Open incisional biopsy of superficial soft tissue in the thigh or knee area, requiring a skin incision to obtain tissue for pathologic analysis.

Verified May 8, 2026 · 5 sources ↓

Medicare: $274.89
Total RVUs: 8.23
Global, days: 10
Region: Knee

Drawn from CMSAAPCFindacodeGenhealthMdclarity

Documentation requirements

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

Source · Editorial brief grounded in 5 cited references ↓

Confirm that an incision was made — needle-only approaches do not support 27323
Explicitly document the lesion's relationship to the deep fascia (superficial vs. deep) to justify the level selected
Record lesion size, location (e.g., anterior thigh, medial knee area), and laterality (left vs. right)
Document pre- and postoperative diagnosis, including any clinical suspicion driving the biopsy indication
Note whether imaging guidance was used; if so, document the guidance modality separately for add-on billing

Applicable modifiers

Modifiers commonly billed with this code.

Source · AMA CPT modifier descriptors · CMS NCCI Policy Manual

22 Increased complexity 24 Unrelated E/M during global 25 Significant separate E/M 50 Bilateral procedure 51 Multiple procedures 59 Distinct service 76 Repeat, same physician 77 Repeat, another physician 78 Unplanned return — related 79 Unrelated during global LT Left side RT Right side

What this code covers

Source · Editorial summary grounded in 5 cited references ↓

CPT 27323 covers an open, incisional biopsy of superficial soft tissue located in the thigh or knee region. The surgeon makes a skin incision, dissects to the target lesion, and removes a tissue sample — distinguishing this from needle-based techniques. If no incision is made and the surgeon uses a needle (core or fine needle), report 20206 instead. That distinction is the most common coding error on thigh soft tissue biopsies.

The superficial designation matters: 27323 applies when the lesion is above the deep fascia. Deep soft tissue biopsy of the same region — below the fascia or intramuscular — is reported with 27324. Operative notes that fail to document the relationship of the mass to the deep fascia give auditors and payers grounds to question the level billed.

The global period is 10 days. Routine follow-up within that window is included. If imaging guidance (e.g., ultrasound) is used to direct needle placement, the guidance code is separately billable — but again, once you add US-guided needle placement, confirm whether 27323 is still the right base code versus 20206.

RVU & reimbursement

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

Source · CMS Physician Fee Schedule, RVU26A · January 2026

Work RVU	2.27
Practice expense RVU	5.66
Malpractice RVU	0.3
Total RVU	8.23
Medicare national rate	$274.89
Global period	10 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	$274.89
HOPD (APC 5072) Hospital outpatient department	$1,687.37
ASC (PI A2) Ambulatory surgical center (freestanding)	$742.04

Common denial reasons

The recurring reasons claims for CPT 27323 get rejected.

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

Downcoded to 20206 when operative note describes needle biopsy technique rather than open incisional approach
Upcoded challenge to 27324 rejected when fascia depth is not documented and payer defaults to superficial
Missing laterality modifier causes claim suspension or rejection under payers requiring LT/RT on unilateral procedures
Lack of medical necessity documentation when pathology indication (mass characteristics, prior imaging) is absent from the note

Frequently asked questions

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

01What is the difference between 27323 and 20206 for a thigh biopsy?

27323 requires an open skin incision for tissue removal. 20206 is the correct code when a needle — including a core needle with ultrasound guidance — is used and no incision is made. Using 27323 for a needle procedure is a common overcoding error that auditors flag.

02When should I use 27324 instead of 27323?

Use 27324 when the biopsy is of deep soft tissue — below the deep fascia or within muscle. 27323 is limited to superficial tissue above the fascia. Your operative note must document the fascial depth to support whichever level you bill.

03Do I need a laterality modifier on 27323?

Yes. Append LT or RT to identify which thigh was biopsied. Many payers require laterality on unilateral musculoskeletal procedures, and omitting it is a common reason for claim suspension.

04Can I separately bill ultrasound guidance when performing this biopsy?

If imaging guidance was used to direct needle placement, the guidance code may be separately billable — but also reconsider whether 27323 remains the correct base code. An ultrasound-guided needle biopsy with no incision typically maps to 20206 plus the applicable guidance code.

05What is the global period for 27323, and what does it include?

27323 carries a 10-day global period. Routine post-op visits, dressing changes, and wound checks within those 10 days are included. An unrelated E/M during that window requires modifier 24; a related staged or repeat procedure needs modifier 78 or 79 depending on whether it is related to the original biopsy.

06Why does dermatology show as a top-billing specialty for 27323?

Dermatologists frequently encounter and biopsy thigh soft tissue masses in the office setting. Orthopedic practices billing this code should ensure their documentation reflects the open surgical approach, as audit profiles may be shaped by dermatology-style notes that describe shave or punch techniques not consistent with 27323.

Sources & references

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

01CMS Physician Fee Schedule 2026
02
aapc.com
https://www.aapc.com/codes/cpt-codes/27323
03
findacode.com
https://www.findacode.com/cpt/27323-cpt-code.html
04
genhealth.ai
https://genhealth.ai/code/cpt4/27323-biopsy-soft-tissue-of-thigh-or-knee-area-superficial
05
mdclarity.com
https://www.mdclarity.com/cpt-code/27323

Mira AI Scribe

Mira's AI scribe captures the surgical approach (incisional vs. needle), the lesion's anatomic depth relative to the deep fascia, size and location of the mass, and laterality from the operative dictation. This prevents the two most common downcodes on 27323: miscoding an open biopsy as 20206 (needle) and losing the superficial vs. deep distinction that separates 27323 from 27324.

See how Mira captures CPT 27323 documentation