2005 – Developed by Alessandro Lelli to better assess the functional aspects of ACL disruption
2014 – Lelli et al reviewed 400 patients divided into four groups (A-D) each with 100 patients. A single clinician, blinded to MRI results, and examined every patient with the same series of physical tests: the Lachman test, Anterior Drawer test, Pivot Shift test, and Lever Sign test.
Few other reviews were done later and they concluded that
* The lever sign test was found to be 95% accurate, 100% sensitive, 94% specific for ACL rupture.
* Anterior drawer/Lachman testing was 88% accurate, 40% sensitive, 100% specific.
* Lever test is the best for Acute ACL examination ( infileld or ED room )
" We have finally found one simple test for ACL injury examination ! "
That was shocking and the question was " is lever test better substitute for Lachmans test ?! "
So many other reviews were done , one of them was the prospective cohort study done in french ski resorts between December 2019 and march 2020 including 285 patient .
The MRIs found 219 ACL tears and 36 intact ACLs. Three MRIs were deemed uninterpretable. The sensitivity of the lever sign test was 61.2% and the PPV was 83.8%. The sensitivity of the Lachman test was 99.1% and the PPV was 86.5%.
They concluded that the sensitivity was lower than expected calculated at 61.2%, was lower than the expected 80% . The Lachman test, on the other hand, showed a very high sensitivity of 99.1%. It remains the test of choice for the clinical diagnosis of ACL tears in patients with knee injuries. Therefore, the lever sign test can complement the Lachman test but is not a substitute for it.
Another study done in Al-Azhar University Cairo including 100 patients in the age of 18-45 confirmed as having ACL injury by MRI. The 4 tests of ACL injury ( anterior drawer - Lachman - pivot shift - lever test ) were done preanesthetic and post anaesthetic and results were compared to Arthroscopic examination.
They found preanesthetia and post anaesthetia sensitivities were 88% and 96% respectively for Lachmans test, 78% and 88%, respectively, for the
anterior drawer test; 54% and 98%,
respectively, for the pivot shift test; and 72% and 80%, respectively, for the levers ign test. The specificity was highest for the pivot-shift test 100%, followed by the Lachman test 96%, anterior drawer test 92%, and lever sign test 92%.
And concluded that lever test could be used in both Acute and chronic injuries as complement test and not substitute for Lachmans and other ACL examination tests. The lever test does not assess the rotational component, which may lead to a missed diagnosis in a partial tear specially we can't eliminate the effect of muscle tension of quadriceps which could mislead results of chronic partial ACL tears .
Additionally, the test is not affected by anesthesia, which cannot be stated for other ACL examinations as pivot shift test.
If we would make a benefit of such reviews , I would say that Lever test could be useful in examination of high BMI patient where high thigh circumstances make it difficult to perform Lachmans test adequately.
Lever test is carried out with patient in supine position, knee in full extension and heel touching the bed.
A clenched fist is placed beneath the proximal calf just distal to tibial tuberosity.
Gentle downwards pressure is applied over quadriceps tendon and the examiner looks to see if the heel ‘lifts off’ the bed.
Negative Lever Sign test. With the fist acting as a fulcrum under the calf and a second hand pushing down on the quadriceps (large arrow), the ACL is able to counteract the downward force on the foot due to gravity (small arrow).
The test is POSITIVE if there is no heel lift-off and indicates likely ACL disruption
With a partially or completely ruptured ACL, the ability to offset the force of gravity on the lower leg is compromised and then tibial plateau slides anteriorly with respect to the femoral condyles. In this case, the gravity pulls the heel down to the examination table
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