Spine surgery can be a complex, confusing specialty to code. Rather than selecting a single code that describes the whole operation, your coders must adopt an a la carte approach to coding spine cases. It's not uncommon for 5 different types of codes to be reported during a single spine operation. And depending on the extent of the surgery, there could be 10 or 12 CPT codes.

Take, for example, single-level anterior cervical decompression/ discectomy and fusion, a very common outpatient spine case. At a minimum, this 2-hour case would require 4 CPT codes. You'd have a code for the decompression/discectomy, a second code for the fusion, a third code for a bone graft or intervertebral device and a fourth code for the plate. There may even be a fifth code for a different type of bone graft.

Rules to code by
I've put together some general principles of spine surgery coding that will help guide your coders:

1. Stand-alone vs. add-on codes. When the procedure crosses a spinal junction (C7-T2, for example), report a single stand-alone code and appropriate add-on codes (for example, 22554 and 22585) rather than 2 stand-alone codes (for example, 22554 and 22556). Always use a stand-alone CPT code rather than an add-on code to report the primary or first level activity. Add-on codes are designated in CPT by the "plus" sign (+) and are used to report additional level spine procedures.

2. Anterior vs. posterior. Knowing whether the procedure is performed on the anterior or the posterior spine drives the codes that you're going to use. Look in the procedure statement of the operative report, or in the first or second paragraph, to determine which approach was used. You can also tell by the way the patient was positioned on the OR table — it's a posterior spine procedure if the patient was in the prone position and an anterior spine procedure if the patient was placed in the supine position.

• Code posterior instrumentation based on the number of attachments on the spine and number of vertebral segments the instrumentation spans.
  22840 Posterior non-segmental instrumentation (Harrington rod technique), pedicle fixation across 1 interspace, atlantoaxial transarticular screw fixation, sumlaminar wiring at C1, facet screw fixation
  22842 Posterior segmental (pedicle fixation, dual rods with multiple hooks and sublaminar wires); 3 to 6 vertebral segments
  22843 7 to 12 vertebral segments
  22844 13 or more vertebral segments
• Code anterior instrumentation based on the number of vertebral segments the instrumentation spans:
  22845 2 to 3 vertebral segments
  22846 4 to 7 vertebral segments
  22847 8 or more vertebral segments

3. Instrument and bone graft codes. Spinal instrumentation and spinal bone graft codes are add-on codes and should not be reported with modifier —62 (co-surgery modifier). These codes (20930, 20931, 20936, 20937, 20938) represent the physician work involved in preparing and harvesting the bone graft; the fusion codes include the value for placing the bone graft. Per CPT, bone graft codes may be reported once per operative session, not necessarily once per spinal interspace or segment fused.

6 categories of spine codes
You may report 6 types of codes for spine procedures.

1. Decompression/discectomy procedure. Report a stand-alone decompression/discectomy code for the first spinal level performed. Report subsequent levels using an add-on code. From the posterior spine, the codes include a laminectomy or hemilaminotomy. On the anterior spine, the codes state decompression "including discectomy" so make sure the operative report clearly reflects the decompression activity.

2. Arthrodesis/fusion. Choose a stand-alone procedure code for arthrodesis/fusion.

The most common outpatient spinal fusion procedure will be on the anterior cervical spine using CPT 22554. On the posterior spine, the more common procedures include the posterolateral fusion (22612) and the interbody fusion (22630). The additional level code for posterolateral fusion is 22614, while the additional level code for the interbody fusion is 22632.

3. Spinal instrumentation. Choose an add-on code for the instrumentation or fixation. Remember that instrumentation and bone graft codes are add-on codes and are not reported with modifier —62.

Choose the correct code depending on the number of vertebra the instrumentation spans or the number of attachments on the spine depending on whether the instrumentation is placed on the anterior or the posterior spine. On the anterior spine, use 22845 when instrumentation spans 2 to 3 vertebral segments (C6 to C7 or C5 to C7). Use 22846 when the instrumentation spans 4 to 7 vertebral segments such as in a 3-level anterior cervical fusion (C4-C7).

In the posterior spine, use 22840 for non-segmental instrumentation where there are only 2 points of fixation, or attachment, on the spine (L4 to L5 pedicle screws and rods, for example). Use 22842 for posterior segmental instrumentation where there are at least 3 points of attachment on the spine (pedicle screws and rods at L4, L5 and S1, for example); count the vertebral segments and use this code for instrumentation that spans 3 to 6 segments.

The intervertebral device code (22851) is used for a biomechanical device in the interspace. Report the code once per interspace or vertebral defect, not necessarily once per device. For example, even though 2 devices were placed in the interspace, use 1 code to report 2 PEEK (polyether-etherketone) devices placed in the L5-S1 interspace.

4. Bone graft codes. Oftentimes spine surgeons don't dictate the bone grafts using CPT language. Remind your physicians that it's important that they at least document the trade name or brand name of the bone graft used so that you can choose the correct code(s).

CPT describes 2 types of bone grafts: allograft (donor bone) and autograft (patient's own bone). Bone graft codes are described in CPT as being either morselized or structural. These codes represent the physician work involved in preparing and harvesting the bone graft to be used for the fusion/arthrodesis.

These codes may be reported once per operative session, not once per interspace or level of fusion. Codes 20937 and 20938 typically represent bone harvested from the patient's iliac crest while 20936 represents patient bone harvested through the same surgical exposure (crushed lamina or spinous process bone).

There are 2 allograft codes; 20931 is for a structural allograft, which is typically a wedge or a piece of cadaver bone, while 20930 represents crushed allograft.

5. Other codes. For more than 1 level of spine, you'll report the additional level codes or the decompression/discectomy and fusion as appropriate. Additional spinal levels are represented by add-on codes (63076 for an additional anterior cervical decompression/discectomy). The use of the operating microscope for microdissection is reported using 69990 (except CPT says this activity is included in 63075-63078 and not separately reported). While CPT lets you report 69990 with some spine procedure codes, Medicare's payment rules may not allow reimbursement. For example, a lumbar microdiscectomy would be reported using 63030 and 69990. However, Medicare's Correct Coding Initiative Edits will preclude payment on the 69990 on this example.

6. HCPCS supply codes. The facility can separately report a HCPCS code for a spinal implant, but many payors may not provide separate reimbursement.