Is there some way to find out for sure what’s causing my left buttock pain? I’d like to know the source of my problems before taking steps to treat it.

Pain in the buttocks region can be difficult to sort out. Sometimes it’s coming from muscle, nerve, or other soft tissue structures in the buttocks. In other cases, it’s referred pain meaning the problem is up higher in the back. Often there is a bulging or herniated disc pressing on a nerve causing buttock and/or leg pain.

The piriformis muscle in the buttocks can cause buttock or leg pain called sciatica. A good way to find out if this is the problem is called the FAIR test. FAIR stands for Flexion, Adduction, and Internal Rotation. This is the position the leg is put in to test for piriformis syndrome.

Sometimes a nerve conduction velocity (NCV) test is done. This is a measure of how fast signals travel along the nerve. Any slowing of nerve function helps the examiner find the section of nerve that is involved.

However, NCV tests are invasive and painful. A new test called magnetic stimulation may be a good alternative. A recent study showed it is noninvasive and just as accurate as NCV tests.