Surgical · Other

Midface reconstruction using osteotomies that are not LeFort-type, with bone grafting including harvesting of autograft bone.

Verified May 8, 2026 · 6 sources ↓

Medicare: $1,428.89
Total RVUs: 42.78
Global, days: 90
Region: Other

Drawn from CMSAAOSLouisianahealthconnectJnjmedtech

Documentation requirements

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

Source · Editorial brief grounded in 6 cited references ↓

Specify that osteotomies performed are non-LeFort type — document why LeFort classification does not apply to this anatomy.
Describe the autograft harvest site, volume, and technique; harvesting is bundled and must appear in the operative note.
Document the functional impairment driving surgical necessity (e.g., mastication difficulty, airway obstruction with PSG data, documented skeletal deformity measurements).
Include preoperative imaging (CT with measurements) demonstrating the bony deformity and planned osteotomy sites.
Record the specific osteotomy approach and segmental movements performed intraoperatively.
If modifier 22 is applied, the operative note must articulate the specific factors that made the work substantially greater than typical — altered anatomy, adhesions, prior surgery, or prolonged operative time with explanation.

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 57 Decision for surgery 58 Staged or related 59 Distinct service 62 Co-surgeons 76 Repeat, same physician 77 Repeat, another physician 78 Unplanned return — related 79 Unrelated during global 80 Assistant surgeon

What this code covers

Source · Editorial summary grounded in 6 cited references ↓

CPT 21188 covers midface reconstruction performed through osteotomies that fall outside the LeFort classification system (LeFort I, II, and III are reported separately under 21145–21160). The procedure includes obtaining and placing autogenous bone grafts — harvesting is bundled into the code and not separately billable. Typical indications include congenital midface deformities, post-traumatic deformities, fibrous dysplasia, and craniofacial syndromes where the anatomy doesn't conform to a standard LeFort pattern.

This is a high-complexity craniofacial procedure with a 90-day global period. All routine post-op care through day 90 is bundled. If a staged procedure was planned at the time of the initial surgery, use modifier 58 on the return case — it resets the global clock. Unplanned returns to the OR for a related complication take modifier 78; unrelated procedures in the global window take modifier 79.

Payers — particularly commercial carriers — treat 21188 as medically necessary only when documented functional impairment is present (masticatory dysfunction, airway obstruction, speech impairment, or documented skeletal deformity meeting quantified thresholds). Cosmetic intent is a hard denial. Prior authorization is almost universally required by commercial and Medicaid 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	22.57
Practice expense RVU	16.94
Malpractice RVU	3.27
Total RVU	42.78
Medicare national rate	$1,428.89
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	$1,428.89
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 21188 get rejected.

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

Cosmetic intent — payer determines no documented functional impairment; prior auth not obtained or authorization criteria not met.
Wrong code selection — LeFort-type osteotomies billed under 21188 instead of the specific LeFort codes (21145–21160); auditors flag the mismatch against operative note.
Autograft harvest billed separately (e.g., as a bone graft procurement code) when it is already bundled into 21188.
Missing or insufficient prior authorization — most commercial and Medicaid payers require auth for orthognathic/craniofacial reconstruction; claims denied on missing auth.
Global period conflict — post-op E/M billed without modifier 24 during the 90-day global window.

Frequently asked questions

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

01How do I know whether to use 21188 versus one of the LeFort codes like 21145 or 21154?

If the osteotomy pattern fits a recognized LeFort I, II, or III classification, use the corresponding LeFort code (21145–21160). Use 21188 only when the osteotomy approach is distinct from any LeFort pattern — document explicitly in the operative note why LeFort classification does not apply.

02Can I bill separately for autograft harvesting with 21188?

No. Obtaining the autograft is bundled into 21188. Billing a separate graft procurement code will be denied via NCCI edits.

03What modifier applies if I planned a staged second surgery at the time of the initial 21188?

Use modifier 58 on the second procedure. Document the staged intent in the initial operative note. Modifier 58 resets the global period clock for the second case.

04Is prior authorization required for 21188?

Nearly universally, yes — for commercial payers and most Medicaid plans. Criteria typically require documented skeletal deformity measurements and a functional impairment (mastication, airway, speech). Obtain auth before scheduling and retain the clinical documentation used to support the request.

05Can modifier 22 be used if the reconstruction was significantly more complex than usual?

Yes, but the operative note must specifically describe what made the work substantially greater — prior surgery creating scarring, severely distorted anatomy, unexpected intraoperative findings, or significantly prolonged time with explanation. A generic statement of complexity is insufficient; auditors require concrete detail.

06What is the global period for 21188, and what does it include?

21188 carries a 90-day global period. Routine post-op visits, dressing changes, and stitch removal within that window are bundled. Bill E/M services during the global period only for unrelated problems (modifier 24) or if the visit represented the decision for surgery (modifier 57 applies to the pre-op E/M).

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 osteotomy type and confirms non-LeFort classification, the autograft harvest site and technique, segmental movement direction and distance, and the functional diagnosis driving the case. This prevents the most common audit flag — an operative note that describes the procedure without explicitly excluding LeFort anatomy, which reviewers use to challenge code selection and deny as upcoded or cosmetically motivated.

See how Mira captures CPT 21188 documentation