Question: Our surgeon documented that he administered a nerve block to the left side of C3 through C7. How many levels do we consider this when coding? Pennsylvania Subscriber Answer: Base your coding on the facet joint level rather than the individual nerves treated. Facet joint nerves C3 and C4 innervate the C3-C4 facet joint. So you would report a nerve block to this joint with 64470 (Injection, anesthetic agent and/or steroid, paravertebral facet joint or facet joint nerve; cervical or thoracic, single level). The C4 and C5 facet joint nerves innervate the C4-C5 facet joint, the C5 and C6 facet joint nerves innervate the C5-C6 facet joint, and the C6 and C7 facet joint nerves innervate the C6-C7 facet joint. Report blocks to each of these facet joints using +64472 (- cervical or thoracic, each additional level [list separately in addition to code for primary procedure]). Your final claim should include 64470 once, plus three units of 64472.