Arthroscopic surgical procedure on the subtalar joint that includes fusion (arthrodesis) of the joint surfaces using bone graft and internal fixation.

Verified May 8, 2026 · 6 sources ↓

Medicare: $819.99
Total RVUs: 24.55
Global, days: 90
Region: Foot & ankle

Drawn from CMSCgsmedicareMdclarityEmednyAAOS

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 specify arthroscopic approach and portal placement — do not write 'standard approach'
Document the joint surface preparation method (cartilage removal technique, drilling or microfracture of subchondral bone)
Identify bone graft source and type (autograft, allograft, synthetic) and how it was placed
Name and describe all fixation hardware used (screw size, number, configuration)
State the diagnosis driving the fusion — arthritis, post-traumatic deformity, chronic instability, etc. — with supporting imaging
If modifier 22 is appended, quantify additional work and intraoperative findings that made the case more complex than typical

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 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 6 cited references ↓

CPT 29907 covers an arthroscopic subtalar arthrodesis — a minimally invasive approach to fusing the talocalcaneal joint. The surgeon accesses the joint through small portals, removes articular cartilage from the joint surfaces, places bone graft material, and stabilizes the construct with screws or other fixation. The arthroscopic approach is distinct from open subtalar fusion; documentation must specify the arthroscopic technique and the fixation method used.

The code carries a 90-day global period. All routine post-op visits, wound checks, and cast or boot changes through day 90 are bundled. Any unrelated procedure in that window needs modifier 79; a return to the OR for a complication related to the fusion requires modifier 78. Fluoroscopy used intraoperatively to confirm screw placement is integral to the arthroscopic procedure and is not separately billable under NCCI policy.

Site-of-service matters here: HOPD and ASC facility payments differ substantially (see the Site of Service comparison table). When performed bilaterally in a single session, bill on two lines with modifiers LT and RT in the ASC setting; hospital outpatient follows the single-line modifier 50 convention. If the procedure required significantly greater work than typical — for example, severe deformity, prior hardware removal, or complex bone grafting — document that additional work thoroughly and append modifier 22 with a supporting cover letter.

RVU & reimbursement

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

Source · CMS Physician Fee Schedule, RVU26A · January 2026

Work RVU	11.88
Practice expense RVU	10.14
Malpractice RVU	2.53
Total RVU	24.55
Medicare national rate	$819.99
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	$819.99
HOPD (APC 5115) Hospital outpatient department	$13,116.76
ASC (PI J8) Ambulatory surgical center (freestanding)	$9,799.32

Common denial reasons

The recurring reasons claims for CPT 29907 get rejected.

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

Operative note lacks arthroscopic technique specifics, triggering downcoding to a lesser arthroscopy code
Fluoroscopy or C-arm use billed separately — it is integral to the arthroscopic procedure and bundled under NCCI
Modifier 50 used in the ASC setting instead of separate LT/RT lines, causing claim adjudication failure
Bone graft harvesting billed separately without documentation that it was performed at a distinct anatomic site
Post-op office visits billed without a modifier during the 90-day global period, leading to automatic denial

Frequently asked questions

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

01Is fluoroscopy separately billable when used during CPT 29907?

No. Per NCCI policy, fluoroscopy performed during an arthroscopic procedure is integral to the arthroscopy and cannot be billed separately. Do not append a fluoroscopy code to the claim.

02Can bone graft harvesting be billed separately with 29907?

Only if the graft was harvested from a clearly distinct anatomic site with its own incision and documented separately in the operative note. Graft prep from the local arthroscopic site is bundled. Use a modifier 59 or XS with thorough documentation if billing a separate harvest code.

03How do you bill 29907 when performed on both feet in the same session?

In the ASC, bill two lines: one with modifier LT and one with RT, each with one unit. In the hospital outpatient setting, bill one line with modifier 50. Do not use modifier 50 in the ASC — it will misadjudicate.

04What modifier applies if the patient returns to the OR during the 90-day global for a wound complication from the fusion?

Modifier 78 — unplanned return to the OR for a related procedure during the global period. Do not use modifier 79, which is reserved for procedures unrelated to the original surgery.

05When is modifier 22 appropriate for CPT 29907?

When the procedure required substantially more work than a typical subtalar arthrodesis — for example, severe valgus or varus deformity, prior failed hardware removal, or extensive bone loss requiring complex grafting. The operative note must describe the specific findings and extra work performed. Attach a cover letter with the claim.

06Does CPT 29907 have a global period, and what does it cover?

Yes — 90-day global. That includes the surgery day, the day-before pre-op visit, and all routine follow-up through day 90: office visits, wound checks, cast or boot changes, and suture removal. Anything outside routine post-op care, or care for an unrelated condition, needs modifier 24 or 79 respectively.

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 arthroscopic portal placement, cartilage preparation technique, bone graft source and placement details, and fixation hardware specifics directly from surgeon dictation. It flags when the operative note lacks the arthroscopic approach language that distinguishes 29907 from open fusion codes — preventing the most common audit flag for this procedure. If the surgeon dictates unusual complexity, the scribe surfaces a modifier 22 prompt automatically.

See how Mira captures CPT 29907 documentation