Fasciotomy releasing one compartment of the thigh and/or knee — either flexor, extensor, or adductor — to relieve elevated intracompartmental pressure.

Verified May 8, 2026 · 7 sources ↓

Medicare: $531.07
Total RVUs: 15.9
Global, days: 90
Region: Knee

Drawn from CMSAAPCFindacodeAAOSCgsmedicare

Documentation requirements

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

Source · Editorial brief grounded in 7 cited references ↓

Identify the specific compartment released: flexor, extensor, or adductor — not just 'thigh fasciotomy'
Document the clinical indication: measured intracompartmental pressures or clear clinical signs of compartment syndrome
Record laterality explicitly (left or right thigh/knee) for modifier and claims accuracy
Describe wound management: whether the fasciotomy was left open, partially closed, or packed, and the plan for staged closure
Note whether the procedure was urgent/emergent and the precipitating event (trauma, crush, vascular complication, etc.)
If a staged return for closure is anticipated, document that intention in the initial operative note to support modifier 58 on the subsequent procedure

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 57 Decision for surgery 58 Staged or related 59 Distinct service 78 Unplanned return — related 79 Unrelated during global 80 Assistant surgeon LT Left side RT Right side AS PA/NP/CNS assistant

What this code covers

Source · Editorial summary grounded in 7 cited references ↓

27496 describes a single-compartment decompression fasciotomy of the thigh and/or knee. The surgeon incises the fascia of one compartment — flexor, extensor, or adductor — to reduce intracompartmental pressure, restore perfusion, and prevent or treat compartment syndrome. The procedure is most commonly performed as an urgent or emergent intervention following trauma, crush injury, reperfusion injury, or as a complication of vascular surgery.

The 90-day global period means the surgery, the day-before visit, and all routine postoperative care are bundled through day 90. Any E/M visit on the day of surgery for a separate, unrelated problem needs modifier 25. A decision-for-surgery visit the day before or day of requires modifier 57 appended to the E/M code. If additional compartments are released in the same operative session, escalate to 27497 (two or more compartments) — do not stack multiple units of 27496.

Site-of-service choice matters here. HOPD payment exceeds ASC payment substantially (see the Site of Service comparison table). Because this is frequently performed emergently, the operative note must document the specific compartment released, the clinical indication (measured pressures or clinical diagnosis), laterality, and the wound management plan — open fasciotomies typically require a planned return for closure or skin grafting, which should be noted as a staged procedure.

RVU & reimbursement

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

Source · CMS Physician Fee Schedule, RVU26A · January 2026

Work RVU	6.61
Practice expense RVU	7.89
Malpractice RVU	1.4
Total RVU	15.9
Medicare national rate	$531.07
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	$531.07
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 27496 get rejected.

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

Operative note documents 'fasciotomy' without specifying the compartment released, making the code unverifiable on audit
Bilateral procedures billed as two line items without modifier 50, or billed with modifier 50 but as two units rather than one line
Modifier 58 missing on the staged closure or skin graft procedure performed within the 90-day global, causing it to deny as included postoperative care
Upcoding to 27497 (two or more compartments) when only one compartment is documented — payers audit operative notes for compartment count
E/M billed same-day without modifier 25 when the visit addressed the same diagnosis driving the fasciotomy

Frequently asked questions

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

01What is the difference between 27496 and 27497?

27496 covers release of one compartment (flexor, extensor, or adductor) in the thigh and/or knee. 27497 is used when two or more compartments are released in the same operative session. The compartment count in the operative note drives the code selection — bill the higher code only if the documentation explicitly confirms multiple compartments were opened.

02Can 27496 and 27497 both be billed on the same day?

No. 27497 (two or more compartments) is the comprehensive code when multiple compartments are addressed. Billing both 27496 and 27497 together is incorrect — use whichever matches the documented compartment count.

03The patient returns within the global period for fasciotomy wound closure. How do I bill that?

Use modifier 58 on the closure or skin graft code. The return was planned and staged — that is exactly what modifier 58 is for. Document the intention for staged closure in the original operative note. Modifier 58 resets the global period for the closure procedure.

04How do I bill a bilateral same-session thigh fasciotomy?

Append modifier 50 to 27496 and bill one line. Some payers require LT and RT on separate lines — verify payer preference before submission. Per CMS, reimbursement for a bilateral procedure is capped at 150% of the single-procedure fee schedule amount.

05Is an E/M visit billable on the same day as 27496?

Yes, if the E/M visit addressed a problem separate from the compartment syndrome driving the fasciotomy. Append modifier 25 to the E/M code and document the distinct medical decision-making in the visit note. If the visit was a decision-for-surgery visit the day before or day of, append modifier 57 to the E/M instead.

06Does modifier 22 apply to a particularly complex fasciotomy?

It can, but only when the work is substantially greater than typical — for example, severely compromised tissue planes from prior surgery, extensive necrosis requiring additional dissection, or unusual anatomic complexity. The operative note must describe the specific factors that increased operative time and difficulty. Payers scrutinize modifier 22 claims; a note that simply states 'difficult procedure' will not support it.

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 compartment name (flexor, extensor, or adductor), laterality, clinical indication including any documented pressure measurements, and the wound management plan from dictation. This prevents the most common audit flag for 27496 — an operative note that says 'thigh fasciotomy' without specifying which compartment was released — and ensures the staged-closure plan is in the record before the 90-day global clock starts.

See how Mira captures CPT 27496 documentation