
SourceAvailable from: Joachim Kunze[Show abstract] [Hide abstract]
ABSTRACT: Due to the wear-related problems with large diameter metal-on-metal THA components, ion levels of cobalt and chromium in blood or serum are used to identify bearings with high-wear rates. Threshold levels for critical concentrations for these two alloys are published and quite frequently revised. Patients and doctors are confused, if measured values are close to thresholds. A new approach is presented by an international expert panel endorsed by EFFORT and several national organizations suggesting the use of a range instead of a specific value as threshold. This approach supports the philosophy that metal ion concentrations by themselves are not a diagnosis but one – important – piece in the assessment of a patient with a metal-on-metal hip articulation.Seminars in Arthroplasty 12/2012; 23(4):283-285. DOI:10.1053/j.sart.2012.12.002
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ABSTRACT: Background and purpose - The optimal hip replacement for young patients remains unknown. We compared patient-reported outcome measures (PROMs), revision risk, and implant costs over a range of hip replacements. Methods - We included hip replacements for osteoarthritis in patients under 60 years of age performed between 2003 and 2010 using the commonest brand of cemented, cementless, hybrid, or resurfacing prosthesis (11,622 women and 13,087 men). The reference implant comprised a cemented stem with a conventional polyethylene cemented cup and a standard-sized head (28- or 32-mm). Differences in implant survival were assessed using competing-risks models, adjusted for known prognostic influences. Analysis of covariance was used to assess improvement in PROMs (Oxford hip score (OHS) and EQ5D index) in 2014 linked procedures. Results - In males, PROMs and implant survival were similar across all types of implants. In females, revision was statistically significantly higher in hard-bearing and/or small-stem cementless implants (hazard ratio (HR) = 4) and resurfacings (small head sizes (< 48 mm): HR = 6; large head sizes (≥ 48 mm): HR = 5) when compared to the reference cemented implant. In component combinations with equivalent survival, women reported significantly greater improvements in OHS with hybrid implants (22, p = 0.006) and cementless implants (21, p = 0.03) (reference, 18), but similar EQ5D index. For men and women, National Health Service (NHS) costs were lowest with the reference implant and highest with a hard-bearing cementless replacement. Interpretation - In young women, hybrids offer a balance of good early functional improvement and low revision risk. Fully cementless and resurfacing components are more costly and do not provide any additional benefit for younger patients.Acta Orthopaedica 10/2014; 86(1):1-11. DOI:10.3109/17453674.2014.972256 · 2.45 Impact Factor
Revue de Chirurgie Orthopédique et Traumatologique 10/2014; DOI:10.1016/j.rcot.2014.09.277