Radical resection of a tumor from the tibia, including removal of wide margins of normal surrounding bone tissue.

Verified May 8, 2026 · 7 sources ↓

Medicare: $1,589.21
Total RVUs: 47.58
Global, days: 90
Region: Foot & ankle

Drawn from CMSAacpmAAOSAAPC

Documentation requirements

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

Source · Editorial brief grounded in 7 cited references ↓

Pathology or imaging confirming tibial tumor requiring radical resection (not benign cyst/curettage)
Operative note specifying extent of bony resection and margin strategy — do not use generic language like 'tumor removed'
Documentation distinguishing radical resection from simple excision or curettage to support 27645 over 27635/27637
If modifier 22 is appended, documentation of the specific factors increasing intraoperative complexity beyond typical (e.g., prior radiation, anatomic distortion, neurovascular involvement)
If staged reconstruction is planned, document intent in the original operative note to support modifier 58 on subsequent procedure
Pre-operative imaging report (MRI or CT) in the medical record to establish lesion extent and surgical necessity

Applicable modifiers

Modifiers commonly billed with this code.

Source · AMA CPT modifier descriptors · CMS NCCI Policy Manual

22 Increased complexity 51 Multiple procedures 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 LT Left side RT Right side

What this code covers

Source · Editorial summary grounded in 7 cited references ↓

CPT 27645 covers radical resection of a tibial tumor — the kind of aggressive surgical excision required for primary bone malignancies or severe osteomyelitis where wide, oncologic margins are necessary. This is distinct from simple excision or curettage (27635–27637), which are appropriate for benign lesions. Radical resection implies removal of the tumor plus a cuff of normal tissue sufficient to achieve clear margins, often requiring structural reconstruction planning.

The code carries a 90-day global period. All routine post-op visits, wound checks, and dressing changes through day 90 are included in the global package. If the patient is seen during that window for an unrelated problem, append modifier 24 to the E/M. If a staged reconstructive procedure is planned and documented in the original operative note, use modifier 58 on the subsequent surgery — that resets the global clock. An unplanned return for a related complication gets modifier 78; an unrelated operative intervention gets modifier 79.

Site of service matters here. HOPD and ASC payment rates differ significantly — see the Site of Service comparison rendered on this page. For payers requiring prior authorization, confirm that the diagnosis (primary bone tumor vs. metastatic lesion vs. chronic osteomyelitis) maps correctly to the ICD-10 submitted, since ICD-diagnosis mismatches are a leading denial trigger for this high-RVU code.

RVU & reimbursement

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

Source · CMS Physician Fee Schedule, RVU26A · January 2026

Work RVU	26.53
Practice expense RVU	15.41
Malpractice RVU	5.64
Total RVU	47.58
Medicare national rate	$1,589.21
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	$1,589.21
HOPD (APC 5113) Hospital outpatient department	$3,342.87
ASC (PI G2) Ambulatory surgical center (freestanding)	$1,644.87

Common denial reasons

The recurring reasons claims for CPT 27645 get rejected.

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

ICD-10 diagnosis code does not support radical resection — benign tumor diagnosis paired with 27645 instead of 27635
Insufficient operative note detail: notes that omit margin documentation or describe 'standard excision' without radical resection language
Modifier 22 claimed without supporting documentation of substantially increased operative time or complexity
Global period conflict: E/M or minor procedure billed within 90-day global without appropriate modifier 24 or 79
Site of service mismatch between place-of-service code on claim and actual facility where procedure was performed

Frequently asked questions

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

01What distinguishes 27645 from 27635 or 27637?

27645 is radical resection — oncologic margins, typically for malignant tumors or severe osteomyelitis. 27635 and 27637 cover excision or curettage of benign cysts or tumors, with 27637 adding autograft. Pairing a benign diagnosis ICD-10 with 27645 is a reliable denial trigger.

02Does 27645 carry a global period, and what does it include?

Yes — 90-day global. Routine post-op visits, wound care, and stitch removal through day 90 are bundled. Bill unrelated E/M services in the global window with modifier 24. Planned staged reconstruction uses modifier 58 and resets the global clock.

03When is modifier 22 appropriate for 27645?

Use modifier 22 when documented intraoperative complexity substantially exceeds typical radical resection — examples include prior radiation to the field, extensive neurovascular dissection, or significantly distorted anatomy. The operative note must quantify or describe the additional work; vague language won't survive audit.

04Can 27645 and 27646 be billed together if both tibia and fibula tumors are resected in the same session?

Yes. If separate radical resections are performed on the tibia and fibula at the same operative session, both 27645 and 27646 may be reported. Append modifier 51 to the lower-valued procedure. Document each resection as a distinct procedure in the operative note.

05How should a return to the OR during the 90-day global be coded?

A return for a complication related to the original resection (e.g., wound dehiscence requiring operative repair) uses modifier 78. A return for a completely unrelated procedure uses modifier 79. A planned staged reconstruction documented in advance uses modifier 58. Do not use 78 and 79 interchangeably — payers audit this.

06Is prior authorization typically required for 27645?

Most commercial payers and Medicare Advantage plans require prior authorization for radical bone resection. Confirm that the auth request specifies the correct ICD-10 (primary vs. metastatic vs. osteomyelitis) — auth granted for one diagnosis category does not automatically cover another, and mismatches cause post-payment recoupment.

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 surgical approach, extent of tibial resection, margin description, and any complicating factors (prior radiation field, neurovascular proximity, abnormal anatomy) directly from dictation. This prevents the most common audit flag for 27645: an operative note that documents tumor removal without specifying the radical resection technique, margin width, or clinical rationale — the documentation gap that turns a correctly coded claim into a downcode to 27635.

See how Mira captures CPT 27645 documentation