Surgical reconstruction of the sternum to correct congenital chest wall deformities such as pectus excavatum (sunken chest) or pectus carinatum (protruding chest).

Verified May 8, 2026 · 5 sources ↓

Medicare: $989.67
Work RVU: 17.13
Global, days: 90
Region: Other

Drawn from CMSAAPC

Documentation requirements

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

Source · Editorial brief grounded in 5 cited references ↓

Specify the deformity type (pectus excavatum vs. pectus carinatum) with ICD-10 diagnosis code to establish medical necessity.
Include objective severity measurement, such as Haller index from preoperative CT, for pectus excavatum cases requiring payer authorization.
Name the surgical technique by name (e.g., modified Ravitch, sternal osteotomy with costal cartilage resection) — notes that only say 'standard repair' are audit flags.
Document any internal brace, strut, or implant hardware placed, including type and positioning.
Record operative findings confirming the structural deformity and extent of reconstruction performed.
Note any prior conservative treatment attempts and duration to support medical necessity if payer requires exhaustion of non-surgical options.

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 78 Unplanned return — related 79 Unrelated during global 80 Assistant surgeon AS PA/NP/CNS assistant

What this code covers

Source · Editorial summary grounded in 5 cited references ↓

CPT 21740 covers open reconstruction of the sternum for congenital chest wall deformities. The two primary indications are pectus excavatum — where the sternum is pathologically depressed — and pectus carinatum — where the sternum protrudes abnormally. The procedure involves reshaping or repositioning the sternum and associated costal cartilages to restore normal thoracic architecture. A 90-day global period applies, meaning all routine postoperative care through day 90 is bundled into the surgical payment. Any visit during that window unrelated to the reconstruction requires modifier 24 (E/M) or 79 (unrelated procedure).

This code sits in the neck and thorax repair/reconstruction section of the CPT manual, not the cardiac or thoracic surgery sections, which matters for specialty credentialing and payer authorization pathways. Payers frequently require documented failure of conservative management and objective severity metrics — such as the Haller index on CT for pectus excavatum — before approving surgical authorization. Missing that pre-authorization documentation is the leading reason for denial. Operative notes must specify the surgical technique used (e.g., Ravitch procedure, sternal osteotomy with cartilage resection), hardware or implant placement if applicable, and the specific deformity corrected.

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 (17.13) is the surgeon's own effort — the figure physician pay and productivity targets are built on. The total RVU (29.63) adds practice overhead and malpractice, and is what drives the Medicare payment below.

Work RVU	17.13
Practice expense RVU	8.19
Malpractice RVU	4.31
Total RVU	29.63
Medicare national rate	$989.67
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	$989.67
HOPD (APC 5114) Hospital outpatient department	$7,413.38
ASC (PI J8) Ambulatory surgical center (freestanding)	$4,682.29

Common denial reasons

The recurring reasons claims for CPT 21740 get rejected.

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

Missing or insufficient pre-authorization: payers commonly require documented Haller index, pulmonary function data, or failed conservative management before approving 21740.
Diagnosis-procedure mismatch: billing 21740 without a supporting congenital chest wall deformity ICD-10 code (e.g., Q67.6 or Q67.7) triggers automatic claim rejection.
Upcoding or unlisted-code confusion: using 21740 for acquired sternal deformities (post-cardiac surgery, trauma) rather than congenital conditions is a common medical necessity denial trigger.
Postoperative visits billed without modifier 24 or 79 during the 90-day global period, causing bundling denials.
Incomplete operative documentation: notes lacking technique name or objective deformity measurement fail clinical review during audits and appeals.

Frequently asked questions

Source · Generated from the editorial pipeline, verified against 5 cited references ↓

01Does 21740 cover both pectus excavatum and pectus carinatum repairs?

Yes. 21740 applies to open sternal reconstruction for both deformities. Pair with the appropriate ICD-10: Q67.6 for pectus excavatum or Q67.7 for pectus carinatum. The specific deformity should be named in the operative note.

02What global period applies, and what can be billed during it?

21740 carries a 90-day global. Routine postoperative visits are bundled. Bill E/M services unrelated to the reconstruction with modifier 24. Bill unrelated procedures with modifier 79. A related unplanned return to the OR uses modifier 78.

03Does payer authorization typically require a Haller index?

Most commercial payers and many Medicare Advantage plans require a CT-derived Haller index of 3.25 or higher for pectus excavatum. Some also require documentation of cardiopulmonary symptoms or failed bracing. Confirm the specific threshold in each payer's medical policy before submission.

04Can 21740 be billed with modifier 22 for an unusually complex reconstruction?

Yes, if the work was substantially greater than typical — extensive cartilage involvement, revision of prior repair, or prolonged operative time. Document increased time, complexity, or anatomic difficulty explicitly in the operative note. Modifier 22 without supporting narrative is routinely stripped on audit.

05Is 21740 ever billed bilaterally with modifier 50?

No. The sternum is a midline structure; modifier 50 doesn't apply. Modifier 50 is for procedures on bilateral paired anatomic structures (e.g., paired extremities or organs).

06What ICD-10 codes pair with 21740 for congenital sternal deformities?

Q67.6 (pectus excavatum) and Q67.7 (pectus carinatum) are the primary diagnosis codes. Using an acquired or unspecified chest deformity code without a congenital qualifier is a common trigger for medical necessity denial.

Sources & references

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

Mira Scribe

Mira's AI scribe captures the deformity type and severity metric (e.g., Haller index), the named surgical technique, hardware or implant details, and intraoperative findings from the surgeon's dictation — the exact elements payers pull during medical necessity review. That prevents the most common denial pattern for 21740: authorization approvals that don't match the operative note because severity documentation was vague or technique-specific language was missing.

See how Mira captures CPT 21740 documentation