Evans JT, et al. - Since the question of how long does a knee replacement last is frequently asked by patients, researchers intended to answer this question in this systematic review and meta-analysis of case series and national registry reports with more than 15 years of follow-up via searching MEDLINE and Embase for case series and cohort studies published from database inception until July 21, 2018. A more optimistic estimate than pooled registry data appears to be shown by pooled survival derived from case series. According to findings, approximately 82% of total knee replacements (TKRs) last 25 years and 70% of unicondylar knee replacements (UKRs) last 25 years. Patients and healthcare providers will benefit from these findings.