Purpose: To assess for decreased motion at one of the sacroiliac joints.
Test Position: Sitting.
Performing the Test: The examiner has a hand on each PSIS. The patient bends forward, while the examiner is comparing the movement of each PSIS. A positive test is if greater superior motion is felt on one PSIS compared to the other.
Diagnostic Accuracy: ICC=.25 ("A clinical prediction rule for classifying patients with low back pain who demonstrate short-term improvement with spinal manipulation") Sensitivity: .09; Specificity: .93 ("Four clinical tests of sacroiliac joint dysfunction: the association of test results with innominate torsion among patients with and without back pain").
Importance of Test: It is a debatable topic as to whether there is motion occurring at the SI joint. This test is used to determine if restrictions are present in the sacroiliac joint. As the patient bends forward, the structures that attach to the pelvis rotate the inominates in an anterior direction relative to the starting position. This is why the PSIS's are felt moving superiorly. Should there be a restriction in one of the sacroiliac joints, the PSIS will not feel like it's moving as high as the opposite side. Some argue that this test is more effective in judging sacroiliac restrictions compared to the Standing Forward Flexion Test, because the sacrum is better stabilized by the table. It should be noted that abnormal SI motion can be found in asymptomatic patients, so this test should not be used to triangulate the origin of the patient's symptoms.
Note: tests should only be performed by a properly trained health care practitioner.
References: Flynn T, Fritz J, Whitman J, et al. "A clinical prediction rule for classifying patients with low back pain who demonstrate short-term improvement with spinal manipulation."Spine 2002; 27: 2835-2843.
Levangie PK. "Four clinical tests of sacroiliac joint dysfunction: the association of test results with innominate torsion among patients with and without back pain." Phys Ther. 1999 Nov;79(11):1043-57. Web. 08/19/2012.