Failure of the Durom Metasul® Acetabular Component

Background Few large series of hard bearing surfaces have reported on reasons for early failure. A number of unique mechanisms of failure, including fracture, squeaking, and adverse tissue reactions, have been reported with these hard bearing surfaces. However, the incidence varies among the published studies. Questions/purposes To confirm the incidences, we identified the etiologies of early failures of hard-on-hard bearing surfaces for ceramic-on-ceramic and metal-onmetal THAs. Methods We retrospectively reviewed records of 2907 THAs with hard-on-hard bearing surfaces implanted between 1996 and 2009; 1697 (58%) had ceramic-onceramic and 1210 (42%) had metal-on-metal bearing surfaces. We recorded bearing-related complications and compared them to nonspecific reasons for revision THA. The minimum followup of the ceramic-on-ceramic and metal-on-metal cohorts was 6 months (mean, 48 months; range, 6-97 months) and 24 months (mean, 60 months; range, 24-178 months), respectively. Results The overall revision rate for ceramic-on-ceramic THA was 2.2% (38 of 1697), with aseptic loosening accounting for 55% of revisions (femur or acetabulum). The bearing accounted for 13% of the revisions in the ceramic-on-ceramic THA cohort. The overall metal-onmetal revision rate was 5.4% (65 of 1210), 17 involving adverse tissue reactions related to the metal-on-metal bearing surface (17 of 1210, 1.4% of cases; 17 of 65, 26% of revisions). Conclusions Twenty-six percent of the revisions from metal-on-metal and 13% of ceramic-on ceramic were bearing related. The overall short-to medium-term revision rate was 2.2% and 5.4% for ceramic-on-ceramic and metalon-metal, respectively. The most common etiology of failure was loosening of the femoral or acetabular components.

Section: Discussionmentioning

confidence: 93%

Causes of Failure of Ceramic-on-Ceramic and Metal-on-Metal Hip Arthroplasties

Porat

Parvızı

Sharkey

et al. 2012

“…Finally, patients in this retrieval study may not have represented the general population of patients with MOM hip prostheses. Therefore, we compared our patient population with the largest published single-center series of patients with current-generation MOM hip prostheses [4,20,29,40,43] (Table 4). We also compared the outcome variables of this study with all of the published retrieval studies of current-generation MOM hip implants [10,14,22,25,30,32,41] (Table 5).…”

Section: Discussionmentioning

confidence: 99%

Pseudotumors Are Common in Well-positioned Low-wearing Metal-on-Metal Hips

Matthies

Skinner

Osmani

et al. 2012

141

138

Background Pseudotumors are sterile inflammatory lesions found in the soft tissues surrounding metal-on-metal (MOM) and metal-on-polyethylene hip arthroplasties. In patients with MOM hip arthroplasties, pseudotumors are thought to represent an adverse reaction to metal wear debris. However, the pathogenesis of these lesions remains unclear. Currently, there is inconsistent evidence regarding the influence of adverse cup position and increased wear in the formation of pseudotumors. Questions/purposes We therefore determined whether pseudotumor formation was associated with (1) adverse cup position, (2) raised metal ion levels, and (3) increased wear rates of the retrieved components. Methods We retrospectively reviewed all 352 patients for whom we had retrieved specimens from revisions of a current-generation MOM hip prosthesis between February 2008 and September 2010; of these, 105 met our inclusion criteria. We used multivariate logistic regression analysis to compare acetabular orientation, metal ion levels before revision, and component wear rates between patients with (n = 72) and without (n = 33) pseudotumors, according to findings on metal artifact reduction sequence MRI. Results The proportion of patients demonstrating evidence of a pseudotumor in well-positioned hips was similar to those with adverse cup positions (67% and 66%, respectively). Patients revised with pseudotumors had similar whole-blood metal ion levels and component wear rates to those who were not revised. Conclusions Pseudotumors were not associated with increased wear or metal ion levels, suggesting patient susceptibility is likely to be more important.

“…Conversely, three original reports using the Durom HRA reported revisions in only 2.3% to 3.5% at a short-term followup [11,13,14]. The Durom resurfacing prosthesis, which differs in the design and manufacturing process from the large-diameter head metal-on-metal THA device made in the US that was associated with high failure rates [21], was launched and approved for HRA in Europe and Australia in 2003. At our institution, the Durom HRA (Zimmer, Winterthur, Switzerland) has been implanted since it became available to us.…”

Section: Introductionmentioning

confidence: 99%

High Revision Rate at 5 Years after Hip Resurfacing with the Durom Implant

Naal

Pilz

Munzinger

et al. 2011

Background/rationale There is growing evidence that different resurfacing implants are associated with variable survival and revision rates. A registry analysis indicated the Durom resurfacing implant had high revision rates at 5 years, whereas three original studies reported low revision rates at short-term followups. Thus, the revision rates appear controversial. Questions/purposes We therefore assessed (1) the survivorship including differences between women and men at a mean of 5 years after resurfacing with the Durom implant, and (2) clinical scores and radiographic parameters. Patients and Methods We prospectively followed all 100 Durom hip resurfacings implanted in 91 patients (25 women and 66 men; mean age, 52 years) between 2003 and 2004. Survivorship analysis was performed with pending revision or revision for any reason as the endpoint. The minimum followup was 47 months (mean, 60 months; range, 47-72 months).Results At a mean of 5 years, 11 hips were revised for various reasons. Cumulative survival was 88.2% for all patients and 81.5% for women. The mean Oxford (OHS) and Harris hip (HHS) scores were 14.6 and 94.7, respectively. The mean UCLA activity level was 7.9. Sclerotic changes around the short femoral stem (pedestal sign) were detected in 40% of the hips. We observed considerable femoral neck thinning with component-to-neck ratios of 0.85 preoperatively and 0.82 at 5 years. Conclusions Our study highlights a high revision rate 5 years after hip resurfacing with the Durom implant. This observation underlines previous findings from registry data and suggests that revision rates increase with time.