Surgical correction of hallux valgus (bunion) using a double osteotomy technique, with bunionectomy and sesamoidectomy when performed.

Verified May 8, 2026 · 6 sources ↓

Medicare: $1,036.43
Total RVUs: 31.03
Global, days: 90
Region: Foot & ankle

Drawn from CMSAAPCPayerpriceMdclarityFindacode

Documentation requirements

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

Source · Editorial brief grounded in 6 cited references ↓

Preoperative weight-bearing radiographs documenting the hallux valgus angle (HVA) and intermetatarsal angle (IMA)
Operative note identifying both osteotomy sites by location and method (e.g., proximal + distal, chevron + Akin)
Explicit documentation of why double osteotomy was required — degree of deformity and inadequacy of a single-cut correction
Notation of sesamoidectomy if performed, including which sesamoid and the clinical indication
Laterality clearly documented (left foot, right foot, or bilateral) to support LT/RT/50 modifier use
Conservative treatment failure documented prior to surgery (orthotics, shoe modification, injections) to support medical necessity

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 52 Reduced services 59 Distinct service LT Left side RT Right side 78 Unplanned return — related 79 Unrelated during global 80 Assistant surgeon 24 Unrelated E/M during global 25 Significant separate E/M 57 Decision for surgery 58 Staged or related

What this code covers

Source · Editorial summary grounded in 6 cited references ↓

CPT 28299 covers hallux valgus correction performed via double osteotomy — meaning two bone cuts are made to realign the first ray. The procedure includes bunionectomy (removal of the bony prominence) and sesamoidectomy when indicated. It sits at the more technically demanding end of the bunion correction code family (28292–28299), used when a single osteotomy is insufficient to achieve adequate correction of the intermetatarsal angle and toe alignment.

The 90-day global period means all routine post-op visits, wound checks, cast changes, and hardware monitoring through day 90 are bundled. Anything unrelated to the bunion correction billed during that window requires modifier 24 (E/M) or 79 (unrelated procedure). A same-day E/M is only separately billable with modifier 25 if a distinct, separately documented decision was made beyond the decision for surgery itself.

Payers occasionally challenge whether a double osteotomy was truly necessary versus a single distal or proximal cut (28296 or 28298). Operative notes must document the rationale for two osteotomies — specifically the degree of deformity, intermetatarsal angle, and why a single osteotomy would not achieve adequate correction. Without that justification, expect downcoding to 28296.

RVU & reimbursement

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

Source · CMS Physician Fee Schedule, RVU26A · January 2026

Work RVU	9.06
Practice expense RVU	20.84
Malpractice RVU	1.13
Total RVU	31.03
Medicare national rate	$1,036.43
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	$1,036.43
HOPD (APC 5114) Hospital outpatient department	$7,413.38
ASC (PI J8) Ambulatory surgical center (freestanding)	$4,751.04

Common denial reasons

The recurring reasons claims for CPT 28299 get rejected.

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

Downcoded to 28296 or 28298 when operative note fails to justify why two osteotomies were required over one
Missing or insufficient preoperative imaging to document severity of deformity and support double osteotomy selection
Laterality modifier absent, causing claim to reject or pend for clarification
Global period violation — routine post-op services billed separately without appropriate modifier (24, 78, or 79)
Medical necessity denial when conservative treatment failure is not documented in the pre-surgical record

Frequently asked questions

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

01What separates 28299 from 28296 and 28298?

28296 uses a single distal metatarsal osteotomy. 28298 uses a single proximal phalanx osteotomy. 28299 requires two osteotomies — typically one in the metatarsal and one in the phalanx (or two metatarsal cuts). If your operative note only documents one bone cut, you're in 28296 or 28298 territory, not 28299.

02Is sesamoidectomy always included in 28299?

Sesamoidectomy is included when performed — it's not a required component. If you remove a sesamoid, note which one and the indication. Do not separately bill a sesamoidectomy code alongside 28299; it's captured within this procedure when done at the same operative session.

03Can 28299 be billed bilaterally?

Yes. Use modifier 50 if both feet are corrected in the same session, or LT and RT on separate line items per payer preference. Bilateral billing requires independent documentation of deformity and surgical rationale for each foot. Some payers reduce payment on the second side — check your contract.

04What modifiers apply if the patient returns to the OR during the 90-day global?

Use modifier 78 for an unplanned return to the OR for a complication or related procedure (e.g., hardware revision, wound dehiscence requiring OR management). Use modifier 79 for an unrelated procedure performed by the same surgeon during the global period. Do not use 78 for unrelated work — that's a common audit flag.

05Does a same-day E/M require a modifier when 28299 is also billed?

Only if the E/M reflects a separately identifiable decision beyond the decision to perform the bunion surgery. If the visit was the surgical decision visit (the day of or day before), bill modifier 57 on the E/M. If the E/M was for a genuinely distinct problem, use modifier 25. Without one of these, the E/M will bundle.

06What ICD-10 codes support medical necessity for 28299?

M20.11 (hallux valgus, right foot) and M20.12 (hallux valgus, left foot) are the primary diagnoses. Document any associated conditions — M21.6x for acquired deformity, or pain codes — when clinically present. Payers expect the HVA and IMA to reflect surgical-grade deformity, so align your imaging findings with the diagnosis code chosen.

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 osteotomy techniques performed (e.g., proximal metatarsal + distal Akin), the degree of deformity documented on preoperative imaging, the clinical rationale for a double versus single osteotomy, sesamoidectomy performance and indication, and laterality. This directly prevents the most common denial pattern for 28299 — downcoding to 28296 because the operative note didn't justify two cuts.

See how Mira captures CPT 28299 documentation