Background: Anterior cruciate ligament (ACL) tear is a common knee injury with various manual tests used for clinical diagnosis. The aim of this prospective study was to evaluate the lever sign test sensitivity as a new clinical test for diagnosis of ACL disruptions compared to other manual diagnostic tests. Methods: One hundred patients with chronic ACL tears were included in this study between January 2017 and March 2018. The mean age was 29.1 ±8.2 yr. Four clinical tests (anterior drawer, Lachman test, pivot shift, and lever sign) were obtained in all patients by two different clinicians. The contralateral uninjured knees were used as controls for comparison. The sensitivity of these tests was estimated with recording of the interobserver reliability for lever sign test. Statistically significant differences between the lever test and other clinical tests were assessed using chi-square analysis. Results: The recorded sensitivities of anterior drawer, pivot-shift, and Lachman tests were 82%, 88%, and 91%, respectively. The sensitivity of the lever sign test was much lower (34%) with 100% interrater reliability. There was a statistically significant difference between the lever sign test and other physical tests (P-value <0.05). Conclusions: The lever sign test has much lower sensitivity than other clinical diagnostic tests in patients with chronic ACL lesions. More biomechanical studies should be carried out to prove the validity of this test for the diagnosis of ACL injuries. Level of evidence: Level III.