# The Lever Sign Test Demonstrates Limited Clinical Utility for Diagnosing Full-Thickness Anterior Cruciate Ligament Tears After a Traumatic Knee Injury

## TL;DR

The lever sign test is not very useful for diagnosing full-thickness ACL tears after knee injuries, as its results depend on factors like the surface used and the examiner's hand position.

## Contribution

This study evaluates the lever sign test's reliability and validity in diagnosing ACL tears, showing its limited clinical utility.

## Key findings

- Interrater reliability was moderate on soft surfaces (κ = 0.529) but not high.
- Test outcomes were influenced by surface type and fist position, but not by effusion grade, force, or pain.
- The lever sign test showed limited clinical utility for diagnosing full-thickness ACL tears.

## Abstract

Current systematic reviews with meta-analyses have identified the lever sign test as the best clinical examination for ruling out an anterior cruciate ligament (ACL) tear, but the included studies have methodological limitations that could bias the test outcome, potentially overestimating its clinical utility.

To investigate the interrater reliability and concurrent validity of the lever sign test after a traumatic knee injury and to investigate the association between test variables (surface used, fist position, effusion grade, force applied, pain reported) and test outcomes.

Cohort study (Diagnosis); Level of evidence, 2.

The lever sign test was performed on hard and soft surfaces in 101 participants after a traumatic knee injury. Magnetic resonance imaging was used as the reference standard, with index testing performed after magnetic resonance imaging was conducted (>3 weeks after injury). Agreement between observers based on the surface used and fist position was evaluated with the Cohen kappa coefficient (κ). Concurrent validity was assessed through sensitivity, specificity, and likelihood ratios. Logistic regression was used to determine whether effusion grade, force applied, and pain reported were significantly associated with test outcomes.

Interrater reliability was superior on the soft surface but demonstrated only moderate agreement (κ = 0.529 [95% CI, 0.368-0.691]). Sensitivity was higher on the soft surface, and specificity was higher on the hard surface, for both assessors. At best, positive and negative likelihood ratios were 3.02 (95% CI, 1.60-5.69) and 0.45 (95% CI, 0.28-0.73), respectively. Test outcomes were affected by the surface used and fist position, but effusion grade, force applied, and pain reported were not significantly associated with correct/incorrect test results.

In participants assessed from 3 weeks after a traumatic knee injury, the lever sign test demonstrated limited clinical utility for diagnosing full-thickness ACL tears. Test outcomes were affected by the surface used and fist position of the assessor.

NCT05416632 (ClinicalTrials.gov)