Surgical · Other

Forehead reduction involving contouring plus surgical setback of the anterior frontal sinus wall

Verified May 8, 2026 · 6 sources ↓

Medicare: $984.32
Work RVU: 14.64
Global, days: 90
Region: Other

Drawn from CMSAmidacarenyHiacode

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 explicitly describe removal, contouring, and setback of the anterior frontal sinus wall — not just surface bur-down or shaving
Distinguish clearly from 21137 (contouring only) and 21138 (contouring with prosthetic); the note must confirm sinus wall osteotomy and repositioning occurred
ICD-10 diagnosis code must support medical necessity — document whether indication is gender dysphoria, post-traumatic deformity, oncologic reconstruction, or congenital anomaly
Preoperative imaging (CT scan of frontal sinus anatomy) referenced in the operative note strengthens medical necessity and establishes surgical complexity
If modifier 22 is appended, a separate written justification of substantially increased intraoperative time or complexity must accompany the claim
Document any concurrent procedures (e.g., 21172 orbital contouring, 15824 browlift) with distinct procedural descriptions to support unbundling with modifier 59 where applicable

Applicable modifiers

Modifiers commonly billed with this code.

Source · AMA CPT modifier descriptors · CMS NCCI Policy Manual

22 Increased complexity 51 Multiple procedures 52 Reduced services 59 Distinct service 62 Co-surgeons 76 Repeat, same physician 77 Repeat, another physician 78 Unplanned return — related 79 Unrelated during global 24 Unrelated E/M during global 25 Significant separate E/M

What this code covers

Source · Editorial summary grounded in 6 cited references ↓

CPT 21139 covers forehead reduction that goes beyond surface contouring — the anterior wall of the frontal sinus is removed, reshaped, and set back before being repositioned. This distinguishes it from 21137 (contouring/shaving only) and 21138 (contouring with prosthetic replacement of the sinus wall). When the operative note describes frontal sinus wall osteotomy and repositioning, 21139 is the correct code; using 21137 instead understates the work and leaves RVUs on the table.

The 90-day global period means all routine post-op visits, wound checks, and suture removals through day 90 are bundled. Separate E/M services during that window require modifier 24 (unrelated evaluation) or 25 (same-day significant, separately identifiable visit). New or worsening complications managed in the OR during the global period use modifier 78 for related returns or 79 for unrelated procedures.

This code appears frequently in facial feminization surgery (FFS) contexts and in craniofacial reconstruction after trauma or oncologic resection. Payer coverage varies sharply: commercial plans may cover it as reconstructive, while others classify it cosmetic. Medicare coverage is governed by local LCD policy. Always confirm the ICD-10 diagnosis code supports medical necessity before submitting — gender dysphoria (F64.0), traumatic deformity, or post-oncologic reconstruction diagnoses carry different coverage pathways across payers.

RVU & reimbursement

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

Source · CMS Physician Fee Schedule, RVU26A · January 2026

Work RVU vs. total RVU

The work RVU (14.64) is the surgeon's own effort — the figure physician pay and productivity targets are built on. The total RVU (29.47) adds practice overhead and malpractice, and is what drives the Medicare payment below.

Work RVU	14.64
Practice expense RVU	12.11
Malpractice RVU	2.72
Total RVU	29.47
Medicare national rate	$984.32
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	$984.32
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 21139 get rejected.

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

Cosmetic exclusion — payer classifies the procedure as aesthetic rather than reconstructive without adequate medical necessity documentation tied to the diagnosis
Wrong code billed — 21137 submitted when operative note describes frontal sinus wall setback, resulting in downcoded reimbursement or mismatch denial
Global period conflict — post-op E/M or minor procedure submitted without modifier 24, 25, 78, or 79 during the 90-day global window
NCCI bundling — concurrent facial procedures (e.g., orbital contouring, rhinoplasty) billed same-day without modifier 59 or XS to establish distinct procedural services
Missing prior authorization — many payers require pre-auth for craniofacial osteotomy procedures; claims submitted without an auth number deny on intake

Frequently asked questions

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

01What is the difference between CPT 21137, 21138, and 21139?

21137 is forehead contouring by shaving or burring only — no sinus work. 21138 adds a prosthetic implant to replace the sinus wall. 21139 involves removing, recontouring, and surgically setting back the actual anterior frontal sinus wall. Bill based on what was documented in the operative note, not the diagnosis.

02Can 21139 and 21137 both be billed on the same date?

No. Per coding guidance for facial feminization surgery, 21137 and 21139 are mutually exclusive on the same operative session. If sinus setback was performed, report 21139 only.

03Is 21139 covered by Medicare?

Coverage depends on the indication. Medicare follows local LCD policy for cosmetic and reconstructive surgery. Procedures tied to trauma repair, oncologic reconstruction, or gender dysphoria (with appropriate supporting documentation) may meet coverage criteria. Purely aesthetic cases typically do not.

04What modifier applies if the surgeon returns to the OR during the 90-day global for a related complication?

Use modifier 78 — unplanned return to the OR for a related procedure during the postoperative period. Modifier 79 is for unrelated procedures during the global. Do not invert these.

05Does 21139 require prior authorization?

Most commercial payers require prior authorization for craniofacial osteotomy procedures. Submit the auth request with imaging, operative plan, and the supporting diagnosis. Claims submitted without a valid auth number routinely deny on intake regardless of medical necessity.

06Can 21139 be billed alongside orbital contouring (21172) or browlift (15824)?

These can be reported together when performed as distinct procedures with separate operative descriptions. Check NCCI edits for bundling conflicts and append modifier 59 or XS where required to establish that each service was independent.

Sources & references

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

Mira Scribe

Mira's AI scribe captures the specific surgical steps from dictation — frontal sinus wall osteotomy, degree of setback, method of fixation, and any concurrent facial procedures — and flags when the note describes sinus wall repositioning but the coded procedure is 21137. That prevents the most common undercoding error on this case type. The scribe also tags the primary diagnosis code against the procedure so cosmetic-vs-reconstructive ambiguity is resolved at the note level, not at the clearinghouse.

See how Mira captures CPT 21139 documentation