AbstractsMedical & Health Science

Metal-on-metal hip arthroplasty: indications for continued use in light of adverse reaction to metal debris

by Gulraj Singh Matharu




Institution: University of Birmingham
Department: School of Health and Population Sciences
Year: 2015
Keywords: R Medicine (General); RD Surgery
Record ID: 1390844
Full text PDF: http://etheses.bham.ac.uk/5836/


Abstract

Adverse reaction to metal debris (ARMD) represents a recently recognised mode of failure of metal-on-metal (MoM) hip resurfacings (HRs) and total hip replacements (THRs). ARMD often requires revision surgery which can have poor outcomes, therefore questioning the future role of MoM hip bearings. The 14-year survival of 447 HRs implanted by a designing surgeon was 94.1% (95% CI 84.9%-97.3%) with the best outcomes in males with primary osteoarthritis. The 8-year survival of 578 MoM THRs was 88.9% (95% CI 78.5%-93.4%) with 44% (17 of 39) of revisions performed for ARMD. A systematic review identified six studies reporting short-term outcomes following 216 ARMD revisions with variable complication (4%-68%) and re-revision (3%-38%) rates. Analysis of outcomes following 64 ARMD revisions demonstrated comparable complication (20.3%) and re-revision (12.5%) rates at a mean 4.5 year follow-up. The 5-year survival following ARMD revision was 87.9% (95% CI 78.9%-98.0%) with revision to another MoM bearing having significantly higher re-revision rates (p=0.046). Male patients with primary osteoarthritis may undergo HR in the future, however designing surgeons may also consider females for HR. There is no future role for MoM THR. Limited evidence exists regarding outcomes following ARMD revision, though exchange to a non-MoM bearing surface is advised.