Eli's Rehab Report

Append modifier 59 to 95900 to show motor tests on separate nerves

If you’ve found no relief when trying to figure how payers want nerve conduction studies (NCS) reported, your life just got easier, thanks to CPT 2006’s Appendix J.
This appendix lists which nerves count as separate “units,” making coding guidelines concrete when you are identifying the correct type and number of NCS codes to report

Report 1 Unit per Listed Nerve

For each separately reportable nerve you test, you may report one unit of service of the corresponding NCS code, says Neil Busis, MD, director of the neurodiagnostic laboratory at the University of Pittsburgh Medical Center at Shadyside. The AMA has arranged the list of nerves by type (motor or sensory/mixed) and location (upper extremity, lower extremity, cranial nerves and trunk, and root stimulation).

“I think this method should make billing for NCS much easier for most coders,” Busis says. “Determining the correct number of separately billable studies should now be as simple as consulting a list.”

This method may counter the way your physiatrists are used to determining the number of separate nerve conduction studies. In the past, your physiatrist may have used the “definition” of separate nerve to be any time that he moved both the stimulating and recording electrodes, even if along the same nerve. But you probably had difficulty confirming this because your physiatrist’s documentation did not clearly indicate the electrode movement. But CPT now spells out the way that many specialty societies and the CPT Assistant recommend that you code these procedures.

“It will be interesting to see how insurers respond to the new coding guidelines,” says Randall Karpf, owner of East Billing in East Hartford, Conn. “They may start requesting proof that your [physiatrist] addressed separate nerves if you report more than one unit of any particular NCS code.”

Key: The inclusion of these guidelines in the CPT Codes book (rather than just a past CPT Assistant article) will help you with inappropriate code and/or unit(s) denials.

You’ll also find the “Type of Study/Maximum Number of Studies” table in Appendix J. This table can help you substantiate the multiple electrodiagnostic testing units you can have for the various diagnoses.

Make Your Case With Modifiers When Mixing Studies

You can report more than one type of NCS at the same time--and even multiple units of each type of study--as long as each study occurs on a separately billable nerve and you meet medical-necessity requirements for the services provided.

Example: Your physiatrist performs a motor NCS with F-wave on the ulnar nerve to the abductor digiti minimi, a motor study without F-wave on the ulnar nerve to the first dorsal interosseous, and a sensory NCS on the ulnar dorsal cutaneous sensory nerve.

In this case, if you check the list of nerves, you find that each of these nerves counts as a separate unit. Therefore, you should report 95900 (Nerve conduction, amplitude and latency/velocity study, each nerve; motor, without F-wave study) for the ulnar nerve to the first dorsal interosseous, 95903 (… motor, with F-wave study) for the ulnar nerve to the abductor digiti minimi, and 95904 (... sensory) for the ulnar dorsal cutaneous sensory nerve.

If you stop your coding there, however, don’t be surprised to see reduced reimbursement or code denial. Many carriers will look at the claim and think you’re trying to bill multiple motor studies for the same nerve, Busis says. Appending modifier 59 (Distinct procedural service) to the lesser study (95900) can help to clarify to your payer that the motor tests occurred on separate nerves.