Neurosurgery Coding Alert

Question: The neurosurgeon performs anterior interbody fusion at C5-C6 for a patient with degenerative cervical disc disease (722.4, Degeneration of cervical intervertebral disc). He also places a Cornerstone fibular allograft and plate. I know that 22554 describes the fusion, but what about the allograft? Is this a structural graft or a "biomechanical device"?

Maryland Subscriber

Answer: As you indicate, you should begin by reporting 22554 (Arthrodesis, anterior interbody technique, including minimal discectomy to prepare interspace [other than for decompression]; cervical below C2) for the fusion, along with any included discectomy.

To describe placement of a plate, turn to 22845 (Anterior instrumentation; 2 to 3 vertebral segments). This code is modifier 51 (Multiple procedures) exempt, and you can report it without adding modifiers or expecting a "multiple procedure" reimbursement reduction.

For the allograft, you have three code choices:

Often, the words your neurosurgeon uses in her documentation will help you decide which code is appropriate. Specific terms you may see include: VG2 bone graft, interbody spacer, Cornerstone graft, mechanical spacer, Brantigan cages, VG2 allograft, Pyramesh cage, Pyramid ovoid mesh, PEEK cages, allograft interbody spinal implants, Osteotech interbody spacer, VG2 lordotic spacer, Medtronic Verte-Stack Cornerstone, Harms cage, and titanium mesh vertebral body replacement.

The AMA clarified in the February 2005 CPT Assistant that the only allograft that qualifies for 22851 is threaded bone dowels. "All other bone allografts are structural allografts and should be reported with CPT code 20931," the article explains. You should use 20930 for any morselized allografts.

You would also report 22851 when the neurosurgeon places a cage, the ovoid mesh or the titanium mesh.

In the case you describe in your question, therefore, the appropriate code for the allograft is 20931. Medicare guidelines state that you should report 20931 only once per surgery, regardless of how many grafts of that type the surgeon places.