Background. This study aims to adapt the Tegner Activity Scale (TAS) to Italian language and establish its reliability and validity in patients after anterior cruciate ligament reconstruction. It was hypnotized the Italian version of the TAS have acceptable psychometric properties for use with the Italian population.

Methods. This is an observational multicenter study. The Tegner Activity Scale was translated and culturally adapted according to the Beaton guidelines. A web-based survey was conducted to evaluate the construct validity: 62 patients were included in the study. Spearman’s rank correlation coefficient (r) between the TAS and the Short Form 36 (SF-36) subscales and the International Knee Documentation Committee (IKDC) was used to evaluate construct validity. The patients completed the TAS again one week after their first submission, and the intraclass correlation coefficient was used to calculate the test-retest reliability.

Results. The correlation coefficient showed moderate correlation with the SF-36 Physical Function domain (r = 0.41; p = 0.001) and weak correlation with the IKDC (r = 0.3; p = 0.02). Correlations with the other SF-36 subscales were very weak and not statistically significant. Test-retest reliability (0.68, 95%CI 0.43-0.83) ranged from good to excellent.

Conclusions. The Italian version of the Tegner Activity Scale is a valid instrument to assess a patient’s level of sporting activity after anterior cruciate ligament reconstruction. Cultural adaptation of this scale is fundamental to make this instrument comparable throughout scientific literature.