The knee exam follows the same sequence as the shoulder exam: look, feel, move, then special tests. Always examine the hip too, because hip problems can refer pain to the knee. The knee exam appears on the NPTE, PANCE and USMLE.
Drill the tests with the free knee exam quiz.
Key takeaways
- Lachman is the most sensitive test for an ACL tear.
- Posterior drawer and sag sign: PCL. Valgus: MCL. Varus: LCL.
- McMurray, Thessaly and joint line tenderness: meniscus.
- The Ottawa knee rules decide who needs an X-ray after injury.
USA Knee Exam: Quick Facts
- Sequence
- Inspect → palpate → ROM → special tests
- Normal flexion
- ~135°
- ACL test
- Lachman (most sensitive)
- Also check
- Hip and neurovascular status
Knee Special Tests
| Test | Suggests |
|---|---|
| Lachman / anterior drawer | ACL tear |
| Posterior drawer / sag sign | PCL tear |
| Valgus stress (at 0° and 30°) | MCL injury |
| Varus stress | LCL injury |
| McMurray / Thessaly / joint line tenderness | Meniscal tear |
| Patellar apprehension | Patellar instability |
| Bulge / ballottement | Effusion |
Ottawa Knee Rules
After acute knee injury, an X-ray is indicated if any of these are present:
- Age 55 or older
- Isolated tenderness of the patella
- Tenderness at the head of the fibula
- Inability to flex the knee to 90°
- Inability to bear weight for 4 steps, both right after the injury and in the emergency department
Free practice test
Ready to test yourself?
Choose your test length, practice with instant feedback or take it exam-style, and get your score with an explanation for every answer.
Go to the USA Knee Exam practice test →USA Knee Exam FAQs
Which test is best for an ACL tear?
The Lachman test is the most sensitive clinical test; the pivot shift is highly specific.
Full answer →How do you test for a meniscus tear?
Joint line tenderness, McMurray and Thessaly tests; MRI confirms.
Full answer →When do you need an X-ray for a knee injury?
Use the Ottawa knee rules: age 55+, isolated patellar or fibular head tenderness, inability to flex to 90°, or inability to bear weight for 4 steps.
Full answer →Official sources
Disclaimer: This guide is for general information and is not medical advice. Coverage, prices and requirements change and vary by provider and location. Confirm details with your provider, insurer or the agency listed in the sources. Read our editorial policy.