Surgical · Other

Surgical removal of a portion of a rib, performed for infection, deformity, tumor involvement, or congenital abnormality.

Verified May 8, 2026 · 7 sources ↓

Medicare: $567.82
Total RVUs: 17
Global, days: 90
Region: Other

Drawn from CMSAAPCFastrvuEmedny

Documentation requirements

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

Source · Editorial brief grounded in 7 cited references ↓

Specify which rib(s) by number and laterality (e.g., left 5th rib) — 'rib' alone is insufficient for audit defense.
State the clinical indication explicitly: osteomyelitis, deformity, tumor involvement, or congenital abnormality with supporting diagnosis codes.
Confirm the rib resection was therapeutic, not incidental to surgical approach — operative note must describe independent medical necessity.
Document extent of resection: length of segment removed, periosteal handling, and whether the pleural space was entered.
Record closure technique and whether a drain was placed, including reason if pleural entry occurred.
If billed with another procedure, note why the rib work was clinically distinct and not part of the primary exposure.

Applicable modifiers

Modifiers commonly billed with this code.

Source · AMA CPT modifier descriptors · CMS NCCI Policy Manual

22 Increased complexity 50 Bilateral procedure 51 Multiple procedures 59 Distinct service LT Left side RT Right side 78 Unplanned return — related 79 Unrelated during global 80 Assistant surgeon AS PA/NP/CNS assistant XS Separate structure

What this code covers

Source · Editorial summary grounded in 7 cited references ↓

CPT 21600 covers partial excision of a rib — meaning a segment is removed but the rib is not taken out in its entirety. Indications include osteomyelitis, rib deformity, congenital anomalies, and chest wall pathology requiring limited bone resection. The surgeon incises over the target rib, dissects through muscle and periosteum, resects the involved segment, and closes in layers; a drain may be placed if the pleural space is entered or significant dead space exists.

A critical bundling trap: when rib resection is performed solely as a surgical approach to reach another structure — such as during an XLIF exposure or thoracotomy — 21600 is not separately reportable. The resection must be the primary therapeutic procedure, not incidental access. Similarly, 21600 is bundled into certain chest wall tumor and breast reconstruction codes (e.g., 19364); check NCCI edits before billing it alongside those procedures. When a modifier bypasses the edit, modifier 59 or XS requires documentation proving the rib work was clinically distinct.

The 90-day global period means all routine post-op visits, wound checks, and staple removals through day 90 are included in the surgical payment. Unrelated E/M services during the global need modifier 24; a separate significant E/M on the day of surgery needs modifier 25 on that visit. Bilateral partial rib resection in the same session is reported with modifier 50.

RVU & reimbursement

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

Source · CMS Physician Fee Schedule, RVU26A · January 2026

Work RVU	7.08
Practice expense RVU	8.24
Malpractice RVU	1.68
Total RVU	17
Medicare national rate	$567.82
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	$567.82
HOPD (APC 5114) Hospital outpatient department	$7,413.38
ASC (PI A2) Ambulatory surgical center (freestanding)	$3,695.53

Common denial reasons

The recurring reasons claims for CPT 21600 get rejected.

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

Rib resection coded as primary procedure when operative note describes it only as part of the surgical approach to another site.
NCCI bundling denial when 21600 is billed alongside chest wall tumor or breast reconstruction codes without a valid modifier and supporting documentation.
Missing laterality or rib number causes claim to reject or pend for additional information.
Global period conflict when post-op visits are billed without modifier 24 for a related surgeon during the 90-day window.
Modifier 59 applied without documentation establishing the rib work as a distinct procedural service from the co-billed code.

Frequently asked questions

Source · Generated from the editorial pipeline, verified against 7 cited references ↓

01Can 21600 be billed when a rib is resected to gain exposure during a spine or thoracic procedure?

No. Rib resection performed solely as a surgical approach — to improve visualization or access — is bundled into the primary procedure and is not separately reportable. The rib work must carry its own therapeutic intent and medical necessity to support a standalone 21600 claim.

02Is 21600 reportable with breast reconstruction codes like 19364?

NCCI bundles 21600 into certain breast reconstruction codes. Billing it separately requires a modifier (59 or XS) and documentation proving the rib excision was a distinct service not integral to the reconstruction. Verify the specific NCCI edit pair before submitting.

03How is bilateral partial rib resection billed?

Report 21600 once with modifier 50 for bilateral resection performed in the same session. Some payers require two line items with LT and RT instead — check payer preference before submitting.

04What is the global period for 21600, and what does it cover?

21600 carries a 90-day global period. That covers the surgery, the day-before visit, and all routine post-op care through day 90. Unrelated E/M services in that window need modifier 24; a significant separate E/M on the day of surgery needs modifier 25.

05When should modifier 22 be used with 21600?

Use modifier 22 when the procedure required substantially more work than typical — for example, extensive adhesions from prior surgery, severely infected tissue requiring wider resection, or unusually complex anatomy. The operative note must quantify the additional time and describe the complicating factors specifically.

06Does 21600 require prior authorization, and what diagnosis codes support it?

Authorization requirements vary by payer. Diagnoses that commonly support medical necessity include osteomyelitis of the rib, rib deformity, chest wall infection, and benign or malignant rib lesions. Submit imaging and pathology reports with the auth request when the indication is neoplastic or infectious.

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 specific rib number, laterality, segment length removed, approach through muscle and periosteum, and the treating surgeon's stated indication from dictation. It flags operative notes that describe rib resection only in the context of surgical exposure — the single most common reason 21600 is denied on audit — before the claim is ever submitted.

See how Mira captures CPT 21600 documentation