['The main objective of this study was to analyse the outcomes after total knee arthroplasty (TKA) of a group of patients with at least one self-reported allergy and a group of patients without reported allergies. We hypothesized there is a significant negative influence on clinical outcome scores after TKA in patients with self-reported allergies.', "Four-hundred and seventy-five patients who had undergone TKA were analysed preoperatively and 1\xa0year after surgery. The WOMAC, KSS and SF-36 scores were obtained. The patients' Yesavage depression questionnaire score was also recorded. The scores of the 330 (69.5\xa0%) patients without self-reported allergies were compared to the scores of the 145 (30.5\xa0%) patients with at least one self-reported allergy in the medical record.", 'Preoperative scores were similar in both groups. The WOMAC post-operative scores (23.6 vs 20.4; p\xa0=\xa00.037) and the KSS-Knee score (91.1 vs 87.6; p\xa0=\xa00.027) were worse in the group of patients with self-reported allergies than in the group without allergies. The scores from the Yesavage depression questionnaire and in the SF-36 were similar in both groups.'] Do patient-reported allergies cause inferior outcomes after total knee arthroplasty?