Purpose of Test: To test for the presence of a disc herniation.
Test Position: Supine.
Performing the Test: The examiner will passively flex the patient’s uninvolved hip while maintaining the knee in full extension. A positive test is considered when the patient reports reproduction of pain in the involved limb at 40 degrees of hip flexion or less in the uninvolved limb. The examiner should make note of the degree of hip flexion where the patient reported pain or reproduction of symptoms.
Diagnostic Accuracy: Sensitivity: .29, Specificity: .88 ("The test of Lasegue. Systematic review of the accuracy in diagnosing herniated discs").
Importance of Test: Disc herniations are a common problem in patients with low back pain. During this test the examiner is placing a traction force on the uninvolved nerve root, which places tension on the involved nerve root as well, reproducing the pain the patient presented with. Normally, patients can reach 70-90 degrees of hip flexion before a sensation of tightness occurs in the posterior thigh. If pain is felt significantly earlier, the patient could potentially be suffering from a disc herniation. (Interesting fact: The SLR primarily puts a stretch on the L5-S1 nerve root segment due to the nerve segments of the sciatic nerve). It should be noted that a painful, stretching, or other neurological symptom may be produced by this test as a result of neural tension due to adhesions while traveling throughout the body. Compare the results of the test with the pain for which the patient sought treatment. Also, utilize the angle at which symptoms were produced to help differentiate the source of the patient's pain.
Note: tests should only be performed by a properly trained health care practitioner.
References: Deville W, van der Windt D, Dzaferagic A, et al. "The test of Lasegue. Systematic review of the accuracy in diagnosing herniated discs." Spine 200; 25: 1140-1147.