Reliability and validity of the Lever Sign Test in suspected ligament and/or meniscus injuries of the knee: a comparison between an orthopaedist and a physical therapist

Abstract

The purpose of this study was to investigate the intertester reliability and validity of the Lever Sign Test. Intertester reliability has received little attention in previous studies. In order to make comparisons with other studies, the intertester reliability and validity of the Lachman and Anterior Drawer Tests were also calculated. Patients between 18 and 50 years of age with suspected ligament and/or meniscus injuries were included. Exclusion criteria were suspected malignant, systemic, or central neurologic disease, acute cartilage injury, suspected fracture, or knowledge of the participant's knee findings. Testing was randomized and blinded by an experienced orthopaedic surgeon and a physical therapist. Cohen's kappa was calculated for intertester reliability. Sensitivity and specificity, positive and negative predictive value, and positive and negative likelihood ratio were calculated. MRI findings were used as the gold standard. Thirty-six patients were enrolled in the study, 27 male (75%) and 9 female (25%). The prevalence of anterior cruciate ligament lesions was 44.4%. Cohen's kappa (κ) was κ=0.6 (CI 95% [0.29, 0.91]) for the Lever Sign Test, κ=0.64 (CI 95% [0.35, 0.93]) for the Lachman test, and κ=0.63 (CI 95% [0.3, 0.95]) for the Anterior Drawer Test. The sensitivity of the Lever Sign Test was 0.53 and 0.40 for the orthopaedic surgeon and physical therapist, respectively, specificity was 0.89 and 0.79, the positive predictive value was 0.80 and 0.60, the negative predictive value was 0.70 and 0.62, the positive likelihood ratio was 4.80 and 1.90, respectively, and the negative likelihood ratio was 0.76 and 0.53. The estimated intertester reliability of the Lever Sign Test was good. The Lever Sign Test is suitable as a complement to the Lachman Test, which is considered the most valid test in the literature. The weaknesses and ambiguities of the operating mechanism of the Lever Sign Test should not be ignored and should be further explored.