Root pain begins in the low back, and shoots down the leg in a narrow band like electricity. In most cases, root pain is the result of inflammation of a nerve root. Steroids reduce inflammation. Since the nerve roots are in the epidural space, epidural steroid injection can therefore reduce root pain by reducing inflammation. The problem is that epidural steroid injections last for about 100 hours, while root pain last more than 12 weeks in half the cases. Common sense has confirmed a number of studies which show epidural injection is not a good treatment for root pain. However, 100 hours of relief is better than nothing at all, and even temporary relief of the pain confirms it is really coming from the nerve root, and not some other source. At Phoenix Spine & Joint, we use epidural injection as a test to confirm the cause of your pain. And we hope you have a great 100 hours, as well.