Lever sign (Lelli test)
For: ACL rupture
Website-only page: no separate test card in the book, which discusses this in its ‘The knee’ chapter.
A tear of the anterior cruciate ligament, which stops the shin sliding forwards and rotating on the thigh bone. Usually from a twisting or pivoting injury.
Treat with caution (see below)Likelihood ratios as published by the review from its pooled statistical model, so they differ from the ratio of the rounded sensitivity and specificity.
Caution: The five meta-analyses cited here disagree, mainly on specificity (LR+ 3.2 to 9.9); a 2025 study with a blinded tester found LR− 0.60–0.93, so a negative lever sign does not rule out an ACL tear.
How it is done
Patient lies on their back with both legs straight and relaxed. The examiner places a closed fist under the upper third of the calf, then presses down on the lower third of the thigh, just above the knee, with the other hand. Negative (ACL intact): the heel lifts off the couch. Positive (ACL torn): the heel stays on the couch.
What the studies found
ACL tear. Figures are the pooled estimates of Hu et al. 2024 (12 studies, 1,365 patients): sensitivity 81.0%, specificity 78.4%. The five meta-analyses cited here disagree, mainly on specificity, and LR+ ranges from 3.2 to 9.9 across them. Hesmerg 2024, the largest (23 studies, 2,516 patients), found sensitivity 79.2% (95% CI 68.7–86.9%) and specificity 92.0% (95% CI 82.2–96.6%) without anaesthesia, which gives LR+ 9.9 and LR− 0.23. Tanaka 2022 (acute injuries only): sensitivity 82%, specificity 88%, LR− 0.21. Reiman 2018: LR+ 9.2 (95% CI 0.70–46.1), LR− 0.58, with only 2 of 8 included studies of high quality. Sokal 2022: sensitivity 83%, specificity 91%, LR− 0.18. A 2025 study (Norris: 101 patients tested at least 3 weeks after the injury, MRI as the reference) found that, for the tester blinded to all other information, LR− was 0.60 to 0.93 depending on the surface the patient lay on (0.45 at best for the unblinded tester), so a negative lever sign does not rule out an ACL tear. Tanaka 2022 describes a positive test as a heel rise, the opposite of the description used here (heel stays down = positive), which follows Hu 2024.
What the numbers mean
- Positive result: a small shift: a positive result nudges the diagnosis up, but does not settle it.
- Negative result: a small shift: a negative result nudges the diagnosis down, but does not exclude it.
The ladder: what a result does to your estimate
| If you thought | After a positive | After a negative |
|---|---|---|
| 10% | 26% | 2% |
| 30% | 57% | 8% |
| 50% | 76% | 17% |
Calculated from the likelihood ratios above. Read the caution above before relying on these. For any other starting estimate, use the probability calculator.
Work out what a result means for your patient: probability calculator
Other tests in the library for ACL rupture
Compare all the tests for ACL rupture side by side
Source
Hu S, Wang X, Wang Q, Feng W. Lever sign test for anterior cruciate ligament injuries: a diagnostic meta-analysis. J Orthop Surg Res. 2024;19(1):155. Journal article (DOI) · meta-analysis
Also cited: Hesmerg MK, Oostenbroek MHW, van der List JP. Lever sign test shows high diagnostic accuracy for anterior cruciate ligament injuries: a systematic review and meta-analysis of 3299 observations. Knee. 2024;47:81–91. Journal article (DOI)
Also cited: Tanaka S, Inoue Y, Masuda Y, Tian H, Jung H, Tanaka R. Diagnostic accuracy of physical examination tests for suspected acute anterior cruciate ligament injury: a systematic review and meta-analysis. Int J Sports Phys Ther. 2022;17(5):742–752. Journal article (DOI)
Also cited: Reiman MP, Reiman CK, Décary S. Accuracy of the lever sign to diagnose anterior cruciate ligament tear: a systematic review with meta-analysis. Int J Sports Phys Ther. 2018;13(5):774–788. PubMed
Also cited: Sokal PA, Norris R, Maddox TW, Oldershaw RA. The diagnostic accuracy of clinical tests for anterior cruciate ligament tears are comparable but the Lachman test has been previously overestimated: a systematic review and meta-analysis. Knee Surg Sports Traumatol Arthrosc. 2022;30(10):3287–3303. Journal article (DOI)
Also cited: Norris R, Price A, Byrne J, Pulford S, van Melick N, Maddox TW, Boswell W, Kerin C, Oldershaw RA. The lever sign test demonstrates limited clinical utility for diagnosing full-thickness anterior cruciate ligament tears after a traumatic knee injury. Orthop J Sports Med. 2025;13(5):23259671251334775. Journal article (DOI)
Website-only page, added to the library on 9 October 2026. Rule It In, Rule It Out discusses this but has no separate test card for it. Figures independently checked against the sources cited above; any note above says where only the abstract could be checked.
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