Get the facts on spinal fusion, instrumentation, and grafts

Editor’s note: This is the second article in a two-part series on spinal surgery coding. In this article, we will focus on fusions, instrumentation, and spinal grafts. In part one, we introduced the basic elements of a spinal surgery and took a closer look at decompression procedures.

A surgeon performs an arthrodesis of lumbar vertebrae L1–L2. What are the appropriate codes to report for this procedure? Would it be CPT® code 22612 (arthrodesis, posterior or posterolateral technique, single level; lumbar) or code 22612 and add-on code 22614 (each additional vertebral segment)?

A surgeon performing an arthrodesis fuses two bones together to stabilize the spinal motion unit. It is not possible to fuse a bone to itself, says Kim Pollock, RN, MBA, CPC, consultant and speaker with Karen Zupko & Associates, Inc., in Chicago. The least a surgeon can do is fuse one segment to another.
Here’s where the disconnect between code descriptions and the terminology surgeons use comes into play. Two vertebrae and the tissues that connect them make up the smallest working unit of the spine. This unit is sometimes referred to as a spinal motion unit. To a spinal surgeon, a segment is two movable units. To a coder, a segment indicates one bone.

So when it comes to choosing the correct CPT code for a spinal fusion, coders almost have to count interspaces instead of vertebrae to choose the correct code, Pollock says. For the case above, report only code 22612.

Take into account the reason for the fusion
When coding a spinal fusion, consider the reason for the procedure. Review the documentation to determine whether the physician performed the fusion for deformity, pain, or instability, says Kristi Stumpf, MCS-P, CPC, COSC, ACS-OR, senior orthopedic coder and auditor for The Coding Network based in Beverly Hills, CA.

For a fusion for spinal deformity (e.g., scoliosis or kyphosis), coders should look to codes 22800–22819. This code series was created for, and intended to be used for, fusion procedures performed on younger patients with congenital spinal deformities, not for degenerative scoliosis, says Stumpf.

If the surgeon is performing the fusion for pain or instability, coders should reference one of the following code series:

  • 22532–22534 (lateral extracavitary)
  • 22548–22585 (anterior or anterolateral)
  • 22590–22632 (posterior)

Identify the approach used in the procedure
Surgeons can use various approaches when performing a spinal fusion. Carefully read the documentation to find which approach the surgeon used, then choose the code that reflects that approach. Consider the following approaches:

  • Lateral extracavitary (codes 22532–22534)
  • Anterior or anterolateral (codes 22558–22585, 22808–22812)
  • Posterior or posterolateral or lateral transverse process (codes 22590–22632, 22800– 22804

"Keep in mind that each of these approaches is coded with a different series of codes,” Stumpf says. “You need to understand your approaches. If you don’t, take time to pull them up on the web and see what structures [the surgeon] would be going through, so you can tell exactly what the approach is.” If all else fails, query the physician.

Also note that if the physician documents “direct lateral approach” for spinal fusion, coders should code it as an anterior approach per the North American Spinal Society and the American Association of Neurological Surgeons.

Note the spinal instrumentation
A surgeon may place instrumentation in the spine as part of the fusion procedure. Report the appropriate add-on code based on approach and instrumentation:

  • 22840–22844 (posterior instrumentation)
  • 22845–22847 (anterior instrumentation)
  • 22848 (pelvic fixation)

Surgeons may use a biomechanical device, such as:

  • Polyether ether ketone (PEEK) devices (e.g., Mosaic, LDR, GraftCage, Capstone, Zero-P, STALIF, Solitaire)
  •  HARMS cage
  • BAK cage
  •  Methylmethacrylate (i.e., bone cement)

Report the application of the above listed intervertebral biomechanical device(s) using add-on code 22851. Note that coders should report code 22851 per interspace or vertebral defect, not per device, says Pollock. Append modifier -59 (distinct procedural service) for each code that indicates an additional interspace.

Although polyether ether ketone (PEEK) does not really fit the definition of a biomechanical device, coders should report it using code 22851, Stumpf says. Report all structural allografts using code 20931, so they need to pay careful attention to what the device is made of in order to bill biomechanical devices correctly, says Stumpf.

Consider the type of bone graft
Allograft is bone obtained from a donor—not from the patient (i.e., autograft). An allograft bone contains no living cells. Think of an allograft as bone in a bottle or a package. Coders should report all bone graft codes only once per surgery with, Pollock says.

The bone graft codes include:

  • 20930 (allograft or osteopromotive material for spine surgery, morselized)
  • 20931 (allograft for spine surgery, structural)
  • 20936 (autograft, local) 
  • 20937 (harvest of graft through separate skin incision, commonly iliac crest)
  • 20938 (autograft, structural, bicortical, or tricortical)

Coders should only report each bone graft code performed only once per operative session.

Bear in mind other factors
Once coders locate the fusion, instrumentation, grafts, and decompression if the physician performed it, they need to look for some additional elements.

Look to see whether the surgeon used a microscope for microdissection or microsurgical techniques. But note that some carriers—Medicare and private payers who follow Medicare guidelines—will not pay for the use of a microscope, Stumpf says.

However, other private payers will. So for those cases, follow CPT guidelines for reporting the use of the microscope, which are completely different from the National Correct Coding Initiative (NCCI) edits, she says. CPT guidelines instruct coders to report the microscope use, and CPT lists specific codes with which it should not be reported. However, NCCI edits bundle the microscope into the procedure code.

To report use of the microscope, however, physicians must document that they used it for a microsurgical technique and not just for magnification or illumination, Pollock says.

Also remember that CPT guidelines do not prohibit coders from reporting the use of a microscope for a discectomy or laminectomy, Pollock adds. Coders should report the use of the microscope even when the payer won’t reimburse for it because it is an appropriate CPT combination.

Medicare also sometimes reverses the NCCI edits, Pollock adds. “If you didn’t bill for it originally, you won’t be able to file for a redetermination.”

When the surgeon uses a microscope for microdissection, report CPT add-on code 69990 (use of operating microscope) separately in addition to the code for the primary procedure.

When coding for the microscope used for microdissection or microsurgical techniques, coders need to see documentation of the work involved in bringing the microscope into the field, leaving the field, and during the procedure, Stumpf says. The same holds true for the use of stereotactic navigation. The provider needs to set up, use, and document the use of the instrumentation to support the coding.

E-mail your questions to Senior Managing Editor Michelle A. Leppert, CPC-A, at

Interested in learning more about spinal coding? Shelley C. Safian, PhD, MAOM/HSM, CCS-P, CPC-H, CPC-I, CHA, AHIMA-approved ICD-10-CM/PCS trainer of Safian Communications Services and Kristi Stumpf, MCS-P, CPC, COSC, ACS-OR, senior orthopedic coder and auditor for the The Coding Network based in Beverly Hills, CA, discuss ICD-9-CM and CPT coding for spinal procedures during HCPro’s July 28 audio conference, “Spinal ICD-9 and CPT Coding: Get the Complete Picture for Accurate Reimbursement”. To learn more or to purchase, go to the HCMarketplace Web site.

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