Outcome in patients lost to follow-up

Long-term outcome studies are valuable for providing information on the results of joint arthroplasty. However, a progressively increasing rate of attrition correlates with the length of study. The attrition rate of patients "lost to follow-up" ("non-attenders") may have a significant effect on the reported outcome. The goal of this study was to analyze the effect of the outcome in patients lost to follow-up on analysis in the setting of total knee arthroplasty. We found a lower rate of failure for revision surgery and higher satisfactory results in "non-attenders" compared with patients completing follow-up. No statistical effect of loss to follow-up care was noted on survivorship analysis when revision surgery or revision plus severe pain were considered as end points. Therefore, the patients who do not attend follow-up visits do not necessarily have poor results.