Anesthesia Coding Alert

Question: How should we code for a medial branch block (MBB) of L2-3, L3-4, and L4-5?

Virginia Subscriber

Answer: Some patients may require a targeted medial branch nerve block rather than a regular facet joint block. Each facet joint is supplied by the medial branches of two different spinal nerves. For example, the facet joints at L2-L3 are supplied by medial branches from the L1 and L2 spinal nerves. For this reason, the physician must block two median nerves for each facet joint. In the case of a medial branch nerve block at L2-L3, for example, the physician would inject the medial branches of L1 and L2. For coding purposes, these two injections are considered a single injection service.

The following codes are used for facet joint injections and medial branch nerve blocks:

• 64493 – Injection(s), diagnostic or therapeutic agent, paravertebral facet (zygapophyseal) joint (or nerves innervating that joint) with image guidance (fluoroscopy or CT), lumbar or sacral; single level
• 64494 – … second level (List separately in addition to code for primary procedure)
• 64495 – … third and any additional level(s) (List separately in addition to code for primary procedure).

Note: CPT^® includes several anesthesia codes for procedures in the lumbar region. These include:

• 00630 – Anesthesia for procedures in lumbar region; not otherwise specified
• 00632 – … lumbar sympathectomy
• 00635 – … diagnostic or therapeutic lumbar puncture 
• 00640 – Anesthesia for manipulation of the spine or for closed procedures on the cervical, thoracic or lumbar spine.