CPT code 28750: Arthrodesis, great toe metatarsophalangeal joint

CPT code 28750 is the procedure code for arthrodesis of the great toe at the metatarsophalangeal (MTP) joint. It covers surgical fusion of the first MTP joint to correct hallux rigidus and severe hallux valgus. Podiatric and orthopedic practices billing this code face a specific set of documentation and modifier decisions that directly affect reimbursement.

The code is maintained by the American Medical Association (AMA), which publishes the descriptor that defines what 28750 may be reported for. This guide covers that descriptor, the clinical indications, the ICD-10 crosswalk, and the modifiers. It also covers 2026 Medicare fee schedule and RVU figures, plus the documentation payers expect.

Key takeaways

CPT code 28750 describes surgical fusion of the great toe MTP joint, distinct from interphalangeal joint fusion (CPT 28760).

Primary ICD-10 indications are hallux rigidus (M20.20-M20.22) and hallux valgus (M20.10-M20.12), coded to the operated side.

Modifier 50 covers bilateral procedures, but some payers want separate LT and RT lines instead, so check the policy first.

The 2026 work RVU is 8.75, and the 90-day global period bundles routine follow-up visits into the surgical payment.

Pabau’s claims management software supports coding accuracy and clean claim submission for foot and ankle surgery practices.

What is CPT code 28750?

CPT code 28750 is the billing code for arthrodesis of the great toe at the metatarsophalangeal joint, as defined in the AMA’s Current Procedural Terminology. The official descriptor reads: Arthrodesis, great toe; metatarsophalangeal joint. This is a Category I CPT code that falls within the musculoskeletal surgery section covering foot and ankle procedures.

The procedure involves surgically fusing the first metatarsal head to the proximal phalanx of the great toe, eliminating motion at that joint. Surgeons typically use internal fixation hardware (plates, screws, or crossed screws) to hold the bones in the corrected position while fusion occurs. CPT 28750 captures only the MTP joint fusion; interphalangeal joint fusion is reported separately under CPT 28760.

Clinical indications for CPT 28750

First MTP joint arthrodesis is indicated when conservative treatment fails to relieve pain or correct deformity. Payers expect documentation showing that non-surgical options were tried and failed. Orthotics, corticosteroid injections, physical therapy, and shoe modification all count toward that history.

The two primary diagnoses driving billing for CPT 28750 are hallux rigidus and severe hallux valgus. Hallux rigidus involves progressive cartilage loss and osteophyte formation at the MTP joint that restricts dorsiflexion; end-stage cases cause significant functional impairment. Severe hallux valgus with a high intermetatarsal angle that is not amenable to osteotomy correction is another common indication, particularly in revision cases.

• Hallux rigidus (end-stage): Grade III or Grade IV, with joint space obliteration on imaging
• Severe hallux valgus: Intermetatarsal angle too large for osteotomy or failed prior correction
• Hallux valgus with arthritis: MTP joint degeneration alongside angular deformity
• Rheumatoid arthritis affecting the MTP joint: With joint destruction and progressive deformity
• Failed prior MTP surgery: Revision arthrodesis following failed bunionectomy or previous implant
• Traumatic arthritis: Post-fracture joint destruction at the first MTP level

When the intermetatarsal angle still allows correction without fusion, an osteotomy code applies instead. CPT 28298 reports hallux valgus correction with a proximal phalanx osteotomy, often called an Akin osteotomy.

Performed on its own, without a bunionectomy on the same claim, the Akin is reported with CPT 28310 instead. The code carries a separate procedure designation, so it bundles into a more comprehensive foot procedure at the same site.

ICD-10 codes commonly paired with CPT 28750

These ICD-10-CM codes are commonly documented alongside CPT 28750 to establish medical necessity. Payers match the diagnosis to the procedure, and a non-specific code is a common reason for denial. Use laterality-specific codes wherever the operative record supports them. The supporting diagnosis comes from the ICD-10-CM code set, not from an unspecified default.

Modifiers for CPT code 28750

Modifier selection for CPT 28750 depends on the operative site (right, left, or bilateral) and any circumstances affecting complexity. Incorrect modifier use is one of the top causes of claim rejection for foot surgery codes. Confirm modifier policies with each payer’s local coverage determination (LCD) before submitting, as rules on bilateral reporting in particular vary.

2026 Medicare fee schedule for CPT 28750

Medicare reimbursement for CPT 28750 varies by geographic location, and the figures below represent national averages based on the 2026 Medicare Physician Fee Schedule. Use the CMS Physician Fee Schedule Look-Up Tool to obtain your practice’s locality-adjusted rates. The geographic practice cost index (GPCI) affects all three RVU components. Rates are also different in facility settings (hospital outpatient department or ASC) versus non-facility (office) settings.

Important: The figures above are estimates drawn from published fee schedule data. Verify them against the official CMS MPFS for your locality and the applicable year. Private payer rates vary substantially and may sit above or below Medicare. On a surgical claim of this size, one missing modifier costs more than a full day of office visits.

RVU breakdown for CPT 28750

Relative value units (RVUs) quantify the physician work, practice expense, and malpractice components that together determine Medicare payment. CMS finalized a 2026 work RVU of 8.75 for CPT 28750, up from 8.57 in 2025. The code carries a 90-day global surgery period.

The work RVU covers surgeon time and cognitive effort, and it does not change with the setting. The practice expense RVU is the component that moves, because office overhead is carried by the practice and hospital overhead is not.

The table below splits the total into its three components for each setting.

Practice expense and malpractice figures are approximate and should be confirmed against the CMS Physician Fee Schedule for your locality. The 90-day global period bundles routine follow-up visits into the 28750 payment. Billing an evaluation and management code inside that window requires modifier 24, which tells the payer the visit was unrelated to the surgery.

Documentation requirements for CPT 28750

Thorough documentation is the front line against claim denial and audit exposure. Payers look for evidence of medical necessity and operative specificity. The operative report has to describe what was done at that joint, in that patient, rather than repeat a stock fusion narrative. The record for 28750 should contain each element below.

• Conservative treatment history: Documentation showing orthotics, injections, physical therapy, or shoe modification were attempted and failed
• Pre-operative imaging: Weight-bearing X-rays confirming joint space loss, osteophyte formation, or angular deformity
• Operative report specifics: Patient positioning, approach used (dorsal, medial), type of fixation (plate, screws, crossed K-wires), bone preparation technique, and the joint level fused
• Intraoperative findings: Description of cartilage status, osteophyte size, and any bone grafting performed
• Position of fusion: Stated degrees of hallux dorsiflexion and valgus angle at time of fixation
• Diagnosis linkage: The operative report diagnosis must align with the ICD-10-CM code reported on the claim
• Laterality: Clearly documented right, left, or bilateral

Some payers require prior authorization for elective foot arthrodesis. Confirm authorization requirements before scheduling the procedure, as retro-authorization is not always granted. General documentation guidance applies; always consult the individual payer’s LCD for CPT 28750 to confirm their specific requirements.

Billing guidelines and common coding errors for CPT 28750

Foot surgery coding has predictable error patterns, most of them created by bundling rules and bilateral billing. The issues below are the most common sources of claim denial on CPT 28750 submissions.

• Billing 28750 and 28760 together without a modifier: MTP joint fusion (28750) and interphalangeal joint fusion (28760) can be performed at the same session. Most payers still apply bundling edits. Report both with modifier 59 on the lesser procedure to indicate distinct procedural services, and ensure the operative report documents both joint levels.
• Missing bilateral modifier: When both feet are operated on, the claim must include modifier 50 (or separate LT/RT lines, depending on the payer). Submitting 28750 on a single line without a bilateral indicator typically results in payment for one side only.
• Non-specific ICD-10 code: Submitting M20.10 (unspecified foot) when the record documents a side loses specificity. Some payers flag it for medical review.
• Unbundling incidental procedures: Bone grafting performed as part of the fusion is typically included in 28750. Billing a separate bone graft code may trigger an NCCI edit rejection.
• E/M visits during the global period: Follow-up visits in the 90-day window require modifier 24 when unrelated. A new unrelated procedure takes modifier 79, and routine post-op care is not separately billable.

Tracking denial codes after 28750 submissions shows which error patterns recur in your practice. CO-4 means the procedure code is inconsistent with the modifier, and CO-97 means payment is included in another service.

CO-197 is the code tied to missing or absent prior authorization. CO-57 is a separate problem, since it means the payer considers the submitted information insufficient to support that level of service. A clean claim passes every payer edit on first submission, and complete documentation is what gets it there.

CPT 28750 vs CPT 28760: Key differences

CPT 28750 and CPT 28760 are two distinct arthrodesis codes for the great toe, differing by which joint is fused. Auditors look for operative report language that names the joint level, so the wrong choice surfaces on review rather than at submission.

Paired codes do not always divide on anatomy. HCPCS code J2710 and J2711 separate by drug product rather than dose, since J2711 covers neostigmine methylsulfate combined with glycopyrrolate.

Related CPT codes for great toe and foot arthrodesis

CPT 28750 sits within a family of foot and ankle codes used to capture related procedures. When multiple procedures are performed at the same operative session, each must be reported separately with appropriate modifiers.

The table below shows the codes most frequently referenced alongside 28750, including related foot arthrodesis codes and hallux correction procedures. Reporting more than one of them together calls for a payer-specific review of NCCI edits.

The official descriptor for CPT 28270 ends with the parenthetical separate procedure. That wording decides whether the capsulotomy is reported on its own or absorbed by a more comprehensive procedure at the same joint.

How practice management software supports CPT 28750 billing

Podiatric and orthopedic practices billing high-value surgical codes like CPT 28750 depend on claims management software. It validates code combinations, modifier logic, and diagnosis linkage before a claim leaves the practice. Reviewing each surgical encounter by hand is slow and error-prone, especially when several codes are reported in one session.

Pabau, practice management software built for medical and aesthetic practices, integrates with Claim.MD. That clearinghouse connects to over 4,000 US payers. A 28750 claim routes electronically, eligibility checks confirm patient coverage before surgery, and remittances post against the claim after payment.

Your billing team sees which foot arthrodesis claims were paid, adjusted, or denied, and can open the denial code without switching systems. Denial patterns by payer then surface early enough to change the next authorization request.

Streamline your foot surgery billing with Pabau

Pabau’s claims management tools help podiatric and orthopedic practices submit accurate claims for surgical codes like CPT 28750. Track denials by code and reconcile remittances automatically.

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Conclusion

Three things decide whether a 28750 claim is paid. The operative report must name the joint level. The modifier must carry the correct laterality, and the ICD-10 code must support medical necessity. Get one wrong and the claim comes back on a procedure worth several hundred dollars a side.

The 2026 work RVU rose to 8.75, so the claim is worth marginally more than last year. That makes no difference if it denies. The authorization check and the modifier belong in the pre-surgical workflow, not in the billing queue.

Pabau’s claims management tools help podiatric and orthopedic practices submit 28750 claims accurately, track remittances by code, and clear denials before they age. Book a demo to see how the surgical billing workflow runs end to end.

Continue your research

Want to understand how clearinghouse claims routing works? Medical claims clearinghouse guide explains how electronic claims move from practice to payer and where errors get caught.

Need to track denial patterns across surgical codes? Denial management in healthcare covers how to categorise, appeal, and reduce claim denials systematically.

Looking for guidance on ERA remittance reconciliation? Medical superbill guide walks through how superbills connect to clearinghouse submissions and ERA matching.

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