The spine is made up of bones called vertebrae. At the front of the spine is solid bone, and at the back there is a bony canal, or channel. The solid bone is separated from the next bone by a disc. One vertebra is connected to the next vertebra at the back in the bony canal by pairs of facet joints on the right and left sides of the spine. These joints allow forward and backward bending, as well as side-to-side rotation. The joints also prevent one vertebra from slipping over the other.
An image guided facet joint corticosteroid injection involves using a live x-ray to guide the injection of a thin needle containing corticosteroid (or ‘steroid’) into one of these facet joints. The injections are designed to decrease inflammation in the facet joint and will often reduce pain.