Surgical decompression of the thigh and/or knee compartments, typically performed for acute or impending compartment syndrome.

Verified May 8, 2026 · 5 sources ↓

Medicare: $551.78
Work RVU: 7.6
Global, days: 90
Region: Knee

Drawn from CMSCgsmedicareAAHKS

Documentation requirements

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

Source · Editorial brief grounded in 5 cited references ↓

Documented compartment pressure measurements or clinical findings (pain with passive stretch, tense compartment, paresthesias, pallor) supporting diagnosis of compartment syndrome
Identification of the specific fascial compartment(s) released — anterior, posterior, and/or medial thigh
Operative note documenting the length and location of incisions and extent of fascial release
Pre- and intraoperative neurovascular assessment including distal pulses and motor/sensory function
Documentation of wound management decision — open, VAC, or primary closure — and whether staged closure is planned
If bilateral, explicit documentation that both thighs required decompression with clinical justification for each side

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 58 Staged or related 59 Distinct service 62 Co-surgeons 78 Unplanned return — related 79 Unrelated during global 80 Assistant surgeon AS PA/NP/CNS assistant LT Left side RT Right side XS Separate structure

What this code covers

Source · Editorial summary grounded in 5 cited references ↓

CPT 27497 covers open fasciotomy of the thigh and/or knee region to relieve elevated intracompartmental pressure. This is an urgent or emergent procedure indicated when compartment pressures threaten muscle and neurovascular viability — most commonly following trauma, crush injury, vascular repair, or prolonged external compression. The surgeon opens one or more fascial compartments of the thigh (anterior, posterior, medial) through longitudinal incisions sufficient to fully decompress the affected tissue.

The 90-day global period means all routine follow-up, wound checks, and dressing changes through day 90 are bundled. Secondary wound closure or skin grafting required after initial decompression, if performed at a separate operative session, falls outside the original global if it qualifies as a staged procedure — use modifier 58. An unrelated procedure in the global window needs modifier 79. If a return to the OR is required for a related complication, modifier 78 applies.

Because compartment syndrome decompression is almost always unilateral and driven by a discrete traumatic event, bilateral billing (modifier 50) is rare and requires explicit documentation of bilateral involvement. When 27497 is performed in the context of a more extensive vascular or orthopedic procedure on the same day, NCCI bundling rules must be reviewed carefully before reporting both codes — consult the NCCI PTP lookup for current edit pairs and modifier indicators.

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 (7.6) is the surgeon's own effort — the figure physician pay and productivity targets are built on. The total RVU (16.52) adds practice overhead and malpractice, and is what drives the Medicare payment below.

Work RVU	7.6
Practice expense RVU	7.3
Malpractice RVU	1.62
Total RVU	16.52
Medicare national rate	$551.78
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	$551.78
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 27497 get rejected.

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

Missing or inadequate compartment pressure measurements or clinical criteria in the operative or pre-op note
Bundling denial when billed same-day with a related vascular or orthopedic procedure without appropriate modifier
Modifier 50 appended without documentation demonstrating bilateral compartment syndrome
Staged wound closure or skin grafting billed without modifier 58, triggering global period denial
Operative note fails to specify which compartments were released, prompting medical necessity review

Frequently asked questions

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

01What is the global period for CPT 27497?

90 days. Routine post-op visits, wound checks, and dressing changes through day 90 are bundled. Staged closure or grafting at a separate session uses modifier 58.

02Can I bill 27497 with a same-day vascular repair code?

It depends on the NCCI edit pair. Check the CMS NCCI PTP lookup for the specific vascular code. If the modifier indicator is 1, a modifier 59 or XS can separate the services when documentation supports distinct procedures. If the indicator is 0, you cannot unbundle.

03When does modifier 78 apply versus modifier 79 after 27497?

Modifier 78 is for an unplanned return to the OR for a complication related to the original decompression — for example, re-exploration for re-accumulating pressure or wound dehiscence. Modifier 79 is for an unrelated procedure performed on the same patient during the 90-day global window.

04Is bilateral billing with modifier 50 ever appropriate for 27497?

Rarely, but yes — if both thighs required compartment release at the same operative session and documentation explicitly supports bilateral compartment syndrome. Without that documentation, payers will deny the bilateral modifier.

05How do I bill the secondary wound closure or skin graft after a thigh fasciotomy?

If the closure is planned and staged, use modifier 58 on the closure or grafting code to indicate a staged procedure within the global period. Unplanned return for a related wound complication uses modifier 78 instead.

06Does the site of service affect payment for 27497?

Yes. The HOPD and ASC payment rates differ — see the Site of Service comparison table on this page. The procedure is typically performed in a hospital setting given the emergent nature of compartment syndrome.

07What documentation distinguishes 27497 from 27496?

27496 covers decompression of the lower leg; 27497 applies to the thigh and knee. The operative note must specify the anatomic region and compartments addressed. Misidentifying the surgical site is a common upcoding or downcoding error flagged on audit.

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 compartments released, incision approach and length, intraoperative pressure measurements or clinical trigger documented, neurovascular status before and after decompression, and wound management plan including whether staged closure is anticipated. This prevents the most common audit flag — an operative note that describes fasciotomy generically without identifying which compartments were opened or why.

See how Mira captures CPT 27497 documentation