joint replacement registry joint replacement registry a joint replacement registry is a system of collecting information of arthroplasty outcomes at a population (often national) level, in order to provide an evidence-base for safe and effective treatment options. background the uk registry, the njr, was set up as recommendation of a royal college of surgeons of england review into the high-profile failure of the 3m capital hip. information collected registers collect information on a combination of hip replacements, knee replacements (both total and unicompartmental), shoulder replacements, ankle replacements and elbow replacements. some countries exclude hemiarthroplasties done for traumatic hip fractures. initially designed only to record surgeon and implant performance, the main outcome collected was implant failure, however recently patient-reported outcome measures are being added. research given the amount of information stored, the data from many of the registries is used as the basis of scientific papers, for example on the metal-on-metal hip controversy. worldwide registries there are currently 31 national members of the international society of arthroplasty registers (isar). in addition, in the united states, there are 10 regional or private registries collecting data. country type year started name uk national 2003 njr scotland national sap ireland national 2014 inor italy national ripo portugal national 2009 rpa romania national 2001 rne germany national eprd egypt national 2007 ecar australia national 1999 aoanjrr japan national 2002 jar sweden national 1975 skar sweden national 1979 shar canada national 2003 cjrr the netherlands national 2007 lroi slovakia national 1926 sar new zealand national 1999 nzjr denmark national 1997 dhr norway national 1994 nar finland national 1980 iran national 2016 ijr united states national 2012 ajrr regional cjrr private 2001 kptjrr