A dorsal root ganglion (DRG) block is an injection of local anaesthetic and anti-inflammatory (low dose steroid) around the dorsal root ganglion. The ganglion looks like a small swelling on the nerve that joins the spinal cord. This ganglion contains nerves that carry sensation. It may also be called a nerve root injection. DRG blocks are used mainly for localized radicular pain (sciatica) pain when conservative management has not helped. The injection may sometimes be referred to as nerve block or a transforaminal block.

Pain relief can be short-lived although some people can get significant and lasting pain relief from these injections. The injection is usually undertaken alongside other treatments such as physiotherapy.