In some low back pain programs, if three facet block injections provide good but temporary relief of the patient’s pain, a facet rhizotomy injection may be recommended. The purpose of a facet rhizotomy injection is to provide lasting low back pain relief by disabling the sensory nerve that goes to the facet joint. This is a straightforward procedure that is normally carried out if you have had a successful result from facet joint injections. Special needles are carefully placed under continuous fluoroscopy so that their tips lie exactly on the nerves that carry pain signals from the facet joints. Radiofrequency energy is then passed through the needles so that that tissue at the tip is heated to about 80 degrees C for about a minute. This coagulates and inactivates the nerves.