Adverse reaction to metal debris (ARMD) is an increasingly recognised complication of metal-on-metal hip arthroplasty. A previous study described poor results following revision and recommended early intervention1. We determined the outcome of revision for ARMD and present the largest case series to date. Between 2005 and 2010, 98 patients (101 hips) underwent revision for ARMD. The diagnosis of ARMD was based on clinical history, examination, appearance at revision and histology. Patients were reviewed at 3, 6 and 12 months and annually thereafter. Patient satisfaction, Harris hip scores (HHS) and metal ions were analysed.Introduction
Methods
Although safer than ever, allogeneic transfusion is still associated with risks for the recipient (haemolysis, infection, immunosuppression, transfusion-related acute lung injury and even death). Tranexamic acid (TA) is a synthetic antifibrinolytic agent that has been successfully used to stop bleeding after dental operation, removal of tonsils, prostate surgery, heavy menstrual bleeding, eye injuries and in patients with Haemophilia. In this study Tranexamic acid was applied topically to the exposed tissue around the knee joint prior to the wound closure and tourniquet release. It is anticipated that this method of administration is quick, easy, associated with less systemic side effect. Also, it provides a higher concentration of the Tranexamic acid at the bleeding site.
In our independent centre, in the period from January 2003 to august 2008, over 1100 36mm MoM THRs have been implanted as well as 155 Birmingham Hip Resurfacing procedures, 402 ASR resurfacings and 75 THRs using ASR XL heads on SROM stems. During this period we have experienced a number of failures with patients complaining of worsening groin pain at varying lengths of time post operatively. Aspiration of the hip joints yielded a large sterile effusion on each occasion. At revision, there were copious amounts of green grey fluid with varying degrees of necrosis. There were 11 failures of this nature in patients with ASR implants (10 females) and 2 in the 36 MoM THR group (one male one female). Tissue specimens from revision surgery showed varying degrees of ‘ALVAL’ as well as consistently high numbers of histiocytes. Metal debris was also a common finding. A fuller examination of our ASR cohort as a whole has shown that smaller components placed with inclinations >
45° and anteversions <
10 or >
20° are associated with increased metal ion levels. The 11 ASR failed joints were all sub optimally positioned (by the above definition), small components. Explant analysis using a coordinate measuring machine and out of roundness device confirmed greater than expected wear of each component. The lower number of failures in the 36mm MoM group, as well as the equal sex incidence, suggests that the majority of these failures are due to the instigation of an immune reaction by large amounts of wear debris rather than adverse reactions to well functioning joints. It is likely that small malpositioned ASRs function in mixed to boundary lubrication, and this, combined with the larger radius of these joints compared to the 36mm MoM joints, results in more rapid wear.