Execution
- 1Position the patient supine.
- 2First apply valgus stress with the knee in full extension.
- 3Repeat valgus stress with the knee flexed approximately 20 to 30 degrees.
- 4Stabilize the lateral femur and applies an abducting force to the distal tibia.
- 5Compare medial joint opening, pain, and end feel with the opposite knee.
Positive outcome
Medial joint opening, pain, or a soft end feel at 30 degrees is positive for MCL injury. Laxity in full extension suggests more extensive injury involving capsule or cruciate ligaments. Magee grades sprains by pain, opening, and end feel.
Studies
| Study | Reliability | Sn | Sp | LR+ | LR− |
|---|---|---|---|---|---|
| Schafer et al. (2016) | biomechanical study | NA | NA | NA | NA |
| Kastelein et al. (2008) | NA | 86 | 49 | 1.7 | 0.29 |
CommentValgus stress is a core MCL test, but diagnostic accuracy depends on acute pain, swelling, grade of tear, and whether 0-degree and 30-degree positions are tested separately. A clear side-to-side laxity difference is more useful than pain alone. Full-extension laxity should trigger concern for multiligament injury.
Moderate Clinical Value