Outcome of revision arthroplasty for failed metal-on-metal total hip replacements; is there a relation with metal ions?

Purpose: We aimed to assess the early outcome following revision arthroplasty for failed metal-on-metal (MoM) total hip replacements (THR) due to adverse reaction to metal debris (ARMD). Methods: We reviewed 106 consecutive revision arthroplasties. Case notes and radiological investigations were reviewed to assess the complications. Oxford Hip Score (OHS) and Euroqol (EQ-5D-3L) scores were used to assess the functional outcome and improvement of quality of life. Results: At a mean follow-up of 20 months (12-48 months), the mean OHS was 28.7. Pain improved in 61% patients. A majority of patients were in level 2 for all the EQ-5D-3L dimensions. The overall complication rate was 16%. Survivorship free from further revision for any cause was 94.3% at 48 months. There was no correlation between pre-revision blood metal ions and the final outcome. Conclusions: Revision surgery for failed MoM hip replacement due to ARMD is associated with a relatively higher rate of complications and risk of chronic pain. There is poor correlation between serum metal ions and development of ARMD and outcome following revision surgery.