Open treatment of a nasomaxillary fracture with internal fixation, requiring surgical exposure and hardware placement to stabilize the fractured nasal and maxillary structures.

Verified May 8, 2026 · 6 sources ↓

Medicare: $913.85
Total RVUs: 27.36
Global, days: 90
Region: Other

Drawn from CMSAAOS

Documentation requirements

What must appear in the operative or office note to support the claim.

Source · Editorial brief grounded in 6 cited references ↓

Operative note must name the specific approach used — do not write 'standard approach'
Document fracture pattern, displacement, and instability that necessitate open treatment with fixation
Identify all hardware placed (plate type, screw count, size) and fixation points
Confirm pre-op imaging findings (CT preferred) correlate with intraoperative fracture characterization
Record any complicating factors that increased operative time or difficulty, especially if modifier 22 is considered
If bilateral involvement, document each side separately with laterality clearly noted

Applicable modifiers

Modifiers commonly billed with this code.

Source · AMA CPT modifier descriptors · CMS NCCI Policy Manual

22 Increased complexity 24 Unrelated E/M during global 25 Significant separate E/M 50 Bilateral procedure 51 Multiple procedures 52 Reduced services 57 Decision for surgery 58 Staged or related 59 Distinct service 76 Repeat, same physician 77 Repeat, another physician 78 Unplanned return — related 79 Unrelated during global 80 Assistant surgeon LT Left side RT Right side

What this code covers

Source · Editorial summary grounded in 6 cited references ↓

CPT 21346 covers open surgical treatment of a nasomaxillary fracture with fixation — meaning the surgeon makes an incision, directly visualizes the fracture site, reduces the fragments, and secures them with hardware such as plates or screws. This is a distinct step up from closed or percutaneous approaches and is used when fracture displacement, instability, or complexity demands rigid internal fixation for proper healing and facial contour restoration.

The code carries a 90-day global period. That window includes the day-before and day-of preoperative evaluation, the procedure itself, and all routine postoperative care through day 90. E/M visits during that period billed for unrelated conditions require modifier 24. If the decision for surgery was made at the same visit as the procedure, append modifier 57 to that E/M code. Staged or planned return procedures by the same surgeon use modifier 58; an unplanned return to the OR for a related complication uses modifier 78.

Note that CMS removed 21346 from its Device Procedure list effective January 1, 2021, and adjacent codes for nasomaxillary fractures with grafting (21348) and multiple-fragment variants (21347) were removed from HOPD device-procedure tracking lists effective January 1, 2022. Verify current NCCI edits before billing 21346 alongside ancillary craniofacial codes, as bundling rules in the facial fracture code family are frequently audited.

RVU & reimbursement

Component RVUs and Medicare national rate. Actual payment varies by GPCI locality.

Source · CMS Physician Fee Schedule, RVU26A · January 2026

Work RVU	11.16
Practice expense RVU	14.57
Malpractice RVU	1.63
Total RVU	27.36
Medicare national rate	$913.85
Global period	90 days

Payment by site of service

Medicare pays different rates by setting. HOPD typically pays substantially more than ASC for the same procedure.

Source · CMS OPPS Addendum B·ASC HCPCS payment rates·2026

Setting	Medicare rate (national)
Office (PFS non-facility) Procedure performed in physician's office	$913.85
HOPD (APC 5165) Hospital outpatient department	$6,048.05
ASC (PI G2) Ambulatory surgical center (freestanding)	$3,025.62

Common denial reasons

The recurring reasons claims for CPT 21346 get rejected.

Source · Editorial brief grounded in CMS NCCI edits, AAOS coding appeals, and cited references ↓

Operative note lacks documentation of why open treatment with fixation was required over closed reduction
Missing or inadequate pre-operative imaging corroborating fracture severity
E/M billed during the 90-day global period without modifier 24 for an unrelated condition
Incorrect modifier sequencing when billing a same-day E/M with the surgical decision — modifier 57 omitted
NCCI bundling conflict with simultaneously billed adjacent craniofacial or sinus fracture codes

Frequently asked questions

Source · Generated from the editorial pipeline, verified against 6 cited references ↓

01What distinguishes 21346 from 21343 or 21344?

21346 is specific to the nasomaxillary complex with fixation. 21343 and 21344 address depressed frontal sinus fractures — a different anatomical region. Do not substitute codes across facial fracture sub-regions even when the surgical approach overlaps.

02Can 21346 and 21347 be billed together for a complex multi-fragment nasomaxillary fracture?

21347 (multiple nasomaxillary fragments, open) was removed from HOPD device procedure lists effective 2022 and must be checked against current NCCI edits before billing alongside 21346. Bundling rules in craniofacial fracture codes are actively enforced — run an NCCI check before submitting both.

03Is modifier 50 appropriate if both sides of the nasomaxillary complex are treated?

If the fracture is truly bilateral and both sides are addressed in the same operative session, modifier 50 is the correct approach. Document each side's fracture pattern and fixation separately in the operative note.

04What does the 90-day global period cover for 21346?

The 90-day global includes the day-before preoperative visit, the procedure, and all routine post-op care through day 90 — wound checks, suture removal, and standard follow-up. Bill unrelated E/M visits in that window with modifier 24; use modifier 57 if the surgery decision was made at the pre-op visit.

05When is modifier 22 justified for 21346?

Modifier 22 applies when operative work is substantially greater than typical — for example, severe comminution, prior surgical scarring complicating exposure, or significantly extended operative time. The operative note must quantify the additional work; auditors reject modifier 22 claims backed only by a generic statement that the case was 'complex.'

06Was 21346 removed from any CMS lists and does that affect billing?

Yes — CMS removed 21346 from its Device Procedure list effective January 1, 2021 (per CMS Claims Processing transmittal). This affects HOPD device-procedure payment tracking but does not eliminate the code for professional or facility billing. Confirm current payer-specific coverage policies before submitting.

Sources & references

Editorial content was developed using the following public sources. Last verified May 8, 2026.

Mira AI Scribe

Mira's AI scribe captures the fracture pattern, degree of displacement, surgical approach by name, all hardware placed (plate type, screw dimensions, fixation points), and the clinical rationale for open fixation over closed reduction — directly from dictation. That documentation prevents the leading denial trigger for 21346: an operative note that confirms hardware was used but fails to justify why open treatment was medically necessary.

See how Mira captures CPT 21346 documentation