Neurosurgery Coding Alert

When reporting same-session arthrodesis, be careful not to mix -segments- and -interspaces-

Reporting spinal instrumentation is fairly straightforward--as long as you know the location and type of instrumentation. In part 1 of this two-part series, we discuss the first five of nine ways you can ensure accurate instrumentation coding every time. 1. Select Instrumentation Codes First by Location When you choose CPT codes for instrumentation, location--rather than the type of device--is the most important selection criterion.

The breakdown: Instrumentation may be described as anterior (attaching to the front portion of the spine or vertebral segment, toward the -center- of the body) or posterior (attaching to the back of the spine or vertebral segment, facing toward the back), and can consist of rods, cages, plates, wires and/or other mechanical devices, says Linda Parks, MA, CPC, CMC, CMSCS, an independent coding consultant in Atlanta.

You may further classify posterior instrumentation as segmental or nonsegmental.

Tip: Generally, the type of instrumentation will correspond to the surgical approach (anterior or posterior). And the surgeon's documentation should explicitly state the type of instrumentation he places. If the surgeon's op report does not specify, be sure to ask. 2. For Posterior, Determine Segmental or Not If the surgeon places posterior instrumentation, you must further determine if the device is segmental (22842-22844) or nonsegmental (22840). The surest way to do this is to count the number of fixation points, Parks says:

- If the surgeon attaches the instrumentation to the spine at only two points, the device is nonsegmental (regardless of the number of vertebrae spanned).

- If the surgeon attaches the device to at least three points (on three different segments), the instrumentation is segmental. 3. Only Segments Matter for Anterior Instrumentation You should report placement of anterior instrumentation using 22845 (Anterior instrumentation; 2 to 3 vertebral segments), 22846 (- 4 to 7 vertebral segments) or 22847 (- 8 or more vertebral segments), depending on the number of vertebral segments spanned (there is no distinction between segmental and nonsegmental anterior instrumentation).

Example: The surgeon places anterior instrumentation from C6 to T3. This involves five spinal segments (C6, C7, T1, T2 and T3). Therefore, you would apply 22846.

Tip: Anterior instrumentation usually involves application of plates that the surgeon screws directly onto the vertebrae, whereas posterior instrumentation usually involves placement of rods and either hooks that grip the lamina or screws that engage the pedicles, says Gregory Przybylski, MD, director of neurosurgery at the New Jersey Neuroscience Institute, JFK Medical Center in Edison. 4. Count Levels and Interspaces Carefully Because CPT defines codes for segmental and non-segmental (both anterior and posterior) instrumentation according to the number of vertebral segments involved (for example, 22842 specifies -... 3 to 6 vertebral segments-), you must count your vertebrae [...]