Surgical excision of the prepatellar bursa — the fluid-filled sac anterior to the kneecap — performed to relieve chronic bursitis-related pain and inflammation.

Verified May 8, 2026 · 6 sources ↓

Medicare: $369.75
Total RVUs: 11.07
Global, days: 90
Region: Knee

Drawn from CMSAbosFindacodeAAPCAAOS

Documentation requirements

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

Source · Editorial brief grounded in 6 cited references ↓

Operative note must state the bursa was excised — not just drained or aspirated — with anatomic location specified (prepatellar vs. other knee bursa)
Document the clinical indication: duration of conservative treatment failure, imaging or aspiration results supporting chronic bursitis diagnosis
Specify laterality (left, right, or bilateral) in both the operative note and diagnosis coding
If billing same-day with another knee procedure, document that each procedure was distinct and medically necessary in its own right
Preoperative diagnosis must align with ICD-10 (e.g., M70.40–M70.42 for prepatellar bursitis) and match the surgical findings

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 76 Repeat, same physician 78 Unplanned return — related 79 Unrelated during global LT Left side RT Right side AS PA/NP/CNS assistant XS Separate structure

What this code covers

Source · Editorial summary grounded in 6 cited references ↓

CPT 27340 covers open excision of the prepatellar bursa, the synovial sac sitting directly in front of the patella. The procedure is distinct from incision and drainage (27301): the surgeon must actually excise the bursa, not simply drain it. If the operative note documents only aspiration or I&D, 27340 does not apply — use 27301 instead. Auditors look for this distinction specifically.

The code also surfaces in pretibial bursectomy cases. CPT has no dedicated pretibial bursectomy code, so 27340 is the closest analog — but only when the surgeon's documented work mirrors a prepatellar excision in scope. Confirm the anatomy and the extent of resection before submitting.

The 90-day global period means all routine post-op knee visits, wound checks, and dressing changes through day 90 are bundled. Bill modifier 24 for unrelated E/M visits in that window, modifier 78 for an unplanned return to the OR for a related complication, and modifier 79 for an unrelated procedure performed during the global period.

RVU & reimbursement

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

Source · CMS Physician Fee Schedule, RVU26A · January 2026

Work RVU	4.21
Practice expense RVU	5.98
Malpractice RVU	0.88
Total RVU	11.07
Medicare national rate	$369.75
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	$369.75
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 27340 get rejected.

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

Operative note documents incision and drainage only — payer downcodes or denies 27340 in favor of 27301
Missing or ambiguous laterality leads to claim suspension or rejection pending clarification
Routine post-op E/M visit billed without modifier 24 during the 90-day global period
Medical necessity not established — no documented trial of conservative management (rest, aspiration, anti-inflammatory therapy) prior to surgery
Bundling conflict when billed same-day with a more extensive knee procedure without modifier 59 or XS to establish distinct service

Frequently asked questions

Source · Generated from the editorial pipeline, verified against 6 cited references ↓

01What's the difference between 27340 and 27301 for a knee bursa procedure?

27301 covers incision and drainage of a deep bursa or abscess in the knee region. 27340 requires actual excision of the prepatellar bursa. If the surgeon drained the bursa without removing it, bill 27301. The operative note has to document excision — not just decompression — to support 27340.

02Can 27340 be used for a pretibial bursectomy?

CPT has no specific pretibial bursectomy code. 27340 is the closest analog and is the code most commonly applied, but only when the surgeon's work is comparable in scope to a prepatellar excision. Document the anatomy precisely and confirm payer acceptance before submitting.

03Can 27340 be billed bilaterally?

Yes. Use modifier 50 for a true bilateral same-session excision. Append LT and RT individually if your payer requires line-item laterality instead of a single 50-modified line. Confirm payer preference — some commercial payers reject modifier 50 and require separate lines.

04What modifier applies if the patient returns to the OR for a wound complication after 27340?

Modifier 78 covers an unplanned return to the OR for a complication related to the original procedure during the 90-day global period. If the return procedure is unrelated to the bursectomy, use modifier 79 instead. Do not invert these — using 79 for a related complication is an audit flag.

05Can 27340 and 27360 be billed together?

Potentially, if both procedures are clearly distinct and separately documented. NCCI edits and payer policies vary, so modifier 59 or XS may be required to bypass a bundling edit. The operative note must support independent medical necessity for each procedure. Check current NCCI PTP edits before submitting.

06What global period applies to 27340, and what does that include?

27340 carries a 90-day global period. That covers the surgery, the day-before pre-op visit, and all routine post-op knee care through day 90 — including wound checks, suture removal, and dressing changes. An E/M for an unrelated condition during that window needs modifier 24.

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 bursa excised (prepatellar vs. pretibial), the surgical method confirming full excision rather than drainage, laterality, and the duration and type of prior conservative treatment that failed. That documentation prevents the most common denial for 27340: operative notes that describe drainage only, which triggers a downcode to 27301 and a significant reimbursement gap.

See how Mira captures CPT 27340 documentation