Posterior Pelvic Pain Provocation Test (PPPP / P4 / Thigh Thrust Test)

The Posterior Pelvic Pain Provocation Test (PPPP), also known as the P4 test, Thigh Thrust test, Posterior Shear test, or POSH test, is a clinical provocation test used to assess sacroiliac joint (SIJ) dysfunction. It is particularly relevant in distinguishing between pelvic girdle pain and lumbar spine pain, often in pregnant women and postpartum patients¹²³.

• 

Test Procedure

Patient position

• The patient lies in supine position with the hip flexed to 90° and the knee bent, which stretches the posterior pelvic structures.

Examiner hand placement

• One hand is placed under the sacrum to stabilize the pelvis.

• The other hand is positioned over the patient’s knee.

Force application

• The examiner applies an axial force along the femur, transmitting pressure posteriorly through the ilium toward the SIJ.

• Some sources suggest adding slight adduction toward the midline to increase sensitivity, though this may increase discomfort⁴⁵⁶⁷.

Interpretation

• Positive test: The patient reports familiar pain localized over the sacroiliac joint.

• Negative test: No pain is reproduced.

Evidence

The gold standard for evaluating SIJ pain is an image-guided intra-articular anesthetic injection. Research has shown that no single SIJ provocation test is sufficient for diagnosis. However, a cluster of tests significantly improves diagnostic accuracy (Grade A recommendation)¹⁰¹¹¹²¹³.

The most validated cluster includes:

• Distraction test

• Compression test

• Thigh Thrust test (P4)

• Gaenslen’s test

• Sacral thrust test

Laslett et al. (2005) concluded that if both the distraction and thigh thrust tests reproduce the patient’s familiar pain, further confirmatory procedures are often unnecessary due to their high combined sensitivity and specificity¹³.

Reliability and Diagnostic Accuracy

Clinical research with moderate-to-high methodological quality shows that the PPPP test demonstrates:

• Intertester reliability: 94.1% (κ = 0.64–0.82, p < 0.001)

• Sensitivity: 80–88%

• Specificity: 100%

• Positive predictive value (PPV): 25–70%

• Negative predictive value (NPV): 88–92%¹⁴¹⁰¹³¹⁵

Clinical Relevance

• The PPPP test is highly reliable and specific for SIJ pain provocation.

• Due to its high sensitivity and specificity, it is frequently used as part of a cluster of SIJ tests.

• Particularly useful in assessing pregnancy-related pelvic girdle pain (PGP), but also applied in non-pregnant populations with suspected sacroiliac dysfunction.

• Should not be used in isolation—must be interpreted alongside patient history, physical examination, and possibly imaging.

Conclusion

The Posterior Pelvic Pain Provocation Test (P4/Thigh Thrust Test) is one of the most validated and reliable provocation tests for sacroiliac joint dysfunction. With high sensitivity, specificity, and intertester reliability, it is especially valuable when used as part of a cluster of SIJ tests. While a positive test strongly indicates SIJ involvement, it should always be considered in the context of other findings and patient history.

References

1. Freburger JK, Riddle DL. Using published evidence to guide the examination of the sacroiliac joint region. Physical therapy. 2001 May 1;81(5):1135-43.

2. Laslett M, Young SB, Aprill CN, McDonald B. Diagnosing painful sacroiliac joints: A validity study of a McKenzie evaluation and sacroiliac provocation tests. Australian Journal of Physiotherapy. 2003 Jan 1;49(2):89-97.

3. Laslett M, Aprill CN, McDonald B, Young SB. Diagnosis of sacroiliac joint pain: validity of individual provocation tests and composites of tests. Manual therapy. 2005 Aug 1;10(3):207-18.

4. P Vercellini. Chronic pelvic pain. Wiley-Blackwell 2011: 118-119

5. Broadhurst NA, Bond MJ. Pain provocation tests for the assessment of sacroiliac joint dysfunction. Journal of spinal disorders. 1998 Aug;11(4):341-5.

6. M Laslett. Pain provocation sacroiliac joint tests: reliability and prevalence. In: Vleeming A, Mooney V, Snijders CJ, Dormann TA, Stoeckart R, editors. Movement, Stability and Low Back Pain: The Essential Role of the Pelvis. 1st ed. New York: Churchill Livingstone; 1997

7. Laslett M, Williams M. The reliability of selected pain provocation tests for sacroiliac joint pathology. Spine. 1994 Jun;19(11):1243-9.

8. Mattptnation. The Thigh Thrust Test. Available from: https://www.youtube.com/watch?v=sJLRimMDR_E [last accessed 25/10/2020]

9. Wchaffe. The Thigh Thrust Test. Available from: https://www.youtube.com/watch?v=Va-2ReIvwJk [last accessed 25/10/2020]

10. Stuber KJ. Sspecificity, sensitivity, and predictive values of clinical tests of the sacroiliac joint: a systematic review of the literature. The Journal of the Canadian Chiropractic Association. 2007 Mar;51(1):30.

11. BA Zelle, GS Gruen, S Brown, S George. Sacroiliac dysfunction: evolution and management. Clin J Pain. 2005; 21(5):446-455

12. JK Freburger, DL Riddle. Using Published Evidence to Guide the Examination of the Sacroiliac Joint Region. Physical Therapy. 2001; 81(5):1135-1143

13. Laslett M, Aprill CN, McDonald B, Young SB. Diagnosis of sacroiliac joint pain: validity of individual provocation tests and composites of tests. Manual therapy. 2005 Aug 1;10(3):207-18.

14. Chen YC, Fredericson M, Smuck M. Sacroiliac joint pain syndrome in active patients: a look behind the pain. The Physician and sportsmedicine. 2002 Nov 1;30(11):30-7.

15. Mousaui SJ, Mousaui L, Alavizadeli A, Kamal S. Jrnl of Research in Rehabilitation Sciences; Vol 3, No.1(86).