It is the injection of drugs (local anaesthetic and/ or opiate analgesic or corticoid) in a place of your spinal, cervical, dorsal or lumbar column, which acts directly in the closest area to the spinal cord, specifically around it. This specific space is called the epidural space. This infiltration temporarily relieves inflammation or pain depending on the location of the pain: the neck, shoulders and arms, thorax and abdomen or the lumbar region, pelvis and legs.