When a facet joint injection and medial branch blocks are performed in the same setting, you would count the number of levels per facet joint levels treated. As seen below in AMA CPT Assistant 2004 article they point out:
".... each facet joint has dual innervation: one from the dorsal rami at the same level and one from the level above (eg, the L4-L5 lumbar facet joint is innervated by the medial branches of the dorsal rami from L3 and L4"
So in your example, L4 and L5 medial branches would innervate the L5-S1 level which also received an injection directly into the joint. This would account for one level even though two procedure techniques were required. This could be reported as 64493 with the LT modifier. Then additional CPT 64494 would be reported for the facet joint injection into the L4-5 Joint. In order to report 64495, you would of needed treatment of a third level such as L3-4. So your current example would only represents a two level block based on the number of facet joint levels that were treated.
__________________________________
AMA CPT Assistant 2010
Question: Lumbar medial branch blocks were performed on the right at L3, L4, and L5. Would codes 64490, 64491, and 64492 be reported because three different levels were injected?
Answer: No. The L3, L4, and L5 medial branch nerves innervate the L4-L5 and L5-S1 facet joints. Therefore, code 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, is reported for the first joint injected or blocked (L4-L5). Code 64493 is reported for a single or initial level treated. Add-on code 64494, Injection(s), diagnostic or therapeutic agent, paravertebral facet (zygapophyseal) joint (or nerves innervating that joint) with image guidance (fluoroscopy or CT), lumbar or sacral; second level (List separately in addition to code for primary procedure), is reported for the second joint or level injected or blocked (L5-S1). In this specific instance only, CPT codes 64493 and 64494 should be used, provided the injections were performed in the lumbar spine with fluoroscopic (or CT) guidance, as required to use codes 64490-64495.
To further clarify, add-on code 64495, Injection(s), diagnostic or therapeutic agent, paravertebral facet (zygapophyseal) joint (or nerves innervating that joint) with image guidance (fluoroscopy or CT), lumbar or sacral; third and any additional level(s) (List separately in addition to code for primary procedure), is reported only once per day for injections at the third and any additional lumbar or sacral level(s) treated (which does not apply to this case). Codes 64494 and 64495 should only be used in conjunction with code 64493......
AMA CPT Assistant 2004 (Excerts---Not in original order of article/Codes have been updated)
It should be further emphasized that codes 64475, 64476, 64479, and 64480 refer to the injection of a facet joint either by injection into the joint with one needle puncture or by anesthetizing the two medial branch nerves that supply each joint (two needle punctures). For example, a left-sided L4-L5 intra-articular injection performed with a single needle puncture would be coded as 64475. Injection of the L3 and L4 medial branch nerves supplying the L4-L5 facet joint would also be coded as 64475, even though two separate injections are performed to effect the same result.
Facet Joint Nerve Anatomy
Each facet joint is supplied by two medial branch nerves. As each main spinal nerve exits the spine and passes through the intervetebral foramen of the spine, it gives off a branch (posterior primary ramus) that supplies the structures at the back of the spine, while the main spinal nerve (anterior primary ramus) continues onward to supply peripheral structures. The posterior primary ramus then typically divides into three branches: medial, intermediate, and lateral. Each medial branch supplies sensation to one half of each facet joint above and below the spinal nerve of origin, the multifidus muscle, the spinal ligaments, and a small area of skin in the midline of the back. The intermediate and lateral branches supply back muscles farther away from the midline.
Generally, each facet joint has dual innervation: one from the dorsal rami at the same level and one from the level above (eg, the L4-L5 lumbar facet joint is innervated by the medial branches of the dorsal rami from L3 and L4).
Single vs Multiple Needle Injection Technique
The lumbar facet injection codes (64475 and 64476) and cervical/thoracic facet joint injection codes (64479 and 64480) are reported once when the injection procedure is performed irrespective of whether a single or multiple puncture is required to anesthesize the target joint at a given level and side. Commonly, physicians use a technique that involves insertion of the needle once, with attachment of a short piece of extension tubing through which the first drug is injected. The syringe is then changed, and the next drug is injected through the same tubing/needle. Should the physician choose to perform separate needle punctures, this multiple needle technique does not alter reporting. To clarify, only one facet injection code should be reported at a specified level and side injected (eg, right L4-5 facet joint), regardless of the number of needle(s) inserted or number of drug(s) injected at that specific level.
