Purpose: To assess for the sacroiliac joint or hip joint being the source of the patient's pain.
Test Position: Supine.
Performing the Test: The patient's tested leg is placed in a "figure-4" position, where the knee is flexed and the ankle is placed on the opposite knee. The hip is placed in flexion, abduction, and external rotation (which is where the name FABER comes from). The examiner applies a posteriorly directed force against the medial knee of the bent leg towards the table top. A positive test occurs when groin pain or buttock pain is produced. Due to forces going through the hip joint as well, the patient may experience pain if pathology is located in the hip as well.
Diagnostic Accuracy: Sensitivity: .71, Specificity: 1.0; -LR: .23 ("Pain provocation tests for the assessment of sacroiliac joint dysfunction"), +FABER Test in 97% of patients with labral impingement (phillippon et al, AJSM, 2007).
Importance of Test: When this test is clustered, it can prove highly useful in identifying those suffering from sacroiliac joint dysfunction. Check out the Lumbar Spine/Sacroiliac home page for the cluster. This tests the sacroiliac joint, because as the horizontal abduction force goes through the femur, the tensioned soft tissues transfer the forces to the sacroiliac joint. Hence, this test can indicate pathology located in the hip or sacroiliac joint. The test also assesses the hip, due to forces being transferred through the joint. The position of flexion, abduction, and external rotation, when combined with overpressure, stresses the femoral-acetabular joint and produces pain, if irritated.
Note: tests should only be performed by a properly trained health care practitioner.
References: Broadhurst N, Bond M. "Pain provocation tests for the assessment of sacroiliac joint dysfunction." J Spinal Disorders 1998; 11: 341-345.