Surgical · Knee

Excision or curettage of a bone cyst or benign tumor of the femur, without graft or internal fixation.

Verified May 8, 2026 · 5 sources ↓

Medicare: $577.50
Work RVU: 7.8
Global, days: 90
Region: Knee

Drawn from CMSAbosAAOS

Documentation requirements

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

Source · Editorial brief grounded in 5 cited references ↓

Operative report must identify the specific anatomic location of the lesion on the femur (distal, diaphyseal, proximal) — vague references to 'femoral lesion' without location are an audit flag.
Confirm no graft material was used; if methylmethacrylate cement or bone substitute was packed, document the material and volume to support the correct code selection.
Specify that no internal fixation was placed — absence of fixation is what distinguishes 27355 from the add-on 27358.
Pathology submission documentation is required; the operative note should state the specimen was sent for permanent or frozen section analysis.
Pre-operative imaging (MRI, CT, or plain film) identifying the lesion as a cyst or benign tumor must be in the record to support medical necessity and the corresponding ICD-10 diagnosis.
Document the surgical approach and method — curettage versus en bloc excision — as audit teams flag operative notes that omit technique.

Applicable modifiers

Modifiers commonly billed with this code.

Source · AMA CPT modifier descriptors · CMS NCCI Policy Manual

22 Increased complexity 51 Multiple procedures 59 Distinct service LT Left side RT Right side 80 Assistant surgeon AS PA/NP/CNS assistant 62 Co-surgeons

What this code covers

Source · Editorial summary grounded in 5 cited references ↓

CPT 27355 covers open excision or curettage of a bone cyst or benign tumor of the femur when performed without bone grafting or internal fixation. The code sits at the base of a four-code family: 27356 adds allograft, 27357 adds autograft (including harvest), and 27358 is an add-on for internal fixation. Bill 27355 alone only when the defect is left without graft material and no fixation is placed — if either is added intraoperatively, the higher-specificity code applies.

The 90-day global period means all routine post-op care through day 90 is bundled — no separate E/M unless it meets modifier 24 criteria (unrelated condition). Pathology specimen processing is separately reportable and does not require modifier 59 because it falls under a different CPT section. Intraoperative fluoroscopy used for lesion localization is generally considered integral and is not separately billable under NCCI policy.

Site of service matters here: the HOPD and ASC facility payments differ substantially, and physician work RVUs remain constant regardless of setting. When the case is performed in an ASC, confirm the facility has 27355 on its covered procedures list — payer contracts occasionally exclude lower-volume musculoskeletal excision codes.

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 (7.8) is the surgeon's own effort — the figure physician pay and productivity targets are built on. The total RVU (17.29) adds practice overhead and malpractice, and is what drives the Medicare payment below.

Work RVU	7.8
Practice expense RVU	7.85
Malpractice RVU	1.64
Total RVU	17.29
Medicare national rate	$577.50
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	$577.50
HOPD (APC 5113) Hospital outpatient department	$3,342.87
ASC (PI A2) Ambulatory surgical center (freestanding)	$1,644.87

Common denial reasons

The recurring reasons claims for CPT 27355 get rejected.

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

Upcoding to 27356 or 27357 when no graft was placed — payers cross-reference the operative note and pathology report for graft material.
Missing or non-specific ICD-10 diagnosis: a noncommittal 'lesion of femur' without a benign tumor or cyst code (e.g., M85.x, D16.2x) is a top CPT-ICD mismatch denial trigger.
Separate billing of intraoperative fluoroscopy guidance — NCCI bundles routine imaging used for lesion localization into the surgical code.
Billing an E/M on the same date without modifier 25, or billing a routine post-op visit within the 90-day global without modifier 24.
Add-on 27358 billed without a primary procedure code — 27358 is not a standalone code and will deny without 27355, 27356, or 27357 as the primary.

Frequently asked questions

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

01When should I use 27356 instead of 27355?

Bill 27356 when the defect is filled with allograft bone after excision or curettage. If the surgeon packed with autograft harvested at the same session, use 27357. Reserve 27355 strictly for cases where the defect is left without any graft material.

02Is 27358 a standalone code or an add-on?

27358 is an add-on code. It must be listed in addition to 27355, 27356, or 27357. Submitting it as a standalone code will result in a denial. Do not append modifier 51 to an add-on code.

03Can I bill pathology separately when the excised lesion is sent for analysis?

Yes. Surgical pathology codes (88300–88309) are separately reportable because they fall outside the surgical CPT section. Modifier 59 is not required to unbundle them from 27355.

04What modifier do I use if a routine post-op visit within the 90-day global is for an unrelated condition?

Use modifier 24 on the E/M code to indicate the visit is unrelated to the femur procedure. Document clearly in the note why the visit is distinct — same-day unrelated E/M within the global will be reviewed.

05Can I bill modifier 22 if the tumor was unusually large or the resection was significantly more complex than typical?

Yes, but documentation must support it. The operative note must describe specific factors — size, location, proximity to neurovascular structures, or extended operative time — that made the work substantially greater than the typical 27355. A brief note saying 'complex case' won't survive audit.

06Does site of service affect my reimbursement for 27355?

It affects facility payment but not your physician work RVUs. The HOPD facility rate is higher than the ASC rate. Your professional fee is calculated the same way in both settings, though the non-facility versus facility RVU split affects your practice expense component. See the Site of Service comparison table.

Sources & references

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

Mira Scribe

Mira's AI scribe captures the lesion's anatomic location on the femur, surgical method (curettage vs. excision), graft status (none, allograft, autograft), fixation status, and specimen disposition from dictation. That prevents the most common denial scenario: a claim coded as 27355 that the operative note contradicts by describing graft packing or cement use, which should be 27356 or escalated with modifier 22.

See how Mira captures CPT 27355 documentation