Neurosurgery Coding Alert

Question: Encounter notes indicate that the provider performed chemodenervation of three muscles in the patient’s right leg and five muscles in the patient’s right arm. How should I report this encounter?

North Dakota Subscriber

Answer: On the claim, report:

• 64644 (Chemodenervation of one extremity; 5 or more muscles) for the arm chemodenervation.
• Modifier RT (Right side) appended to 64644 to indicate laterality.
• 64642 (… 1-4 muscle(s)) for the leg chemodenervation.
• Modifier RT appended to 64642 to indicate laterality.

Code order explained: You’d want to report 64644 first because it’s the higher-paying code: 5.31 nonfacility relative value units (RVUs) versus 4.52 RVUs for 64642. Even when it’s not a huge discrepancy in payout, it’s still best practice to always report the highest-paying code first.