Foot and Ankle CPT Coding for Orthopaedic Practices in 2026: Bunions, Ankle Fractures, and the New Plantar Fasciitis Codes

Foot and ankle CPT coding for orthopaedic practices comes down to five decisions: which hallux valgus code matches the osteotomy actually performed, whether an ankle fracture is bimalleolar or trimalleolar and whether the posterior lip was fixed, whether a ligament or Achilles repair is primary or secondary, whether an arthroscopy is separately reportable next to an open procedure on the same ankle, and whether the toe and foot anatomic modifiers are on the claim instead of modifier 59.

In 2026 there is a sixth decision that affects nearly every foot clinic: on October 1, 2026, plantar fasciitis moves out of M72.2 and into a new ICD-10-CM subcategory, M67.A0-, with right, left, and unspecified foot codes. Claims with dates of service on or after October 1 that still carry the old code will not process cleanly.

This guide walks through each decision using the AMA CPT code set, the 2026 NCCI Policy Manual, and CMS global surgery rules.

Why foot and ankle coding deserves its own playbook

Foot and ankle volume is high, the codes are granular, and several procedures are often billed on the same foot in one session. A bunion correction with a second toe hammertoe repair and a fifth toe bunionette is three coding decisions, each with its own bundling rules and anatomic modifiers.

It also attracts audit attention. In December 2025 the HHS Office of Inspector General reported that 49 of 100 sampled podiatrist claims for routine foot care billed with E/M services did not comply with Medicare requirements (report A-09-22-03011), and a companion audit found a 44 percent error rate on podiatrist E/M claims, with recommendations aimed at modifier 25 oversight (A-09-22-03012). Orthopaedic foot and ankle clinics bill many of the same codes.

Hallux valgus (bunion) correction: 28292 through 28299

The hallux valgus family was overhauled in CPT 2017, when several codes were deleted and eponyms like Keller, McBride, Mitchell, Chevron, and Lapidus were removed from descriptors. In the current code set, each code describes correction of hallux valgus with bunionectomy, with sesamoidectomy when performed, plus one defining procedure:

• 28292: with resection of proximal phalanx base
• 28295: with proximal metatarsal osteotomy, any method
• 28296: with distal metatarsal osteotomy, any method
• 28297: with first metatarsal and medial cuneiform joint arthrodesis (the Lapidus procedure)
• 28298: with proximal phalanx osteotomy, any method
• 28299: with double osteotomy, any method

Code selection is driven by the osteotomy or arthrodesis, not by the surgeon's preferred eponym. An operative note that says "modified Lapidus" without describing the first metatarsal cuneiform arthrodesis leaves the coder guessing. A note that describes a distal metatarsal osteotomy plus an Akin osteotomy of the proximal phalanx supports 28299, not 28296 plus a separate phalangeal osteotomy code.

What is already included

The bunion codes include removal of the medial eminence and osteophytes, arthrotomy, capsulotomy, tenotomy, tendon releases, internal fixation, bursa removal, and articular shaving at the first MTP joint. That means a capsulotomy (28270) or tenotomy (28230, 28234) at the first MTP joint should not be added.

The 2026 NCCI Policy Manual, Chapter IV, is explicit on the most common unbundling error: CPT codes 28288, 28306, 28307, 28310, and 28315 shall not be reported with bunionectomy codes 28291 through 28299 for procedures on the ipsilateral first toe or metatarsal. If your team is billing 28310 with modifier 59 on top of a bunion correction, that pattern will not survive review.

Diagnosis coding

Hallux valgus is M20.11 (right foot) or M20.12 (left foot). There is no bilateral code, so staged or bilateral corrections need a laterality specific diagnosis on each line. M20.10 (unspecified foot) should rarely appear on a surgical claim, since the operative note always documents the side.

Hammertoe correction and the toe modifiers

CPT 28285 describes correction of hammertoe (for example, interphalangeal fusion or partial or total phalangectomy). 28286 describes correction of a cock-up fifth toe with plastic skin closure. Per coding guidance drawing on CPT Assistant, extensor and flexor tenotomy and interphalangeal capsulotomy performed as part of the hammertoe correction are included, while an MTP capsulotomy (28270) for a distinct MTP deformity can be reported separately when documented.

The bigger revenue issue is modifiers. NCCI Chapter IV states that toe procedures should be reported with modifiers TA and T1 through T9, and many toe codes carry a medically unlikely edit of 1 per claim line. That MUE assumes the toe modifiers are used when the same procedure is performed on more than one toe. A claim for 28285 on the second and third toes without T1 and T2 (left foot) or T6 and T7 (right foot) looks like a duplicate.

CMS's April 2026 fact sheet on modifiers 59 and X{EPSU} reinforces this: modifier 59 or XS should only be used when the service cannot be described by one of the more specific anatomic modifiers, including RT, LT, FA, F1 to F9, TA, and T1 to T9.

Ankle fracture ORIF: getting the malleoli right

All of the open ankle fracture codes include internal fixation when performed. The descriptors are specific enough that the operative note should make code selection mechanical:

• 27766: open treatment of medial malleolus fracture
• 27769: open treatment of posterior malleolus fracture
• 27792: open treatment of distal fibular fracture (lateral malleolus)
• 27814: open treatment of bimalleolar ankle fracture (lateral and medial, lateral and posterior, or medial and posterior malleoli)
• 27822: open treatment of trimalleolar ankle fracture, medial and/or lateral malleolus, without fixation of posterior lip
• 27823: the same, with fixation of posterior lip

Two common errors are coding by the radiology report instead of the operative note, and missing the posterior lip distinction. A trimalleolar injury where the surgeon fixes the fibula and medial malleolus but treats the posterior fragment nonoperatively is 27822. If the posterior fragment is fixed, it is 27823. Reporting 27814 plus 27769 for a trimalleolar fixation is not how the code set is built.

Syndesmosis fixation

CPT 27829 describes open treatment of distal tibiofibular joint (syndesmosis) disruption, including internal fixation when performed. Coding guidance has long supported reporting it in addition to bimalleolar or trimalleolar ORIF when the syndesmotic disruption and its fixation are separately documented. Check the current NCCI edit pair and payer policy before applying a modifier, and make sure the note describes the stress test or intraoperative instability finding that justified fixation.

NCCI fracture rules that apply here

NCCI Chapter IV sets three rules worth building into your charge review. Closed, percutaneous, and open treatment codes for the same fracture are mutually exclusive. A failed closed reduction converted to open treatment is reported with the open code only. And ankle fracture repair codes are not reported with strapping codes such as 29581.

Achilles tendon and lateral ankle ligament repair

Achilles repair codes split on whether the repair is primary or secondary and whether a graft is used:

• 27650: primary repair, open or percutaneous, ruptured Achilles tendon
• 27652: primary repair with graft (includes obtaining graft)
• 27654: secondary repair, with or without graft

Lateral ankle ligament repairs follow the same primary versus secondary logic. 27695 is a primary repair of a disrupted collateral ligament, 27696 covers both collateral ligaments, and 27698 is a secondary repair (for example, Watson-Jones). Published coding guidance supports 27698 for a chronic instability Broström procedure, with 27695 or 27696 reserved for acute primary repairs. AAOS guidance notes that the Gould modification (retinacular advancement) is not reported separately.

A common documentation gap is chronicity. "Lateral ankle instability, Broström performed" does not tell a coder or an auditor whether this is a primary repair of an acute injury or a secondary reconstruction of chronic instability. One sentence in the history and one in the procedure description closes it.

Ankle arthroscopy with open procedures

The ankle arthroscopy codes run from 29891 to 29899:

• 29891: excision of osteochondral defect of talus and/or tibia, including drilling
• 29892: arthroscopically aided repair of large osteochondritis dissecans lesion, talar dome fracture, or tibial plafond fracture
• 29894: removal of loose or foreign body
• 29895: partial synovectomy
• 29897: limited debridement
• 29898: extensive debridement
• 29899: with ankle arthrodesis

NCCI Chapter IV sets the framework. Surgical arthroscopy includes diagnostic arthroscopy. An arthroscopy performed only to evaluate the surgical field before an open procedure is not separately reportable. An arthroscopy converted to an open procedure is reported with the open code only. And, with the exception of the knee and shoulder, arthroscopic debridement is not reported separately with another surgical arthroscopy on the same joint.

Published guidance supports reporting a therapeutic arthroscopy (for example, 29898 for extensive debridement of documented intra-articular pathology) with a lateral ligament repair when the work is distinct and documented, while a diagnostic look is not billable. The deciding factor is the operative note. Per CPT Assistant guidance, the distinction between limited and extensive debridement is also a documentation question, so "debridement performed" is not enough to support 29898.

Plantar fasciitis: new ICD-10-CM codes effective October 1, 2026

The FY2027 ICD-10-CM update, effective for dates of service on or after October 1, 2026, creates a dedicated plantar fasciitis subcategory under M67 and separates it from plantar fascial fibromatosis:

• M67.A01: plantar fasciitis, right foot
• M67.A02: plantar fasciitis, left foot
• M67.A09: plantar fasciitis, unspecified foot
• M72.20, M72.21, M72.22: plantar fascial fibromatosis, unspecified, right, and left foot

M72.2 itself is no longer a valid billable code after September 30, 2026. There is no grace period for ICD-10-CM updates. Code by date of service, which means claims for September visits billed in October still use M72.2, and October visits must use the new codes.

Plantar fasciitis is one of the highest volume diagnoses in a foot and ankle clinic, and it lives in EHR favorites lists, order sets, injection templates, and orthotic and physical therapy referrals. Every one of those needs updating before October 1.

On the procedure side, the codes are unchanged: 28008 (fasciotomy, foot and/or toe), 28060 and 28062 (partial and radical plantar fasciectomy), 29893 (endoscopic plantar fasciotomy), and 28890 (high energy extracorporeal shock wave involving the plantar fascia, requiring anesthesia other than local). Many payers still treat 28890 as investigational, so check policy and use an Advance Beneficiary Notice where appropriate for Medicare patients.

The AMA's CPT 2027 code set, released September 9, 2026 and effective January 1, 2027, does not include notable foot and ankle Category I changes, so the plantar fasciitis ICD-10 update is the main foot and ankle code change to prepare for this year.

Global periods and staged procedures

Most major foot and ankle procedures carry a 90 day global period under the Medicare Physician Fee Schedule: one day before surgery, the day of surgery, and 90 days after. Staging matters because bunion and hammertoe corrections on the opposite foot are often scheduled inside the first foot's global period.

Per the CMS Global Surgery Booklet, modifier 58 applies to a staged or planned procedure, a more extensive procedure, or therapy following a diagnostic procedure, and it starts a new global period. Modifier 79 applies to an unrelated procedure during the postoperative period and also starts a new global period. Modifier 78 applies to an unplanned return to the operating room for a related complication and does not start a new global.

For a planned second foot correction, the operative planning note from the first surgery should document that the second side is staged. That single sentence is what supports modifier 58 when the second claim is reviewed.

A quick foot and ankle claim checklist

• The bunion code matches the osteotomy or arthrodesis documented, and no ipsilateral first ray code from the NCCI exclusion list is added on top.
• Every toe procedure carries TA or T1 to T9, and modifier 59 is only used where no anatomic modifier fits.
• Ankle fracture codes reflect the operative note, including posterior lip fixation.
• Achilles and ligament repairs document primary versus secondary.
• Arthroscopy with an open procedure has distinct, documented intra-articular work.
• Plantar fasciitis diagnoses use M67.A0- for dates of service on or after October 1, 2026.
• Staged procedures inside a global period carry modifier 58 with a planning note to support it.

Frequently asked questions

What is the CPT code for a Lapidus bunionectomy?‍

CPT 28297 describes correction of hallux valgus with bunionectomy, with sesamoidectomy when performed, and first metatarsal and medial cuneiform joint arthrodesis. The operative note should describe the arthrodesis itself, not just the eponym.

Can I bill an Akin osteotomy (28310) with a bunion correction?‍

Not on the same first toe. The 2026 NCCI Policy Manual states that 28288, 28306, 28307, 28310, and 28315 shall not be reported with bunionectomy codes 28291 to 28299 on the ipsilateral first toe or metatarsal. A distal or proximal metatarsal osteotomy combined with a proximal phalanx osteotomy is reported with 28299, the double osteotomy code.

What is the difference between CPT 27822 and 27823?‍

Both describe open treatment of a trimalleolar ankle fracture. 27822 is used when the posterior lip is not fixed, and 27823 is used when the posterior lip is fixed. The operative note should state whether the posterior fragment was fixed and how.

What is the new ICD-10 code for plantar fasciitis in 2026?‍

For dates of service on or after October 1, 2026, plantar fasciitis is reported with M67.A01 (right foot), M67.A02 (left foot), or M67.A09 (unspecified foot). M72.2 is expanded into M72.20 to M72.22 for plantar fascial fibromatosis and is no longer billable as a standalone code.

Should I use modifier 59 or T modifiers for procedures on multiple toes?‍

Use the toe modifiers. NCCI directs that toe procedures be reported with TA and T1 to T9, and CMS guidance says modifier 59 or XS should only be used when no more specific anatomic modifier applies.

Is ankle arthroscopy billable with a Broström procedure?‍

A diagnostic arthroscopy is not. A therapeutic arthroscopy, such as extensive debridement of documented intra-articular pathology, may be reported when it is distinct from the ligament repair and clearly documented. Check the current NCCI edit pair and payer policy, and make sure the note supports the specific arthroscopy code.

Where automation fits

Every decision in this guide comes from information already in the operative note, and it is exactly the work that slips when a coder is clearing a surgical queue on deadline. Maia's Surgical AutoCoder reads the operative note inside the EHR and recommends CPT, ICD-10, and modifier combinations with the clinical justification attached, so bundling rules, toe modifiers, and date of service diagnosis changes are applied the same way on every chart. Maia integrates with athenahealth, eClinicalWorks, Epic, ModMed, NextGen, and Tebra, and is used by orthopaedic groups today.

See how Maia helps orthopaedic practices code better. Book a demo at usemaia.com.