Lever test: Role of its assistance in diagnosis of anterior cruciate ligament injury

Introduction: The diagnosis of Anterior Cruciate Ligament (ACL) tear is aided by clinical tests and imaging evaluation with MRI. The main clinical tests include Lachman, Anterior Drawer and Pivot shift test. A newer clinical test called lever test was proposed recently with higher sensitivity compared to traditional tests. Objective: To investigate the sensitivity, specificity and other statistical parameters of newly proposed lever test for ACL injury in comparison to other established tests, Lachman test, Anterior Drawer test and Pivot Shift test. Materials and Methods: 242 consecutive patients between ages of 18 to 50 years with a complaint of knee pain and giving way after trauma were included in the study over a period of 4. They were evaluated with clinical tests Lever test, Lachman test, Anterior Drawer test and Pivot Shift test without anaesthesia and under anaesthesia. All patients were subjected to diagnostic arthroscopy who’s the results were taken as gold standard and sensitivity, specificity, positive and negative predicative values for all tests were calculated. Results: The pre-anaesthesia and post-anaesthesia sensitivity of Lever test was 85.57% and 91.75 respectively. This was lower than the sensitivity of Lachman test (Pre-anaesthesia: 93.81%, Post-anaesthesia: 98.97) but higher than the other two tests. (Anterior Drawer Test: Pre-anaesthesia: 80.41%, Post-anaesthesia: 93.81%, Pivot Shift Test: Pre-anaesthesia: 40.21% Post-anaesthesia: 75.26%) Conclusion: The sensitivity lever test is higher compared to Anterior Drawer test and Pivot Shift test but lower than the Lachman test. Inclusion of lever test may improve diagnostic accuracy of clinical evaluation of ACL tear.

Keywords

anterior cruciate ligament, diagnosis, knee, lachman test, lever sign, sensitivity, specificity