Surgical tenotomy, lengthening, or release of the abductor hallucis muscle at the big toe, performed to correct deformity or relieve pain and restore function.

Verified May 8, 2026 · 6 sources ↓

Medicare: $440.22
Work RVU: 4.37
Global, days: 90
Region: Foot & ankle

Drawn from CMSAAPCFindacodeNIHMdclarity

Documentation requirements

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

Source · Editorial brief grounded in 6 cited references ↓

Specify the exact technique performed: tenotomy, fractional lengthening, or full release of the abductor hallucis muscle.
Document the laterality (left vs. right foot) explicitly in the operative note.
Record the pre-operative diagnosis with supporting clinical findings — imaging (X-ray, MRI) and physical exam demonstrating deformity or functional limitation.
If performed alongside another foot procedure, document the independent medical necessity and distinct anatomic work justifying separate billing.
Note anesthesia type administered and patient positioning used during the procedure.
Include post-operative plan, weight-bearing status, and dressing applied to support medical necessity and global period management.

Applicable modifiers

Modifiers commonly billed with this code.

Source · AMA CPT modifier descriptors · CMS NCCI Policy Manual

22 Increased complexity 24 Unrelated E/M during global 50 Bilateral procedure 51 Multiple procedures 59 Distinct service 78 Unplanned return — related 79 Unrelated during global LT Left side RT Right side

What this code covers

Source · Editorial summary grounded in 6 cited references ↓

CPT 28240 covers surgical tenotomy, lengthening, or release of the abductor hallucis muscle — the primary soft-tissue procedure targeting the medial musculature of the hallux. It is most commonly performed for hallux valgus correction, flatfoot-related medial tension, or functional deformity where the abductor hallucis is contributing to malalignment or pain. The procedure involves a targeted incision over the medial foot, isolation of the abductor hallucis, and either transection, fractional lengthening, or full release depending on intraoperative findings.

The 90-day global period governs all routine post-op care, casting checks, wound management, and suture removal through day 90. Any E/M visit during that window for an unrelated condition requires modifier 24; a distinct same-day procedure requires modifier 59 or an X-modifier. When bundled alongside a bunionectomy or MTP capsulotomy on the same foot, NCCI edits are in play — code 28240 is frequently a component procedure and may not be separately reportable without a supported modifier and documentation of independent work.

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 (4.37) is the surgeon's own effort — the figure physician pay and productivity targets are built on. The total RVU (13.18) adds practice overhead and malpractice, and is what drives the Medicare payment below.

Work RVU	4.37
Practice expense RVU	8.37
Malpractice RVU	0.44
Total RVU	13.18
Medicare national rate	$440.22
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	$440.22
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 28240 get rejected.

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

Bundling denial when billed alongside bunionectomy (28290–28299) without a supported modifier — NCCI edits frequently bundle 28240 as a component.
Missing laterality modifier (LT or RT) causes claim rejection or payer-specific denial on lateralized procedures.
Inadequate medical necessity documentation — no imaging, clinical exam findings, or conservative treatment failure noted in the record.
Upcoding flags when the operative note describes a minimal release but the claim is billed with modifier 22 without documentation of extraordinary work.
Global period violation — separate billing for routine post-op visits within the 90-day window without modifier 24 or 79.

Frequently asked questions

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

01Is 28240 commonly bundled with bunionectomy codes?

Yes. NCCI edits bundle 28240 into several bunionectomy codes (28290–28299). If the abductor hallucis release represents distinct, separately documented work, modifier 59 may support unbundling — but the operative note must clearly describe independent anatomic work and medical necessity beyond the bunionectomy itself.

02Can 28240 be billed bilaterally in the same session?

Yes. Use modifier 50 for a true bilateral procedure performed in the same operative session. Alternatively, append LT and RT to separate line items per payer preference. Confirm bilateral policy with the specific payer before claim submission, as some require modifier 50 on one line and others require two lines.

03What is the global period for 28240 and what does it include?

28240 carries a 90-day global period. That covers the day before surgery, the procedure day, and all routine post-operative care through day 90 — including wound checks, dressing changes, and suture removal. Unrelated E/M visits within the window need modifier 24. A return to the OR for a related complication requires modifier 78.

04What ICD-10 diagnoses are most appropriate to pair with 28240?

Hallux valgus (M20.1x), acquired deformities of the toe (M20.5x), and flatfoot-related conditions (M21.4x) are common supporting diagnoses. The specific ICD-10 code must match the clinical indication documented — a mismatch between diagnosis and procedure is a top denial driver.

05Can 28240 be billed with MTP capsulotomy (28270) on the same date?

Potentially, but NCCI edits apply. The capsulotomy code 28270 and 28240 may be bundled depending on the specific toe and payer rules. If both represent distinct, separately documented procedures on different anatomic structures or different toes, modifier 59 with strong operative note support may allow separate billing. Verify current NCCI edits before submitting.

06Does the site of service affect reimbursement for 28240?

Yes. Medicare payment differs between the hospital outpatient department (HOPD) and the ambulatory surgery center (ASC). The ASC rate is lower than the HOPD rate — see the site of service comparison table for current 2026 figures. Physician work RVUs remain the same regardless of setting, but the facility component varies significantly.

Sources & references

Editorial content was developed using the following public sources. Last verified May 8, 2026.

Mira Scribe

Mira's AI scribe captures the specific technique (tenotomy vs. lengthening vs. full release), the muscle and anatomic approach documented in the dictation, and explicit laterality from the operative note. This prevents the two most common audit flags for 28240: vague operative notes that say 'soft tissue release' without naming the abductor hallucis, and laterality omissions that trigger claim rejections before adjudication.

See how Mira captures CPT 28240 documentation