Page 108 - DOS Kongressen 2012 - Abstracts

68.
Catastrophic result with the metal-on-metal Conserve acetabular cup
Thomas Jakobsen, Hardy Christoffersen, Mette Adler Stampe, Anne Bensen,
Niels Krarup
Ortopædkirurgisk afdeling Regionshospitalet Viborg; Ortopædkirurgisk
afdeling, Sygehus Thy-Mors; Ortopædkirurgisk afdeling, Regionshospitalet
Viborg; Ortopædkirurgisk afdeling, Regionshospitalet Viborg;
Ortopædkirurgisk afdeling, Regionshospitalet Viborg
Background:
The metal-on-metal (MoM) bearing has previously been an
attractive option for young patients with the need of a total hip replacement.
Previous studies have shown promissing results using the MoM articulation.
However, current reports strongly indicate that the use of MoM is associated
with high failure rates, formation of pseudotumores, and elevated blood leveles
of metal ions.
Purpose / Aim of Study:
The aim of the study was to retrospective investigate
the survival of the MoM Conserve acetabular cup (Wright Medical
Technology (WMT), Arlington, Tennessee).
Materials and Methods:
102
large diameter MoM Conserve cups were
implanted into 92 consecutive patients in the period November 2005 to April
2010. 60
patients (67 hips) and 32 patients (35 hips) were operated at Thisted
Hospital and Viborg Hospital, respectively. The primary choice of femoral
implant was the Profemur stem at Thisted Hospital and the ANCA-Fit stem at
Viborg Hospital (WMT). Mean age at time of surgery was 51.3 years (sd, 12;
range, 14-73) and mean followup period was 51 months (sd, 11.7; range, 14-
73).
All patients were seen by a surgeon in the beginning of 2012. Blood levels
of chrome and cobalt are measured.
Findings / Results:
13
hips (12,7%, SE 3.3) had been revised. Leaving an
overall survival rate of 87.3% after a mean followup of 51 months . The main
reason for revision was aseptic loosening of the acetabular cup. The median
level of chrome and cobalt was 51.3 nM (IQR, 30.3-75.4) and 51.2 nM (IQR,
32.1-125.5),
respectively. No pseudotumores were found.
Conclusions:
The survival rate of the Conserve acetabular cup in this study is
unacceptable low. Continued use cannot be recommended before further
controlled prospective trails have been conducted and shown an acceptable
survival rate without adverse reactions.