ARE TRUNNIONS IN HIP HEMIARTHROPLASTIES EXEMPT FROM HIGH WEAR

A modular hemiarthroplasty has a Metal-on-Metal (MoM) taper-trunnion junction, which may lead to increased wear and Adverse-Reaction-to-Metal-Debris (ARMD). To-date no wear related issues have been described in the elderly and less active that receives a hemiarthroplasty. This study aims to determine in vivo wear (i.e. serum metal ion levels) in hip hemiarthroplasty, and identify factors associated with increased wear.This is a prospective, IRB approved, single-centre, cohort study of patients that received an uncemented, modular hemiarthroplasty of proven design for the treatment of hip fracture between 2013–2015. All, alive, patients at 12-months post-implantation with AMTS≥6 were invited to participate. Of the 125 eligible patients, 50 accepted the invitation and were reviewed, including clinical/radiological assessment, metal-ion ([Chromium (Cr) and Cobalt (Co)]) measurement and Oxford Hip Score (OHS). Acetabular erosion was graded (0–3: normal-protrusio). Metal ion levels were considered high if ≥7pp...