CPT code 23120 – Open partial claviculectomy

Key takeaways

CPT code 23120 covers open partial claviculectomy only. Total removal is 23125, and the arthroscopic version is 29824.

CMS gives 23120 a 90-day global period, so routine post-op visits in that window are bundled into the surgical payment.

The 2026 national Medicare payment is about $565 in both facility and office settings, because the total RVU is 16.91 either way.

When 23120 shares a session with 29827, list 29827 first and add modifier 51 to 23120 only if the payer asks for it.

Pabau’s claims management software sends claims electronically through Claim.MD and returns eligibility checks and ERAs to the practice.

CPT code 23120 covers open partial claviculectomy only

CPT code 23120 describes the open surgical removal of part of the clavicle, most often the distal end at the acromioclavicular (AC) joint.

The American Medical Association, which maintains the CPT code set, publishes the descriptor as Claviculectomy; partial. Removal of the whole bone is a different code, 23125.

Clinically, the procedure removes enough distal clavicle to stop bone-on-bone contact at the AC joint. The open Mumford procedure is the classic example. The surgeon makes a direct incision, excises 1 to 2 centimeters of the distal clavicle, and closes the wound. The arthroscopic Mumford uses portals instead and is coded as 29824.

Clinical indications payers expect to see

Payers want the operative record to establish medical necessity. Common indications that support a 23120 claim include:

• AC joint osteoarthritis (ICD-10-CM M19.011/M19.012 for primary osteoarthritis of the shoulder)
• Distal clavicle osteolysis (M89.511/M89.512), seen often in weightlifters and overhead athletes
• Post-traumatic AC arthritis following a prior separation or fracture
• Acromioclavicular joint impingement that hasn’t responded to conservative care
• Failed prior acromioplasty with lingering AC joint symptoms

Each indication has to appear in both the clinical notes and the operative report. When the pre-operative diagnosis and the operative findings disagree, auditors notice, and orthopedic claims draw extra review.

What 23120 bundles and what you can bill separately

Knowing the code’s scope prevents two opposite errors. One is unbundling services already included. The other is leaving legitimately distinct work unbilled.

The National Correct Coding Initiative (NCCI) publishes quarterly edit tables that define which procedure pairs bundle. Check the current version before billing 23120 alongside any arthroscopic shoulder code. A pair that was separately reportable in Q1 may bundle by Q3.

CPT 23120 vs 29824: The incision decides the code

The surgical approach controls which code applies. Mixing up 23120 with 29824, the arthroscopic distal claviculectomy, is a common error on AC joint claims. Code 29826 sometimes gets pulled into the same decision, but it is an add-on for subacromial decompression, not a clavicle code.

Sometimes a surgeon starts arthroscopically and converts to open in the same session. Document the conversion in the operative note and report only the open code, 23120. Never bill both codes for one converted case.

Here’s the whole decision on one screen:

Diagnosis codes that prove medical necessity for 23120

The ICD-10-CM code establishes medical necessity and decides whether the claim meets the Local Coverage Determination (LCD). Each Medicare Administrative Contractor (MAC) may publish its own list of covered shoulder diagnoses.

The codes below are commonly accepted, but check the applicable LCD before you submit.

Laterality is mandatory. Submitting M19.01 without the sixth character for right (1) or left (2) returns an invalid-code rejection before anyone reviews the claim. Specify the operative side in every field.

Medicare pays about $565 for CPT code 23120 in 2026

Medicare reimbursement for CPT code 23120 comes from the annual CMS Physician Fee Schedule. The 2026 national figure is about $565, using the $33.4009 conversion factor. Facility and office payments match because the total RVU is 16.91 in both settings.

Use the FastRVU RVU lookup or the CMS search tool to pull the work, practice expense, and malpractice RVUs for your locality. Geographic practice cost indices (GPCIs) then adjust the national figure up or down, so rural and high-cost urban practices see different payments.

The 90-day global period for CPT 23120

CPT code 23120 carries a 90-day global surgical period under CMS. During that window, the operating surgeon can’t separately bill these services:

• Pre-operative evaluation the day before or day of surgery
• Routine post-operative E&M visits related to the surgical procedure
• Minor procedures (injections, suture removal) related to the surgery
• Pain management directly related to the surgical site

Some services inside the window stay billable. Unrelated E&M visits take modifier 24, new conditions needing distinct treatment take modifier 79, and staged procedures take modifier 58. Spell out the clinical distinction in the encounter note.

Modifiers for CPT code 23120 depend on what else you billed

Modifier choice for CPT code 23120 turns on two questions. Did the surgeon perform other procedures in the same session, and what does the payer’s NCCI edit require? A wrong or missing modifier is a frequent denial trigger.

The AAPC Codify CPT lookup shows modifier guidance and NCCI edit status for 23120. NCCI edits update quarterly, so check the edit table in effect on the date of service, not today’s.

Get prior authorization for 23120 before the surgery date

Most commercial payers and Medicare Advantage plans require prior authorization for elective shoulder surgery, claviculectomy included. Requirements vary by payer, but most requests ask for the same core documents:

• Conservative treatment failure: at least six weeks of physical therapy, NSAIDs, or corticosteroid injection, with exact timeframes set by the payer
• Imaging evidence: a shoulder X-ray (CPT 73030) or MRI showing AC joint pathology, osteolysis, or arthrosis
• Clinical notes: office visit records showing symptom duration, functional limitation, and failed conservative care
• ICD-10-CM diagnosis: the same diagnosis code you plan to put on the claim
• Operative plan: the planned procedure, the open approach, and the expected extent of resection

Good medical billing compliance means confirming authorization before the surgery date, not at claim submission. A claim that reaches adjudication without an approved auth comes back as a CO-197 denial, which is hard to fix after the fact.

What the operative report needs to support 23120

Thin operative documentation is a leading reason 23120 claims get denied or downcoded after audit. The report should contain each of these elements before the claim goes out.

• Approach confirmed as open: the report states that an incision was made directly over the AC joint, with no portal placement
• Extent of resection: the amount of clavicle removed in millimeters or centimeters, confirming a partial resection
• Anatomical landmarks: reference to the coracoclavicular ligaments and AC joint capsule confirms the surgeon operated at the right site
• Pre-operative and post-operative diagnosis: both present and consistent with the ICD-10-CM code on the claim
• Implants or fixation: if any hardware was placed (rare in claviculectomy), the implant name and manufacturer lot number
• Complications: if there were none, a plain “no intraoperative complications” line, since post-payment audits sometimes flag its absence

A clean claim submission starts with documentation that is complete before the claim leaves the practice. Operative reports amended after a denial get extra scrutiny from commercial payers and Medicare RAC auditors.

How a 23120 claim moves from op note to payment

Once the report is signed, the claim follows a predictable path. Each step is a place it can stall.

1. The surgeon signs an operative note that confirms the open approach and the resection length.
2. The coder assigns 23120, the ICD-10-CM code with laterality, and any modifiers, then checks NCCI edits for co-billed codes.
3. The professional claim goes to the clearinghouse, which rejects format errors such as a missing laterality character.
4. The payer checks authorization, LCD coverage, and the global period before pricing the claim.
5. An electronic remittance advice (ERA) comes back with the payment or a claim adjustment reason code (CARC).

Common 23120 denials and how to prevent them

23120 claims sit where medical necessity, NCCI bundling, and authorization meet, so several things can go wrong. Each denial reason below maps to one prevention step.

Effective denial management workflows add a pre-claim scrub that checks authorization, NCCI edits, and diagnosis-to-procedure linkage. Reading the medical billing denial codes on each ERA lets billers appeal with the right documents the first time.

Before you submit: A five-point check

• The authorization number is confirmed and on file.
• Every co-billed code has been checked against the current NCCI edit table.
• The LT or RT modifier is on the claim and matches the diagnosis code.
• The diagnosis code appears in the MAC’s LCD for this procedure.
• The operative report is complete, signed, and states the open approach.

Related shoulder codes and how they interact with 23120

Shoulder surgery claims rarely carry a single code. Knowing the neighboring codes protects revenue from separately reportable work and avoids denials for improper unbundling.

When rotator cuff repair (29827) and open claviculectomy happen in the same session, list 29827 first. It carries the higher RVU, so 23120 becomes the secondary procedure and takes modifier 51 where the payer requires it.

Medicare contractors apply the multiple-procedure payment reduction automatically, and many commercial payers do the same. In medical billing, that sequence decides which line is paid at 100% and which is reduced.

How claims management software keeps 23120 claims moving

Many orthopedic practices still key surgical claims into a clearinghouse portal by hand. Then they phone payers to check eligibility and wait days to learn a claim was denied. Every handoff adds a chance to drop a laterality modifier or miss an auth number.

Pabau’s claims management software sends claims electronically through its Claim.MD integration. Eligibility checks run before the surgery date. ERAs post back against the patient record, so a CO-97 or CO-197 shows up the day it lands.

Coding decisions stay with your coders. Pabau doesn’t pick modifiers or apply NCCI edits, but it cuts the retyping and chasing between the op note and the payment.

Send shoulder surgery claims and track every ERA

Pabau submits claims electronically through Claim.MD and posts eligibility and ERA responses back to the patient record. Your team sees a denied 23120 claim the day it lands.

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Conclusion

For 23120, the operative note does most of the coding work. If it states an incision and a partial resection length, the code holds up. If it doesn’t, no modifier will rescue the claim.

So make the op note your first check, then confirm the authorization and NCCI edits before release. The trade-off is a few extra minutes per claim against a 90-day global window you can’t rebill once a denial lands.

Book a demo to see how Pabau gets your shoulder surgery claims to payers faster and flags denials as soon as they post.

Continue your research

Coding the arthroscopic version instead? CPT code 29824 covers distal claviculectomy through the scope, with its own documentation rules.

Adding a subacromial decompression? CPT code 29826 explains how the add-on rides on a primary arthroscopic shoulder code.

Need help managing surgical claim denials systematically? Denial management in healthcare covers the full workflow for tracking, appealing, and preventing claim denials across procedure types.

Want to understand how clearinghouse submission works? Medical claims clearinghouse explains how electronic claims move from the practice to the payer and where errors are caught.

Looking for a compliance framework for orthopedic billing? Medical billing compliance outlines the documentation and audit readiness requirements that protect practices during post-payment review.

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