Osteotomy of a phalanx in any toe except the proximal phalanx of the great toe, performed to correct shortening, angular, or rotational deformity.

Verified May 8, 2026 · 8 sources ↓

Medicare: $595.87
Work RVU: 4.57
Global, days: 90
Region: Foot & ankle

Drawn from CMSMdclarityAAPCCgsmedicareGenhealth

Documentation requirements

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

Source · Editorial brief grounded in 8 cited references ↓

Specify which toe and which phalanx was osteotomized (e.g., middle phalanx, second toe, right foot)
Document the deformity type corrected: shortening, angular malalignment, or rotational — not just 'toe deformity'
Confirm the operative note excludes the proximal phalanx of the great toe; if that bone was addressed, code 28310 applies instead
Record the osteotomy technique used (e.g., closing wedge, opening wedge, step-cut) — audit teams flag notes that only state 'osteotomy performed'
If revision surgery, document what the original procedure was, when it was performed, and the clinical reason revision was necessary
Include preoperative imaging or clinical findings confirming the structural deformity warranting surgical correction

Applicable modifiers

Modifiers commonly billed with this code.

Source · AMA CPT modifier descriptors · CMS NCCI Policy Manual

22 Increased complexity 51 Multiple procedures 58 Staged or related 59 Distinct service 76 Repeat, same 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 8 cited references ↓

CPT 28312 covers a phalangeal osteotomy — cutting and repositioning bone — on any toe except the proximal phalanx of the first (great) toe, which falls under 28310. The procedure corrects shortening, angular malalignment, or rotational deformity of lesser toe phalanges, and may be performed as a primary correction or as a revision following a failed prior surgery. Wedge osteotomies of the interphalangeal joint of the toe are a recognized use of this code; coders who reach for 28124 (partial phalangectomy) for that scenario are miscoding.

The 90-day global period means all routine post-op visits, wound checks, and dressing changes through day 90 are bundled. Any visit for an unrelated condition during that window requires modifier 24. If a complication requires an unplanned return to the OR, bill 28312 again with modifier 78. A staged or planned subsequent procedure in the global period uses modifier 58. When the same session includes additional distinct foot or toe procedures, list 28312 first (highest RVU), append modifier 51 to secondarily listed codes, and verify NCCI PTP edits before submitting.

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 (4.57) is the surgeon's own effort — the figure physician pay and productivity targets are built on. The total RVU (17.84) adds practice overhead and malpractice, and is what drives the Medicare payment below.

Work RVU	4.57
Practice expense RVU	12.55
Malpractice RVU	0.72
Total RVU	17.84
Medicare national rate	$595.87
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	$595.87
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 28312 get rejected.

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

Wrong code selected — 28124 (partial phalangectomy) used instead of 28312 for a wedge osteotomy of the interphalangeal joint
Missing laterality — claim submitted without LT or RT modifier, triggering payer edit for digit-level procedures
Global period conflict — post-op visit or secondary procedure billed without required modifier 24, 58, or 78 during the 90-day global
Insufficient operative documentation — note fails to identify the specific phalanx osteotomized or the deformity type corrected
NCCI PTP bundle — 28312 billed same-day with a column-1 comprehensive code without a clinically supported modifier 59 or XS

Frequently asked questions

Source · Generated from the editorial pipeline, verified against 8 cited references ↓

01What is the difference between CPT 28312 and 28310?

28310 covers an osteotomy of the proximal phalanx of the great (first) toe specifically. 28312 applies to any other phalanx in any toe. If your operative note documents the proximal phalanx of the great toe, use 28310, not 28312.

02Can 28312 be billed for a wedge osteotomy of the interphalangeal joint of a lesser toe?

Yes. A wedge osteotomy at the interphalangeal joint of a lesser toe maps to 28312. Code 28124 (partial phalangectomy) is not correct for that scenario — a common miscoding flagged in AAPC coding forums.

03Is modifier 50 appropriate if both feet are operated on during the same session?

Yes. If you perform a qualifying osteotomy on the same toe bilaterally in a single operative session, modifier 50 applies. Alternatively, some payers prefer separate line items with LT and RT — verify payer preference before submitting.

04What modifier applies if a complication requires the patient to return to the OR during the 90-day global?

Use modifier 78 for an unplanned return to the OR for a procedure related to the original surgery. If the return OR visit addresses an entirely unrelated condition, use modifier 79 instead. Do not invert these — modifier 78 is always the related complication return.

05If 28312 is performed alongside another foot procedure on the same day, how should the claim be structured?

List the code with the highest RVU in the primary position. Append modifier 51 to 28312 if it is the secondary procedure. Check NCCI PTP edits for the specific code pair — some combinations require modifier 59 or XS to bypass a bundle, and others are not bypassable at all.

06Does 28312 carry a global period, and what does that mean for post-op billing?

28312 has a 90-day global period under CMS. All routine follow-up visits, wound checks, suture removals, and dressing changes through day 90 are bundled into the surgical fee. Visits for unrelated conditions during that window require modifier 24; staged subsequent procedures require modifier 58.

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 toe, phalanx, and foot side from dictation, along with the deformity type (angular, rotational, or shortening) and the osteotomy technique performed. It also flags when a proximal phalanx of the great toe is mentioned — a signal that 28310 may apply instead of 28312 — preventing a miscoded claim before it reaches the biller.

See how Mira captures CPT 28312 documentation