Coding Conundrum: Coding for Facet Cyst Aspiration

Question:

We are confused by AMA recommendations for the aspiration of a facet cyst. While researching, we found two CPT Assistants (2011 and 2017) advising to use an unlisted code, 64999. The Clinical Examples in Radiology CPT Assistant, February 2024 instructs to use CPT code 22899, not 64999. The rationale cited for recommending CPT code 22899 is because the procedure does not involve entering the facet joint and facet cysts are not considered to originate in the nervous system.

Which unlisted code does KZA recommend?

Answer:

Thank you for your detailed inquiry. We understand your confusion. KZA noted this discrepancy earlier this year while researching whether the AMA had published the updated guidance since the 2017 article.

KZA appreciates that both sources recommend an unlisted code. CPT code 64999 represents an unlisted procedure within the nervous system, while CPT code 22899 applies to unlisted spinal procedures

According to the latest guidance outlined in Clinical Examples in Radiology, Fall 2024, KZA recommends CPT code 22899 (unlisted procedure, spine) as the most appropriate code for aspiration of a facet cyst.

*This response is based on the best information available as of 9/25/25.

Excisional Debridement (1104x) vs. Surgical Preparation (1500x)

Question:

Our surgeon is taking a patient to the OR to excise a surgical wound dehiscence, which will be closed with a skin graft. We are looking at debridement codes 1104x and the skin graft codes (15xxx). Are we on track?

Answer:

Thank you for reaching out to KZA!

You're on the right track with the skin graft codes (15xxx series). However, for the debridement portion, it's important to note that the 1104x codes are typically used when the wound is being debrided with the expectation of healing by secondary intention—that is, without primary closure or grafting.

In your scenario, since the wound will be closed with a skin graft, the more appropriate coding would come from the surgical preparation code set (15002–15005). These codes are specifically intended for excisional preparation of a wound bed before grafting or other definitive closure.

*This response is based on the best information available as of 9/25/25.

Reporting Modifiers with Unlisted Codes

Question:

Can modifiers be reported with unlisted CPT codes?

Answer:

Yes, modifiers can be appended to unlisted CPT codes.

In 2024, CPT clarified this by updating the introduction guidelines for unlisted procedures and services. These updates were further explained in the January 2024 issue of CPT Assistant, which addressed the new and revised text and the standardization of reporting unlisted CPT codes across the CPT code set.

Illustration of modifiers that may be appropriately applied includes:

• Laterality modifiers – e.g., RT (right), LT (left)

• Bilateral procedure modifier – 50

• Role-based modifiers – e.g., 62 (two surgeons), 80 (assistant surgeon), 82 (assistant surgeon when qualified resident not available), AS (non-physician surgical assistant)

• Multiple or distinct procedure modifiers – e.g., 51 (multiple procedures), 59 (distinct procedural service)

• Global modifiers – e.g., 58 (staged or related procedure), 78 (return to operating room for related procedure), 79 (unrelated procedure or service)

This is not an all-inclusive list of modifiers that may be appropriately applied to unlisted CPT codes. For complete and up-to-date information, one should refer to current CPT guidelines and payer-specific policies.

Please note: Modifiers that describe an alteration of a service or procedure, such as modifier 52 (reduced services), are not appropriate for use with unlisted codes. The same applied to modifier 22 (increased procedural services).

*This response is based on the best information available as of 9/22/25.

Complex Close with FTSG

Question:

We want to confirm with KZA if a complex closure with extensive undermining is required to close the donor site where an FTSG was taken. Can we separately report the closure?

Answer:

No, this is not separately reportable. The CPT descriptors for the full-thickness skin grafts (FTSG) code set specifically state “including direct closure of the donor site”.

*This response is based on the best information available as of 8/28/25.

Cryoablation of Genicular Nerve

Question:

I'm new to coding pain management procedures. My provider plans to begin performing cryoablation of the genicular nerve under ultrasound guidance. What is the correct way to code this procedure?

Answer:

Great question! The appropriate CPT code for this procedure is 64624 Destruction by neurolytic agent, genicular nerve branches including imaging guidance, when performed. This code encompasses all methods of nerve destruction, including cryoablation, as well as radiofrequency, thermal, chemical, and electric techniques.

To report CPT 64624 correctly, documentation must reflect destruction of all three key genicular nerve branches:

• Superolateral

• Superomedial

• Inferomedial

If the provider does not treat all three branches, you must append modifier 52 to indicate reduced services. Also, while imaging guidance is included in the code, make sure the medical record documents its use to support the procedure.

*This response is based on the best information available as of 8/28/25.

Infected Total Shoulder Arthroplasty

Question:

Could KZA help me with an orthopedic surgery coding question? Thank you in advance. What code should be used if the provider performed irrigation and debridement with polyethylene exchange in an infected total shoulder?

Answer:

Thank you for your question. Without reviewing the operative note, KZA cannot address a specific case but can help you with general guidelines.

CPT Assistant from September 2021 addresses scenarios for revision arthroplasty. These scenarios are for the hip and knee but are relevant to all other joint arthroplasty procedures, and the same logic is applied to joints outside of the hip and knee.

If there is an exchange of a component in a TJA, CPT Assistant September 2021 guidelines state “when only a single modular component is revised, report the single component with modifier 52.” Therefore, based on your question, (not reviewing the operative note), it is appropriate to code for a single component revision of (23473) appending modifier 52, Reduced Services.

*This response is based on the best information available as of 8/28/25.