Open treatment of a craniofacial separation fracture — the most complex category — requiring multiple internal fixation points and, when needed, bone grafting across the cranial-facial junction.
Verified May 8, 2026 · 5 sources ↓
- Medicare
- $1,804.65
- Total RVUs
- 54.03
- Global, days
- 90
- Region
- Other
Documentation requirements
What must appear in the operative or office note to support the claim.
Source · Editorial brief grounded in 5 cited references ↓
- Mechanism and severity of trauma explicitly documented — high-energy mechanism supports medical necessity for the complex code level
- Operative note must name the specific fracture pattern (e.g., Le Fort III, panfacial, craniofacial disjunction) — 'complex facial fracture' alone is insufficient
- All incision sites described individually; 'multiple approaches' without anatomic detail flags for audit
- Internal fixation method and location documented for each fixation point — number and placement support the 'multiple' descriptor
- Bone graft use documented with source (autograft vs. allograft) and graft site if autologous harvest is performed separately
- If co-surgeon arrangement: both operative notes must reflect each surgeon's distinct, documented role
Applicable modifiers
Modifiers commonly billed with this code.
Source · AMA CPT modifier descriptors · CMS NCCI Policy Manual
What this code covers
Source · Editorial summary grounded in 5 cited references ↓
CPT 21436 covers open surgical repair of a complex craniofacial separation (Le Fort III equivalent or higher complexity), accessed through multiple incisions to expose the fracture line where the facial skeleton has separated from the cranial base. The surgeon reduces the fracture, applies internal fixation hardware at multiple points, and typically incorporates bone graft material to restore structural continuity. This is the apex of the craniofacial fracture code family — more extensive than 21435 — and is reserved for cases involving severe midfacial disruption following high-energy trauma.
The 090-day global period governs all post-op care. Separately billing routine fracture follow-up within that window will be denied; modifier 24 applies only if the visit addresses a genuinely unrelated problem. Complications managed operatively after the index surgery require modifier 78 (related return) or 79 (unrelated return) — not interchangeably.
These cases nearly always involve craniofacial or plastic surgery teams in an inpatient or high-acuity outpatient setting. When a second surgeon participates and both meet co-surgeon criteria, modifier 62 applies to each surgeon's claim. If an assistant surgeon is used instead, modifier 80 or AS (for non-physician practitioners) is appropriate. Confirm co-surgery allowance with the payer before billing — not all carriers reimburse 62 on this code at full rates.
RVU & reimbursement
Component RVUs and Medicare national rate. Actual payment varies by GPCI locality.
Source · CMS Physician Fee Schedule, RVU26A · January 2026
| Work RVU | 29.54 |
| Practice expense RVU | 19 |
| Malpractice RVU | 5.49 |
| Total RVU | 54.03 |
| Medicare national rate | $1,804.65 |
| 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 | $1,804.65 |
HOPD (APC 5165) Hospital outpatient department | $6,048.05 |
ASC (PI J8) Ambulatory surgical center (freestanding) | $3,833.49 |
Common denial reasons
The recurring reasons claims for CPT 21436 get rejected.
Source · Editorial brief grounded in CMS NCCI edits, AAOS coding appeals, and cited references ↓
- Upcoding from 21435 without documentation of multiple internal fixation sites — payers default to the lower complexity code when the note is ambiguous
- Bundling conflict when bone graft harvest (e.g., calvaria or iliac crest) is billed separately without modifier 59/XS distinguishing it as a distinct service
- Modifier 62 rejected because one surgeon's note does not independently document a distinct surgical role
- Routine post-op visit billed within the 90-day global without modifier 24, resulting in automatic denial
- Missing or generic fracture pattern designation in the diagnosis — ICD-10 specificity required to match claim complexity level
Frequently asked questions
Source · Generated from the editorial pipeline, verified against 5 cited references ↓
01What separates 21436 from 21435?
02Can I bill a separate code for bone graft harvest when performing 21436?
03How does the 90-day global affect trauma follow-up visits?
04When is modifier 62 appropriate on 21436?
05Is 21436 payable in an ASC setting?
06What ICD-10 codes are typically paired with 21436?
Sources & references
Editorial content was developed using the following public sources. Last verified May 8, 2026.
- 01CMS Physician Fee Schedule 2026
- 02aapc.comhttps://www.aapc.com/codes/cpt-codes/21436
- 03cms.govhttps://www.cms.gov/files/document/medicare-ncci-policy-manual-2024-chapter-4.pdf
- 04aaos.orghttps://www.aaos.org/quality/coding-and-reimbursement/
- 05aoassn.orghttps://www.aoassn.org/wp-content/uploads/2020/12/CodingTTP.pdf
Mira AI Scribe
Mira's AI scribe captures the fracture pattern by name, each incision approach with anatomic location, the number and placement of fixation points, and graft source when applicable — directly from dictation. That prevents the single most common downcode on 21436: an operative note that describes a complex repair without documenting the specific elements that distinguish it from 21435.
See how Mira captures CPT 21436 documentation