The Diagnostic Accuracy of the Lever Sign for Detecting Anterior Cruciate Ligament Injury

Abstract

Background: An alternative physical examination procedure for evaluating the integrity of the anterior cruciate ligament (ACL) has been proposed in the literature but has not been validated in a broad population of patients with a symptomatic complaint of knee pain for its diagnostic value.Purpose: To investigate the diagnostic accuracy of the Lever Sign to detect ACL tears and compare the results to Lachman testing in both supine and prone positions.Study design: Prospective, blinded, diagnostic accuracy study.Methods: Sixty-two consecutive patients with a complaint of knee pain were independently evaluated for the status of the ACL's integrity with the Lever Sign and the Lachman test in a prone and supine by a blinded examiner before any other diagnostic assessments were completed.Results: Twenty-four of the 60 patients included in the analysis had a torn ACL resulting in a prevalence of 40%. The sensitivity of the Lever Sign, prone, and supine Lachman tests were 38, 83, and 67 % respectively and the specificity was 72, 89, and 97% resulting in positive likelihood ratios of 1.4, 7.5, and 24 and negative likelihood ratios of 0.86, 0.19, and 0.34 respectively. The positive predictive values were 47, 83, and 94% and the negative predictive values were 63, 89, and 81% respectively. The diagnostic odds ratios were 1.6, 40, and 70 with a number needed to diagnose of 10.3, 1.4, and 1.6 respectively. Conclusions:The results of this study suggest that Lever Sign, in isolation, does not accurately detect the status of the ACL. During the clinical examination, the Lever Sign should be used as an adjunct to the gold standard assessment technique of anterior tibial translation assessment as employed in the Lachman tests in either prone or supine position. Level of Evidence: 2

Comparing the Diagnostic Accuracy of Two Selective Tissue Tests for Anterior Cruciate Ligament Injuries: A Critically Appraised Topic

“…In comparison, the Lachman test had values of 65% and 100%, respectively. 11 Jarbo et al found the sensitivity and specificity for the lever sign test to be 63% and 90%, respectively. 3 They found the values for the Lachman test to be 90% and 96%.…”

“…3,11,12 The included studies compared the sensitivity and specificity values for the lever sign test and the Lachman test. 3,11,12 One study 11 included cohorts of patients under anesthesia when the tests were administered, and the others had cohorts of awake patients. 3,12 Jarbo et al compared results of the tests to the reference standard of MRI.…”

“…3 Mulligan et al compared tests to either MRI or the gold standard, arthroscopic visualization. 11 Lichtenburg et al compared tests to arthroscopic visualization. 12 Mulligan et al found the sensitivity and specificity values for the lever sign to be 33% and 50%, respectively.…”

“…3 In both studies, the Lachman test had better sensitivity and specificity values compared to the lever sign test. 3,11 Lichtenburg et al found the sensitivity and specificity for the lever sign test to be 39% and 100%, respectively. 12 They found the values for the Lachman test to be 87% and 91%, respectively.…”

“…While Lichtenburg et al also found that the sensitivity of the lever sign test was significantly lower than the Lachman test, it contradicts the other two studies by showing the specificity of the lever sign to be better than the Lachman test. 3,11,12 Results of Evidence Quality Assessment…”