CPT 21423Surgery

Optx palatal/max fx comp

CPT code 21423 covers the surgical repair of complex fractures of the palate (roof of the mouth) or upper jaw bone (maxilla). This is an intricate procedure requiring open surgical treatment to realign and stabilize broken facial bones.

Showing rates for

National Average

Base Medicare rate

$778.90

This calculator gives a typical-case estimate using standard Medicare modifier rules. Actual payment depends on payer policies, documentation, code-specific CMS status indicators, and locality. Verify before billing.

RVU breakdown

Work RVU

10.85

PE RVU (NF)

11.25

MP RVU

1.98

Total RVU

24.08

Conversion factor: 32.3465 · Source: CMS MPFS RVU25A · Confidence: High

NCCI bundling edits

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Billing tips

Document fracture complexity thoroughly in operative report including number of fracture lines, degree of displacement (in mm), comminution, and number/type of fixation devices used
Impact: Supports medical necessity and justifies the complex designation; prevents downcoding to simpler fracture codes (21421) which reimburse $200-300 less
Verify facility vs. non-facility setting designation as both rates are identical at $778.90 for 21423, but ensure place of service code matches actual location
Impact: Prevents automatic denials for POS/rate mismatches; ensures proper claims processing without delays
When billing with modifier 22, include a detailed cover letter quantifying additional time (typically 50%+ beyond usual), unusual anatomical findings, or patient complexity with specific intraoperative details
Impact: Increases approval rate for modifier 22 from approximately 30% to 70%; can add $155-$235 to base reimbursement when properly documented
Separately report CT scan interpretation (70486-70488) when personally reviewing preoperative imaging for surgical planning; do not bundle into surgical code
Impact: Additional $50-150 revenue per case when appropriately documented and dictated as separate professional service
Bill concurrent procedures (nasal fracture repair 21338-21339, orbital fracture repair 21385-21395) with appropriate sequencing and modifiers 51/59 when distinct anatomical sites are addressed
Impact: Secondary procedures receive 50% reimbursement; failing to report can result in $300-500 lost revenue per case on panfacial trauma
Ensure anesthesia provider uses correct ASA code (00192 for radical surgery involving skull, face and mouth) and document medical necessity for general anesthesia vs. sedation

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Frequently asked questions

What is the Medicare reimbursement rate for CPT 21423 in 2025?

The 2025 Medicare national average reimbursement for CPT 21423 is $778.90 for both facility and non-facility settings. This rate is based on 24.08 total RVUs (10.85 work RVU + 11.25 practice expense RVU + 1.98 malpractice RVU) multiplied by the 2025 conversion factor of 32.3465.

What is the difference between CPT 21423 and 21421?

CPT 21421 covers open treatment of simple palatal or maxillary fractures with minimal complexity, while 21423 is for complicated fractures requiring extensive reconstruction. Complicated fractures (21423) typically involve multiple fracture lines, significant displacement, comminution, or involvement of multiple maxillary segments requiring more extensive fixation and longer operative time.

Can CPT 21423 be billed bilaterally with modifier 50?

No, CPT 21423 is not designated as a bilateral procedure because maxillary/palatal fractures typically involve midline or multiple segments as a single complex injury. Use modifiers LT/RT only when documenting lateralization of the specific fracture site, but do not expect bilateral payment increase. If truly bilateral separate fractures exist, document thoroughly and consider modifier 22 for increased complexity.

What documentation is required to justify modifier 22 with CPT 21423?

For modifier 22, document operative time at least 50% longer than typical (usually 90+ minutes for 21423), extensive comminution requiring multiple fixation points, unusual anatomical challenges, severe patient comorbidities affecting surgical approach, or pediatric cases with developing dentition requiring specialized techniques. Include quantifiable metrics like number of plates/screws used and specific anatomical challenges overcome.

How long is the global period for CPT 21423?

CPT 21423 has a 90-day global surgical period. This includes preoperative evaluation on day of or day before surgery, the operative procedure, and all routine postoperative care for 90 days. Any return to OR for complications during this period requires modifier 78, while unrelated procedures require modifier 79 to bypass the global period.

Can I bill CPT 21423 with nasal fracture repair codes?

Yes, you can bill CPT 21423 with nasal fracture repair codes (21338-21339) when both procedures are performed and the fractures are distinct anatomical injuries. Apply modifier 59 or XS to the secondary procedure to indicate separate anatomical site. Ensure documentation clearly describes both the maxillary/palatal fracture and the separate nasal bone fracture with distinct reduction and fixation techniques.

What specialties typically bill CPT code 21423?

CPT 21423 is primarily billed by oral and maxillofacial surgeons (OMFS), followed by plastic surgeons with craniofacial subspecialty training, otolaryngologists specializing in facial trauma, and trauma surgeons at centers managing complex facial injuries. The provider must have hospital privileges for open facial fracture repair and the procedure is typically performed under general anesthesia in hospital or ASC settings.