CPT code 28292 – Hallux valgus correction with proximal phalanx base resection

Key takeaways

CPT code 28292 reports a Keller-type bunionectomy, where the surgeon resects the base of the big toe’s proximal phalanx.

No metatarsal osteotomy belongs in 28292. Chevron, Lapidus, Akin, and double osteotomy corrections each have their own code.

Sesamoidectomy is “when performed” in 28292 and in 28295 through 28299, so it never decides between them.

The code carries a 90-day global period, so separate post-op services need modifier 24, 58, 78, or 79.

Pair it with M20.11 or M20.12, and make the side match the operative note and any side modifier.

CPT code 28292 names one bunion technique

CPT code 28292 reports hallux valgus correction (bunionectomy) with resection of the proximal phalanx base, when performed, by any method. Surgeons still call it the Keller procedure. The surgeon removes the base of the big toe’s first bone, which decompresses the joint and lets the toe settle straighter.

The full descriptor also says “with sesamoidectomy, when performed.” That clause appears in every sibling code, so it tells you nothing about which one to pick. The AMA’s CPT code set removed eponyms like Keller from these descriptors in 2017. The technique stayed, now described in plain anatomical terms.

What sets 28292 apart is the bone it cuts. The work happens on the phalanx, and the first metatarsal is not cut. Keller-type resection is usually reserved for older, lower-demand patients or salvage cases.

The operative note picks the code for you

Coders choose 28292 from the technique the surgeon documents. Complexity, time, and the bunion’s severity do not change the code. So before you assign it, find these points in the note:

• Diagnosis and side: hallux valgus, with right or left foot stated in the header and the procedure narrative.
• The resection: excision of the proximal phalanx base, with the amount of bone removed.
• Joint work: capsule handling, soft tissue balancing, and any medial eminence removal.
• Sesamoid work, if any: sesamoid excision is allowed in 28292, but its absence does not change the code.
• Fixation: any temporary wire used to hold the toe while the joint heals.

Now look for what should not be there. A named metatarsal cut, such as a chevron or a basal osteotomy, points to another code. The same goes for a fusion of the first metatarsal and medial cuneiform. In those cases, 28292 is the wrong choice, however the note is titled.

Six codes share one descriptor, and the bone splits them

Each of the six codes (28292 and 28295 through 28299) starts with the same hallux valgus wording. From there, each descriptor names a different primary technique, so the bone work in the note picks the code.

The decision path below starts from that bone.

The table adds what sets each sibling apart from 28292.

Sesamoidectomy appears as “when performed” in all six codes. It can’t move a claim from one code to another.

The phalanx can mislead too. An Akin osteotomy cuts it without resecting the base, so that case goes to 28298. If the diagnosis is hallux rigidus rather than hallux valgus, review 28289 and 28291 before you settle on a code.

Laterality starts with the diagnosis code

Payers check that the diagnosis side, the modifier, and the operative note agree. A right-foot procedure billed with a left-foot code is an easy denial.

Lead with M20.11 or M20.12 whenever the note supports it. The bunion codes add detail, but some payer policies won’t accept them alone for medical necessity.

Medicare values 28292 at 13.77 facility RVUs

Medicare prices 28292 with relative value units (RVUs) from the Physician Fee Schedule. The 2026 figures below use the $33.4009 conversion factor, before any locality adjustment. Confirm current values in the CMS Physician Fee Schedule lookup.

Those national figures are starting points. Your Medicare Administrative Contractor (MAC) locality shifts them up or down, and commercial contracts set their own rates.

Modifiers carry the side and the global period

Most 28292 modifier questions fall into two groups. Some modifiers tell the payer which foot or toe was treated. Others explain a service that lands inside the 90-day global period.

Some codes never ride alongside 28292

The National Correct Coding Initiative (NCCI) pairs 28292 with codes that it already includes. Edits change every quarter, so check the current CMS NCCI edit tables before each unusual claim.

• Sesamoidectomy (28315): sesamoid work is in the 28292 descriptor, so don’t report it again.
• Proximal phalanx excision (28160): removing the phalanx base is the core of 28292, so a separate hemiphalangectomy duplicates it.
• Metatarsal head exostectomy (28288): medial eminence removal is part of the bunionectomy itself.
• A second hallux valgus code on the same foot: 28295 through 28299 are alternative primary codes. Check NCCI edits and payer policy before reporting two.
• Hammertoe correction (28285) on a lesser toe: often separately reportable with a toe modifier and its own diagnosis.

When you override an edit with 59 or XS, the note must separate the procedures clearly. Auditors look for overrides that the documentation does not support.

Ninety days of follow-up are already paid for

The 090 global period covers routine aftercare from the surgery date. Wound checks, dressing changes, suture or wire removal, and related visits are not billed separately. Our guide to medical billing basics explains how global payments fit the wider claim cycle.

• Modifier 24: an E/M visit for an unrelated problem during the global period.
• Modifier 58: a staged or planned related procedure, or a more extensive one.
• Modifier 78: an unplanned return to the operating room for a related complication.
• Modifier 79: an unrelated procedure during the global period.

For a bilateral case done in one session, both globals start on the same date. Post-op notes should still name the foot being managed.

Payers want proof that conservative care failed

Traditional Medicare does not usually require prior authorization for 28292. Medicare Advantage, Medicaid managed care, and commercial plans often do, so check each payer before booking surgery.

Strong medical billing compliance starts in the pre-op chart. Coverage policies commonly ask for:

• A documented trial of conservative care, such as wider footwear, padding, orthotics, or anti-inflammatory medication.
• Weight-bearing X-rays with the hallux valgus and intermetatarsal angles recorded.
• Pain or functional limits, such as trouble walking or wearing standard shoes.
• The surgeon’s statement that surgery is now medically necessary.

Required thresholds and timeframes vary by payer. Read the policy that applies to each patient instead of relying on a single rule of thumb.

Common mistakes that sink a 28292 claim

Most 28292 denials repeat the same few errors. Good denial management fixes the cause at coding, not at appeal.

Track your denial codes by reason. Patterns show whether coding, documentation, or authorization needs attention.

Before you submit: A 28292 checklist

Run through this list before releasing a clean claim for 28292.

• The note documents resection of the proximal phalanx base.
• No metatarsal osteotomy or Lapidus fusion is described for this foot.
• The diagnosis is M20.11 or M20.12, matching the operative side.
• The side modifier (RT/LT or TA/T5) follows this payer’s policy.
• Bilateral cases follow the PFS bilateral indicator and payer rules.
• No bundled code, such as 28315 or 28160, is listed separately.
• Any 59 or XS override has a distinct site in the note.
• Conservative care, X-ray angles, and functional limits are in the pre-op chart.
• The prior authorization number is on the claim, where required.

How Pabau keeps 28292 claims moving

Coders still decide between 28292 and its siblings, so that judgment stays with your team. The slower work comes after coding, when staff check coverage, send the claim, and match payments.

Pabau, the practice management platform we build, handles that stretch with its end-to-end claims management. In the US, it submits claims through the Claim.MD clearinghouse, checks patient eligibility, and posts 835 electronic remittances. The code you assign, the patient record, and the payment then sit in one place.

Get podiatry claims out the door faster

Pabau submits claims through Claim.MD, runs eligibility checks, and posts 835 remittances, so your team spends less time chasing bunionectomy payments.

Book a demo

Conclusion

Code 28292 only when the note describes a resection of the proximal phalanx base. If the surgeon cut or fused the metatarsal, or cut the phalanx without resecting its base, a sibling code fits better. Sesamoid work and case difficulty won’t settle the choice either way.

Build that check into your coding routine, and many avoidable 28292 denials never reach your desk. Book a demo to see how Pabau helps podiatry teams submit and track surgical claims.

Continue your research

Need to understand the claims submission workflow? Claim.MD clearinghouse overview explains how electronic claim submission works end-to-end for US medical practices.

Tracking remittances after 28292 claims pay? Electronic remittance advice guide covers how to read and reconcile 835 ERA files from Medicare and commercial payers.

Want to reduce revenue cycle delays? Revenue cycle management fundamentals walks through the full claim lifecycle from eligibility through payment posting.

Did the note describe two bone cuts? CPT code 28299 billing guide covers double osteotomy bunion correction and how it differs from 28292.

Treating a bunionette rather than a bunion? CPT code 28110 billing guide explains coding for the fifth metatarsal head ostectomy.

Frequently asked questions about CPT code 28292