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Knee special tests quiz

Questions use only the figures on this library's test pages.

Last updated 30 October 2026. 8 questions. Each answer links to the test page it comes from; the region's tests are listed on the Knee cheat sheet.

Terms such as sensitivity, specificity, LR+ and LR− are explained in the glossary. A likelihood ratio above about 5 or below about 0.2 is doing real work; between 2 and 0.5 it is barely worth the time.

Question 1 of 8

Which of these tests best rules in ACL rupture?

  1. Anterior drawer test
  2. Lachman test
  3. Lever sign (Lelli test)
  4. Pivot shift test
Show the answer

Answer: D. Pivot shift test. Pivot shift test has the highest LR+, 10.7. The others: Anterior drawer test 6.34, Lachman test 5.72, Lever sign (Lelli test) 3.15. See the test

Question 2 of 8

How far does a positive popliteal fossa examination move the probability of Baker's (popliteal) cyst?

  1. Up clearly: it is doing real work (LR+ above about 5)
  2. Up a little: a small shift (LR+ between about 2 and 5)
  3. Barely: it is barely worth the time (LR+ below about 2)
  4. Down: a positive result makes it less likely
Show the answer

Answer: A. Up clearly: it is doing real work (LR+ above about 5). Popliteal fossa examination for a cyst (palpable mass / Foucher's sign): LR+ 6.3. Its page: “a moderate rule-in: a positive result makes the diagnosis clearly more likely.” See the test

Question 3 of 8

How far does a positive McMurray's test move the probability of meniscal tear?

  1. Up clearly: it is doing real work (LR+ above about 5)
  2. Up a little: a small shift (LR+ between about 2 and 5)
  3. Barely: it is barely worth the time (LR+ below about 2)
  4. Down: a positive result makes it less likely
Show the answer

Answer: B. Up a little: a small shift (LR+ between about 2 and 5). McMurray's test: LR+ 2.4. Its page: “a small shift: a positive result nudges the diagnosis up, but does not settle it.” See the test

Question 4 of 8

How far does a positive result on the knee osteoarthritis clinical criteria (ACR decision tree) move the probability of knee osteoarthritis?

  1. Up clearly: it is doing real work (LR+ above about 5)
  2. Up a little: a small shift (LR+ between about 2 and 5)
  3. Barely: it is barely worth the time (LR+ below about 2)
  4. Down: a positive result makes it less likely
Show the answer

Answer: C. Barely: it is barely worth the time (LR+ below about 2). Knee osteoarthritis clinical criteria (ACR decision-tree format): LR+ 1.6. Its page: “barely informative: a positive result changes little.” See the test

Question 5 of 8

What counts as a positive Lachman test?

  1. Pain or clicking with compression and rotation that eases with distraction.
  2. A palpable or audible click or thud at the joint line, with or without the patient's pain.
  3. A clunk as the subluxed lateral tibial plateau reduces, at around 20–40° of flexion.
  4. Greater anterior translation than in the other knee, with a soft or absent end-feel.
Show the answer

Answer: D. Greater anterior translation than in the other knee, with a soft or absent end-feel. The Lachman test page: “Greater anterior translation than in the other knee, with a soft or absent end-feel.” See the test

Question 6 of 8

What counts as a positive joint line tenderness test?

  1. Tenderness at the joint line itself, not over the collateral ligament above or below it.
  2. A clunk as the subluxed lateral tibial plateau reduces, at around 20–40° of flexion.
  3. Pain or clicking with compression and rotation that eases with distraction.
  4. A palpable or audible click or thud at the joint line, with or without the patient's pain.
Show the answer

Answer: A. Tenderness at the joint line itself, not over the collateral ligament above or below it. The Joint line tenderness page: “Tenderness at the joint line itself, not over the collateral ligament above or below it.” See the test

Question 7 of 8

Starting at 30% for ACL rupture, what is the probability after a positive anterior drawer test?

  1. 8%
  2. 82%
  3. 57%
  4. 73%
Show the answer

Answer: D. 73%. From the ladder on the Anterior drawer test page: a starting 30% becomes 73% after a positive (LR+ 6.34: a moderate rule-in). See the test

Question 8 of 8

Starting at 30% for meniscal tear, what is the probability after positive joint line tenderness?

  1. 51%
  2. 73%
  3. 12%
  4. 59%
Show the answer

Answer: D. 59%. From the ladder on the Joint line tenderness page: a starting 30% becomes 59% after a positive (LR+ 3.3: a small shift). See the test

Other quizzes: Shoulder · Neck · Low back & pelvis · Hip, groin & thigh · Foot, ankle & calf · Elbow & forearm · Wrist & hand. How the figures are chosen: Methods.

Get the book for how to do and read each knee test with published figures, and which ones to trust for the ACL, meniscus and kneecap

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