Accuracy of the Lever Sign Test in the Diagnosis of Anterior Cruciate Ligament Injuries

Abstract

Background:The lever sign test is a new physical examination tool to diagnose anterior cruciate ligament (ACL) tears. Preliminary results suggest almost 100% sensitivity and specificity to diagnose acute and chronic complete ACL tears and clinically significant partial tears as compared with magnetic resonance imaging (MRI).Purpose:To assess the sensitivity and specificity of the lever sign test for the diagnosis of acute ACL injuries, as compared to MRI. We also aimed to determine the accuracy of the lever sign test compared with 3 other tests (anterior drawer, Lachman, and pivot shift) when performed by providers of various training levels, and with the patient awake or under anesthesia.Study Design:Cohort study (diagnosis); Level of evidence, 2.Methods:We evaluated patients with a chief concern of acute (≤4 weeks) knee pain seen between October 2014 and January 2015, with a thorough history, physical examination, and standard radiographs. MRI was the reference standard; patients without an MRI evaluation were excluded. The 4 physical examination maneuvers were performed on each symptomatic knee during the initial clinic visit (for nonsurgical patients) or under anesthesia in the operating room (for surgical patients) by a randomly assigned undergraduate student, medical student, orthopaedic resident, or orthopaedic fellow. The senior author trained all staff to perform the lever sign test. Statistical analyses were performed.Results:Of 102 patients, 54 were surgical (28 female, 26 male), and 48 were nonsurgical (16 female, 32 male); the mean patient age was 23 years (range, 15-66 years). The overall accuracy of the lever sign test was 77% (63% sensitivity, 90% specificity); the accuracy was similar between patients under anesthesia and awake (77% vs 76%, respectively). There were no significant differences when comparing the sensitivity and specificity of the lever sign test with patients under anesthesia and awake (sensitivity: under anesthesia, 86%, and awake, 68% [P = .40]; specificity: under anesthesia, 85%, and awake, 96% [P = .17]). Furthermore, the accuracy of the lever sign test was similar when performed on female versus male patients (75% vs 79%, respectively) or when performed by undergraduate students and medical students compared with orthopaedic residents and fellows (84% vs 88%, respectively).Conclusion:Our study results challenge the exceptional sensitivity and specificity values (both 100%) of the lever sign test, as reported by the original author of the test.

Comparison of Diagnostic Accuracy of Physical Examination and MRI in the Most Common Knee Injuries

“…Massey et al [36] estimated the sensitivity of the test to be 83%, and the authors suggest that such a high diagnostic value reported in the original paper might have been caused by the methodology of the study in which the author verified his test on patients with known ACL deficiency, which could have affected the final result. Furthermore, in a study published by Jarbo et al [37], high sensitivity was again not confirmed. What is worth noting is the fact that this examination, contrary to others tested in the study, was independent of patient relaxation, and therefore it might be utilized in daily practice in an acute setting.…”

Reliability and Validity of an Innovative Device for ACL Testing: The Mobil-Aider™

“…10,11 Individual modifications of the tests with varying degrees of tibial rotation and the magnitude of examiner experience have been reported to influence test accuracy. 12,13 The Lachman test is performed in the supine position with the knee in ∼20°of flexion. Whether the test results are interpreted as dichotomous (positive = torn and negative = intact) or graded (grades I, II, and II), there is a subjective element to the data.…”

“…Whether the test results are interpreted as dichotomous (positive = torn and negative = intact) or graded (grades I, II, and II), there is a subjective element to the data. 13,14 The clinician relies on the subjective assessment of end feel and being able to determine millimeters of translation to assign a grade of I (<5 mm), II (5-10 mm), or III (>10 mm). 14 A study by Makhmalbaf et al 5 reported the sensitivity of the Lachman test to be 93.5% with a significant difference between men and women (66.7% vs 94.6%).…”

“…Having an instrument to quantify the linear translation of this ligament would be very valuable. 13,14 Magnetic resonance imaging (MRI) is often used for ACL injury diagnosis. 3 However, an MRI is a static image and is best used in conjunction with instrumented laxity devices to assess biomechanical behavior.…”

Can Preoperative Magnetic Resonance Imaging Predict Intraoperative Autograft Size for Anterior Cruciate Ligament Reconstruction? A Systematic Review

“…22 Thus, much interest has focused on the value of utilizing the magnetic resonance imaging (MRI) to preoperatively measure and glean information on autograft size, given the strong recommendation for its use as part of the overall diagnostic evaluation of patients with suspected ACL injury. 13 In fact, with regard to detecting ACL injury, MRI boasts a 97% sensitivity, 100% specificity, 100% positive predictive value, 96% negative predictive value, and 98% accuracy, 23,24 and additionally, has been instrumental in identifying associated meniscal, articular cartilage, subchondral bone bruise, and collateral ligament pathology. 14,25 However, its value in preoperatively predicting commonly used autograft sizes remains unknown.…”