Lelli Test (Lever Sign Test)

Published July 2, 2026 Read time 2 min read Readers 2
Lelli Test

What is the "Lelli Test (Lever Sign Test)" used for?

  • Integrity of the anterior cruciate ligament (ACL) of the knee.

How to perform the "Lelli Test (Lever Sign Test)"?

The patient is in supine with the knee fully extended on the examining table. 

  • The examiner places a closed fist under the proximal third of the patient’s calf which causes the knee to flex slightly. 
  • The examiner’s other hand then slowly applies a moderate downward force to the distal third of the quadriceps (i.e., the femur) while watching the relation of the tibial plateau to the femoral condyles.

What is the positive result?

Negative (Normal) Test

  • When the ACL is intact, the applied downward force on the femur causes the tibia to act as a lever.
  • As a result, the heel lifts off the examination table.
  • This indicates normal anterior stability of the knee.

Positive Test

  • When the ACL is partially or completely torn, the tibia slides anteriorly relative to the femur.
  • The lever mechanism fails, and the heel does not rise from the table.
  • This finding is considered a positive Lelli Test, suggesting ACL insufficiency.

Test Accuracy

  • Sensitivity: 38%
  • Specificity: 72%

References

  • Mulligan EP, Anderson A, Watson S, Dimeff RJ. The diagnostic accuracy of the lever sign for detecting anterior cruciate ligament injury. Int J Sports Phys Ther. 2017;12(7):1057–1067. PubMed