A genicular nerve block is a diagnostic procedure to help determine the source of your knee pain and a therapeutic procedure to relieve your pain. If you have chronic knee pain that has not responded to conservative care, you may be a candidate for a genicular nerve block, in which the nerves are anesthetized with a local anesthetic injected through small needles. Genicular nerve radiofrequency ablation may be offered for longer-lasting relief if you have a positive response to the nerve block.