January 10th, 2018
According to Medicare article A50443, a facet joint is supplied by two medial branch nerves. Each medial branch nerve supplies sensation to one half of each facet joint above and below the spinal nerve of origin. Therefore, both of the two related medial nerve branches for each facet joint must be treated.
The CPT codes 64635-64636 have a bilateral surgery indicator of "1." Thus, they are considered “unilateral” procedures and the 150% payment adjustment for bilateral procedures applies.
- When denervating a facet joint/nerve unilaterally, file the appropriate anatomic modifier, –LT or –RT.
- When denervating a facet joint/nerve bilaterally at the same level, file with modifier –50.
- One (1) unit of service may be submitted for each level of nerve denervation. For example, destruction of L3 and L4 medial branch nerves would be coded as 64635 and 64636.
Whether a paravertebral facet joint/nerve denervation is performed unilaterally or bilaterally, use CPT code 64635 or 64636 for the first level denervated. If a second level is denervated unilaterally or bilaterally, use CPT code 64636 or 64634.
Injecting any denervation agent through the needle, including small amounts of contrast or anesthetic to confirm the position of the needle is considered an integral part of the procedure and is not separately reimbursed. Neither the injection procedure nor the anesthetic or denervation agent drugs should be billed.