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Low back and pelvis 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 Low back & pelvis 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 out sacroiliac joint pain?

  1. Gaenslen's test
  2. Distraction test
  3. Thigh thrust (P4) test
  4. Compression test
Show the answer

Answer: C. Thigh thrust (P4) test. Thigh thrust (P4) test has the lowest LR−, 0.18. The others: Compression test 0.46, Distraction test 0.49, Gaenslen's test 0.66. See the test

Question 2 of 8

How far does a positive straight leg raise move the probability of disc herniation with nerve root compression?

  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). Straight leg raise (SLR): LR+ 1.2. Its page: “barely informative: a positive result changes little.” See the test

Question 3 of 8

How far does a positive distraction test move the probability of sacroiliac joint pain?

  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). Distraction test: LR+ 3.2. 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 negative straight leg raise move the probability of disc herniation with nerve root compression?

  1. Down clearly: it is doing real work (LR− below about 0.2)
  2. Down a little: a small shift (LR− between about 0.2 and 0.5)
  3. Barely: it is barely worth the time (LR− above about 0.5)
  4. Up: a negative result makes it more likely
Show the answer

Answer: B. Down a little: a small shift (LR− between about 0.2 and 0.5). Straight leg raise (SLR): LR− 0.35. Its page: “a small shift: a negative result nudges the diagnosis down, but does not exclude it.” See the test

Question 5 of 8

What counts as a positive straight leg raise?

  1. Pain provoked by the pressure with the feet on the floor that eases when the feet are lifted.
  2. Reproduction of the patient's anterior or lateral thigh symptoms; quadriceps stretch alone does not count.
  3. Reproduction of the patient's leg symptoms, usually between about 30° and 70°. Back pain alone does not count.
  4. Reproduction of familiar local or referred pain on the loaded side.
Show the answer

Answer: C. Reproduction of the patient's leg symptoms, usually between about 30° and 70°. Back pain alone does not count. The Straight leg raise (SLR) page: “Reproduction of the patient's leg symptoms, usually between about 30° and 70°. Back pain alone does not count.” See the test

Question 6 of 8

What counts as a positive Hoover test?

  1. Pain provoked by the pressure with the feet on the floor that eases when the feet are lifted.
  2. Reproduction of the patient's anterior or lateral thigh symptoms; quadriceps stretch alone does not count.
  3. Reproduction of the patient's familiar buttock or posterior pelvic pain.
  4. Hip extension on the weak side is weak when tested directly, but the weak heel presses down firmly when the patient lifts the strong leg.
Show the answer

Answer: D. Hip extension on the weak side is weak when tested directly, but the weak heel presses down firmly when the patient lifts the strong leg. The Hoover test page: “Hip extension on the weak side is weak when tested directly, but the weak heel presses down firmly when the patient lifts the strong leg.” See the test

Question 7 of 8

Starting at 30% for sacroiliac joint pain, what is the probability after a positive thigh thrust test?

  1. 36%
  2. 55%
  3. 77%
  4. 7%
Show the answer

Answer: B. 55%. From the ladder on the Thigh thrust (P4) test page: a starting 30% becomes 55% after a positive (LR+ 2.8: a small shift). See the test

Question 8 of 8

Starting at 30% for sacroiliac joint pain, what is the probability after a positive sacral thrust test?

  1. 79%
  2. 52%
  3. 34%
  4. 18%
Show the answer

Answer: B. 52%. From the ladder on the Sacral thrust test page: a starting 30% becomes 52% after a positive (LR+ 2.5: a small shift). See the test

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

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