Execution
- 1Position the patient supine and relaxes the tested knee.
- 2Flex the knee to approximately 20 to 30 degrees.
- 3Stabilize the distal femur with one hand.
- 4Grasp the proximal tibia with the other hand and pull the tibia anteriorly.
- 5Compare anterior translation and end feel with the opposite knee.
Positive outcome
Excessive anterior tibial translation compared with the opposite knee or a soft end feel is positive. The test is graded by translation amount and quality of end point. It is most useful for ACL injury, especially acute complete rupture.
Studies
| Study | Reliability | Sn | Sp | LR+ | LR− |
|---|---|---|---|---|---|
| van Eck et al. (2013) | systematic review/meta-analysis | 81 | 81 | 12.4 | 0.23 |
| Benjaminse et al. (2006) | meta-analysis | 85 | 94 | 10.2 | 0.2 |
CommentLachman is the best-supported manual test for ACL rupture, but estimates vary by acute versus chronic status, complete versus partial tear, and examiner experience. Magee describes multiple modifications, but the core principle is 20 to 30 degrees flexion with anterior tibial translation. Value is high because meta-analyses support strong rule-in performance.
High Clinical Value