20957

Microvascular bone graft harvested from the metatarsal, transferred to a recipient site with microsurgical vascular anastomosis to restore active blood supply.

Verified May 8, 2026 · 9 sources ↓

Medicare: $2,456.30
Total RVUs: 73.54
Global, days: 90
Region: Foot & ankle

Drawn from CMSMdclarityFindacodeAAPCBedrockbilling

Documentation requirements

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

Source · Editorial brief grounded in 9 cited references ↓

Identify the donor site explicitly as metatarsal, including which metatarsal and laterality
Describe the vascular pedicle: artery and vein harvested, length, and caliber
Document microsurgical anastomosis technique (end-to-end, end-to-side) and confirmation of perfusion at the recipient site
Specify the recipient site defect: location, dimensions, and underlying pathology requiring vascularized graft
Record intraoperative perfusion assessment (Doppler, bleeding response, or fluorescence imaging) confirming graft viability
If modifier 22 is appended, document specific factors — redo field, vessel anomaly, prolonged ischemia time — that increased operative complexity beyond the norm
If modifier 62 is used, each surgeon's operative note must delineate their distinct role and work

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 59 Distinct service 62 Co-surgeons 76 Repeat, same physician 77 Repeat, another physician 78 Unplanned return — related 79 Unrelated during global 80 Assistant surgeon LT Left side RT Right side

What this code covers

Source · Editorial summary grounded in 9 cited references ↓

CPT 20957 covers harvest of a metatarsal bone graft along with its native arterial and venous supply, followed by microsurgical anastomosis at the recipient site. The live vascular connection distinguishes this from avascular cortical or cancellous grafts — the bone arrives with a functioning blood supply, accelerating incorporation and reducing the risk of graft resorption. The procedure demands two distinct operative fields and microsurgical expertise, which drives its high work RVU and 90-day global period.

The 90-day global includes the day-before visit, the surgical day, and all routine postoperative care through day 90. Any E/M unrelated to graft recovery during that window requires modifier 24. A return to the OR for a complication directly related to the graft — vascular thrombosis, flap compromise — bills with modifier 78. An unrelated procedure during the global uses modifier 79.

When two surgeons perform distinct portions of the microsurgical reconstruction simultaneously (e.g., one team harvests, one prepares the recipient site), each surgeon appends modifier 62 and bills 20957 at 62.5% of the fee schedule. If the complexity of the vascular work materially exceeds the typical case — unusual anatomy, redo harvest, prolonged anastomosis time — document specifics and append modifier 22 with a cover letter explaining the added work.

RVU & reimbursement

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

Source · CMS Physician Fee Schedule, RVU26A · January 2026

Work RVU	41.54
Practice expense RVU	23.14
Malpractice RVU	8.86
Total RVU	73.54
Medicare national rate	$2,456.30
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	$2,456.30
HOPD (APC 5114) Hospital outpatient department	$7,413.38
ASC (PI J8) Ambulatory surgical center (freestanding)	$4,682.29

Common denial reasons

The recurring reasons claims for CPT 20957 get rejected.

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

Operative note fails to document microsurgical anastomosis, causing payer to downcode to a non-vascularized graft code
Missing laterality or metatarsal level makes claim non-specific and triggers request for additional documentation
Graft harvest coded separately when the code descriptor for the primary reconstruction already includes procurement — NCCI bundles the harvest
E/M service billed during the 90-day global without modifier 24 and a diagnosis clearly unrelated to graft recovery
Modifier 62 used without each surgeon submitting a separate operative note documenting distinct, simultaneous work

Frequently asked questions

Source · Generated from the editorial pipeline, verified against 9 cited references ↓

01What separates 20957 from 20962?

20957 is specific to a metatarsal donor site with microvascular anastomosis. 20962 covers vascularized bone grafts from donor sites other than fibula (20955), iliac crest (20956), or metatarsal (20957). Use 20957 only when the metatarsal is the harvest source.

02Can I bill for graft harvest separately when reporting 20957?

No. The harvest is integral to 20957. NCCI policy and the code structure both treat procurement as included. Billing a separate harvest code alongside 20957 will trigger a bundling denial.

03When does modifier 62 apply to this procedure?

Use modifier 62 when two surgeons each perform a distinct, primary portion of the same microvascular procedure simultaneously — for example, one surgeon harvests the metatarsal pedicle while the other prepares the recipient vessels. Both surgeons bill 20957-62. Each must have an independent operative note documenting their specific work.

04How is a vascular complication during the 90-day global handled?

An unplanned return to the OR for anastomotic thrombosis or graft compromise — directly related to the index procedure — bills with modifier 78. The global clock does not restart. Modifier 79 applies only if the return OR visit is for a completely unrelated condition.

05Is 20957 payable in an ASC setting?

Yes. CMS assigns an ASC payment rate to 20957 that differs from the HOPD rate — see the Site of Service comparison table on this page. Verify your payer's ASC-approved list before scheduling; some commercial payers require hospital outpatient or inpatient setting for microvascular procedures of this complexity.

06Does modifier 50 apply if bilateral metatarsal grafts are harvested?

Bilateral harvest from both feet in a single session is extremely rare clinically, but if it occurs, report 20957-50 for professional billing. ASCs follow different rules: report two lines with modifiers LT and RT respectively. Confirm payer policy, as some payers require prior authorization for bilateral microvascular procedures.

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 donor metatarsal level, vascular pedicle details (artery, vein, caliber), anastomosis technique, and intraoperative perfusion confirmation from dictation. That prevents downcoding to an avascular graft code — the single most common audit flag on 20957 — by ensuring the operative note explicitly supports microvascular work before the claim leaves the practice.

See how Mira captures CPT 20957 documentation