Update on unicompartmental knee arthroplasty: Current indications and failure modes.

Despite the excellent success rates of modern implants, unicompartmental knee arthroplasty (UKA) continues to show relatively high failure and revision rates, especially when compared with total knee arthroplasty (TKA).These higher rates of failure and revision are mainly observed during the early (< 5 years) post-operative period and are often due to incorrect indications and/or surgical errors.The correct clinical and radiological indications for UKA have therefore been analysed and correlated as far as possible with the principal mechanisms and timing of failures of UKA. Cite this article: 2018;3:442-448. DOI: 10.1302/2058-5241.3.170060.