Piriformis Syndrome and Tests

Courtesy: Prof Nabil Ebraheim, University of Toledo, Ohio, USA

Piriformis syndrome is a condition presenting as leg pain or sciatica caused by problem related to piriformis muscle.The piriformis muscle arises from the anterolateral part of sacrum and gets inserted to the posterior part of greater trochanter .

It is difficult to differentiate between Piriformis syndrome and lumbar spinal disc herniation as both conditions produce sciatica and are commonly misdiagnosed. The gold standard test to diagnose disc herniation is straight leg raising test . Elevation of affected limb causes sciatica and radicular pain. A positive test indicates spine pathology.

The patient with Piriformis syndrome may present with complaints of deep pain in buttock and posterior thigh. Pain may also radiate to posterior aspect of leg due to irritation of sciatic nerve.

Diagnostic tests include-

1)Laseguer’s maneuver (stretching of the nerve) – the pain is reproduced on flexing the hip to 90 degree and extending knee.

2)FAIR test (stretching of the muscle BY Flexion, Adduction and Internal Rotation)- In this test we assess if the stretching of muscle causes pressure on the nerve thereby causing symptoms.This is done by flexing, adducting and internally rotating the hip. The test is considered positive if stretching of muscle produces pain.