CPT code 64624 – Genicular nerve ablation

Key takeaways

CPT 64624 covers neurolytic destruction of the superolateral, superomedial and inferomedial genicular nerve branches of one knee.

Report one unit per knee, whatever the branch count. Append modifier 52 when fewer than three branches are destroyed.

Imaging guidance is part of the code, so 76942, 77002 and 77012 never go on the same claim.

CPT 64625 is a sacroiliac joint ablation code, not an add-on for extra genicular nerves.

Noridian’s Medicare article A59752 says iovera cryoneurolysis is not destructive and should not be billed as 64624.

CPT code 64624: Official descriptor and procedure overview

CPT code 64624 is defined by the American Medical Association (AMA) as destruction by neurolytic agent, genicular nerve branches including imaging guidance, when performed. It is the code for genicular nerve ablation of the knee, most often done for chronic osteoarthritis pain. The code has carried this descriptor since the 2020 CPT code set.

One unit of 64624 covers destruction of three named branches of one knee: the superolateral, superomedial and inferomedial genicular nerves. There is no add-on code for each extra nerve. When fewer than three branches are destroyed, the physician appends modifier 52 for a reduced service.

What procedures does CPT 64624 cover?

CPT 64624 covers any technique that destroys the genicular nerve branches, so the nerve stops carrying pain signals until it regrows. The patient lies supine, and the physician uses fluoroscopy or ultrasound to place a needle or probe beside each branch.

Three destruction methods fall under the code:

• Conventional radiofrequency ablation (RFA): the probe heats the nerve to create a thermal lesion.
• Cooled radiofrequency ablation: a water-cooled probe creates a larger lesion around the same targets.
• Chemical neurolysis: alcohol or phenol is injected to destroy the nerve. It is less common at the knee.

The operative note must name the method, the branches treated, the side and the imaging used. The same code applies whichever destructive method is chosen, subject to the payer’s coverage policy.

What CPT 64624 does not cover

The code is limited to destruction of the genicular branches, so several neighboring knee and nerve procedures need a different code:

• Diagnostic or therapeutic genicular nerve block: an anesthetic or steroid injection into the same branches reports CPT 64454. NCCI edits do not allow 64454 with 64624 at the same session.
• Pulsed radiofrequency: CPT guidelines say destruction codes are not reported for therapies that do not destroy the nerve. Pulsed RF goes to unlisted code 64999.
• Cryoneurolysis with iovera: Noridian classes the device as non-destructive and points Medicare claims to Category III code 0441T instead.
• Other peripheral nerves: destruction of a peripheral nerve or branch outside the genicular group reports 64640.
• Sacroiliac joint ablation: radiofrequency ablation of the nerves supplying the sacroiliac joint reports 64625.

CPT 64624 vs related codes: Side-by-side comparison

Most cross-coding errors on 64624 come from three mix-ups. Coders treat 64625 as an add-on, bill the diagnostic block on the same claim, or report a non-destructive technique as destruction. The table sets out where each neighboring code applies.

A single-knee ablation of all three branches bills as 64624 x1. If only two branches are destroyed, it bills as 64624-52 x1. Ablation of both knees in one session bills as 64624-50 with one unit, or with RT and LT lines where the payer asks for them. The diagram below runs through the four questions that decide each claim line.

Imaging guidance with CPT 64624: Why 76942 and 77012 are not billed

Imaging guidance is written into the 64624 descriptor, so it is never billed on a separate line. NCCI edits block fluoroscopy, CT, ultrasound and MRI guidance codes with 64624, including 76942, 77002 and 77012.

The phrase “when performed” means the code pays the same with or without imaging. Document the modality anyway, because payer coverage policies for genicular ablation usually expect image guidance.

Modifiers for CPT 64624: Reduced service, bilateral and laterality

Because 64624 is defined per knee, the modifiers tell the payer how much of that knee was treated and which side:

• Modifier 52 (reduced services): append it when fewer than the three named branches are destroyed. Physicians use 52 on the professional claim.
• Modifier 74 (facility): hospital and ASC claims may show the same reduced service with 74 instead of 52, per Coding Clinic for HCPCS guidance.
• Modifier 50 (bilateral): report 64624-50 with one unit when both knees are ablated in the same session on a physician claim.
• Modifiers RT and LT: some payers want laterality modifiers on two lines instead of modifier 50. Check the payer’s manual before submission.
• ASC claims: Medicare does not recognize modifier 50 for ASC payment. Report bilateral knees on two lines, or on one line with two units.

Medicare coverage and CPT 64624 reimbursement rates

Medicare Part B covers CPT 64624 when the Medicare Administrative Contractor’s coverage policy is met and the record documents medical necessity. There is no national coverage determination, so the criteria come from each MAC’s local coverage determination (LCD). Check yours in the CMS Medicare Coverage Database before you assume coverage.

The 2026 national averages below come from the Medtronic 2026 RFA coding and payment guide, which reproduces the CY 2026 Medicare fee schedules. Your local rate depends on geographic adjustment, so confirm it in the CMS Physician Fee Schedule look-up tool.

Commercial rates are set by contract and usually differ from Medicare. Bilateral and reduced-service claims pay differently, so price them from the payer’s own rules.

Prior authorization requirements for CPT 64624

Most commercial payers and many Medicare Advantage plans require prior authorization for CPT 64624. Traditional Medicare Part B does not require it, but MAC coverage policies set documentation criteria the claim must meet.

A complete authorization request for 64624 typically includes:

• ICD-10 diagnosis codes establishing knee osteoarthritis, such as M17.11, M17.12, M17.31 or M17.32
• Documentation that conservative treatment failed, such as physical therapy, NSAIDs or joint injections, over the period the plan defines
• Imaging evidence of degenerative knee disease, such as an X-ray or MRI
• Results of a diagnostic genicular nerve block, usually 64454, showing the pain relief the plan requires
• Physician attestation of medical necessity and the planned destruction method

A missing authorization is one of the most frequent denial reasons for this code. A corrected claim with the authorization number can still be paid, but it adds weeks to the payment cycle.

Cryoneurolysis and CPT 64624: What Medicare says

Cryoneurolysis should not be billed to Medicare as 64624 in Noridian’s jurisdictions. Noridian’s Billing and Coding: Cryoneurolysis Instructions (A59752) says CPT 64624 and 64640 require destruction of the target nerve. It finds the iovera system temporary and not destructive, so neither code is appropriate.

Noridian instead directs iovera treatment at the knee to Category III code 0441T and reviews those claims case by case. The article covers Noridian’s JE and JF jurisdictions. A59752 now carries the JF guidance that sat in the retired article A59753, which ended on September 25, 2025.

• Radiofrequency ablation: reported as 64624 when the MAC’s coverage criteria are met.
• Chemical neurolysis: reported as 64624 when the agent destroys the genicular branches and the note documents it.
• Cryoneurolysis (iovera): reported as 0441T under Noridian. Check how your own MAC and commercial payers want it billed before you schedule.

Practices that offer both ablation and cryoneurolysis should keep separate authorization workflows for each. An authorization obtained for radiofrequency ablation does not cover a cryoneurolysis session, and switching the method afterward creates a compliance risk.

Documentation requirements to support CPT code 64624

An operative note that passes payer review for CPT 64624 must go well beyond “performed RFA of the knee.” Auditors look for detail at the level of each nerve branch, not just the joint. Every note needs these elements:

• Named branches: list each branch destroyed by name: superolateral, superomedial and inferomedial genicular nerve. A note that only says “genicular nerves” cannot support a full unit, and fewer than three branches needs modifier 52.
• Laterality: state left, right or bilateral explicitly. Missing laterality triggers modifier denials.
• Method and parameters: state whether conventional RFA, cooled RFA or chemical neurolysis was used. Record the device and the temperature, duration or agent.
• Imaging guidance: record whether fluoroscopy or ultrasound was used. It supports medical necessity but is not billed separately.
• Diagnostic block result: reference the earlier genicular block and the pain relief it produced.
• Outcome and tolerance: add a line or two on the patient’s status after the procedure. Auditors flag notes that stop at the lesion.

A procedure note template built around these elements prevents the vague-documentation denial before it starts. Clean claim submission depends on a note that captures every billable detail at the time of service.

ICD-10 codes paired with CPT 64624

The diagnosis code on the claim establishes medical necessity for 64624. A code missing from the MAC’s covered diagnosis list leads to a denial even when the procedure was clinically appropriate.

Confirm that the chosen code appears on the covered diagnosis list for your MAC’s genicular nerve policy. The covered list sits in the billing and coding article attached to each LCD. On a bilateral 64624-50 claim, M17.0 is the matching diagnosis when both knees have primary osteoarthritis.

Common denial reasons for CPT 64624 and how to prevent them

Genicular ablation claims are denied for a small set of repeat reasons. Coverage criteria differ between MACs, so payers apply them unevenly. These are the seven patterns practices see most often.

Denial management workflows that route each CARC and RARC denial code to the right follow-up action shorten resolution time for 64624 denials. Practices with a high ablation volume benefit from a dedicated denial queue for this code.

How Pabau supports accurate CPT 64624 billing

Most 64624 denials start in the note or the claim build, not at code selection. Pabau, the practice management and billing platform we build, puts the code’s rules into the clinical workflow so errors are caught before the claim leaves.

For 64624, four capabilities matter most:

• Procedure note templates: they prompt for each named branch, the side, the method and the imaging used.
• Superbill configuration: it pairs 64624 with covered knee diagnoses and leaves guidance codes off.
• Claims management software: it links each prior authorization number to its claim and tracks status through payment.
• Clearinghouse connection: Pabau’s Claim.MD integration scrubs each 837P claim against payer edits before submission. Eligibility checks and 835 remittance posting run through the same connection, which cuts manual reconciliation for high-volume ablation practices.

Denial reports filtered by CPT code show whether 64624 denials cluster around one payer, provider or missing note element. A quarterly review lets the billing team fix the pattern before the next batch goes out.

Bill CPT 64624 right the first time

Pabau links procedure notes, scheduling and claims in one platform. Build each 64624 claim from the note, track prior authorization before the procedure and submit through Claim.MD.

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Conclusion

CPT 64624 is one code for one knee, with three named branches and imaging already included. Most billing errors on it come from older coding habits: an add-on unit for each nerve, a separate guidance line, or cryoneurolysis billed as destruction. Strip those habits out of your charge templates first, because they cause the most avoidable denials.

Then check coverage before the procedure is booked. Your MAC’s policy and the patient’s plan decide whether the claim pays, and Noridian has already ruled out 64624 for iovera.

Book a demo to see how Pabau builds each 64624 claim from the procedure note and checks it before it reaches the payer.

Continue your research

Want to understand how electronic remittance advice fits into your revenue cycle? Electronic remittance advice (ERA) explains how 835 files map payment data back to submitted claims.

Looking to verify patient eligibility before RFA procedures? Insurance eligibility verification outlines how real-time eligibility checks prevent coverage surprises on the day of service.

Getting 64624 authorized before the procedure? Prior authorization process walks through each step from request to approval.

Frequently asked questions