CPT Code 11450: Axillary hidradenitis excision billing guide

Key Takeaways

CPT Code 11450 covers excision of skin and subcutaneous tissue for axillary hidradenitis with simple or intermediate repair, used by dermatologists and surgeons treating hidradenitis suppurativa (HS).

The primary paired ICD-10-CM diagnosis code is L73.2, and 2026 Medicare reimbursement varies by geographic locality and place of service (facility vs. non-facility).

Modifier 50 applies when the procedure is performed bilaterally, and missing documentation of the repair type or anatomical site is the most common reason for claim denial.

Pabau’s claims management software gives dermatology and surgical practices one system to submit, track, and reconcile CPT 11450 claims, cutting down the manual work behind clean billing.

CPT Code 11450 is the code for excision of skin and subcutaneous tissue for hidradenitis in the axillary region, with simple or intermediate repair included. It is the code dermatologists and surgeons use when a patient with hidradenitis suppurativa (HS) needs surgical excision after conservative treatment has failed.

HS affects roughly 1% of the population worldwide, according to a JAMA Dermatology study. This guide covers the 2026 fee schedule, RVU components, ICD-10-CM pairings, modifiers, and documentation requirements for CPT Code 11450, along with the billing errors that most often trigger denials.

CPT Code 11450: definition and clinical description

Official description: Excision of skin and subcutaneous tissue for hidradenitis, axillary; with simple or intermediate repair.

CPT Code 11450 applies specifically to the axillary (underarm) region. It covers the surgical removal of affected skin and subcutaneous tissue in a patient with hidradenitis suppurativa, followed by either simple or intermediate wound closure.

The “simple or intermediate repair” component is built into the code. You don’t report a separate repair code alongside 11450 for closing the same wound.

• Code family: Excision-Benign Lesions/Skin Procedures (CPT 10000-19999)
• Body site: Axillary region only (for inguinal site, see CPT 11462)
• Repair type included: Simple or intermediate repair (closure is bundled)
• Excludes complex repair: If complex repair is required, report CPT 11451 instead of 11450
• Specialty users: Dermatologists, general surgeons, plastic surgeons

The code is maintained by the American Medical Association (AMA), which publishes annual CPT updates. As of 2026, CPT Code 11450 remains an active, billable code with no reported revisions. Practices using dermatology EMR software can map this code directly within their procedure libraries to reduce manual lookup errors at the point of care.

When is CPT 11450 used? Clinical indications

CPT 11450 is indicated when a patient with hidradenitis suppurativa (HS) has failed conservative management and requires surgical excision of affected tissue in the axillary area. HS is a chronic inflammatory skin condition characterized by recurrent abscesses, nodules, and sinus tracts.

Surgical candidacy typically involves Hurley Stage II or III disease, where medical therapy (antibiotics, biologics, hormonal agents) no longer controls symptoms. The procedure requires excision of all visibly involved skin and subcutaneous tissue, confirmed by operative report.

• Recurrent abscesses in the axilla unresponsive to antibiotics or biologic therapy
• Hurley Stage II or III hidradenitis suppurativa with axillary involvement
• Persistent sinus tracts requiring wide local excision
• Failed incision and drainage procedures for the same region

This code does not apply to simple incision and drainage (I&D) of individual abscesses, which maps to a different code family. Practices treating HS patients across a broader skin surgery program often also excise other lesions in the same session, such as those reported under CPT 11603.

CPT 11450 reimbursement and fee schedule

Medicare reimbursement for CPT Code 11450 is calculated using the Resource-Based Relative Value Scale (RBRVS) methodology. The national average rate changes annually, so verify precise locality-adjusted figures directly via the CMS fee schedule tool. Place of service also matters: non-facility rates (office-based) are generally higher than facility rates (hospital or ASC).

Key point: Always identify the correct place of service (POS) code on the claim. POS 11 (office) vs POS 22 (hospital outpatient) affects the payment rate applied. Incorrect POS coding is a common source of underpayment for CPT Code 11450.

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Relative value units (RVUs) for CPT 11450

RVUs are the foundation of Medicare payment under RBRVS. Each CPT code carries three RVU components, multiplied by the Conversion Factor (CF) and adjusted by the Geographic Practice Cost Index (GPCI) for the practice’s locality. For 2026 RVU figures, use the FastRVU lookup tool, which pulls current CMS data by code and location.

RVU values for CPT Code 11450 are updated annually by CMS. Label all RVU figures you cite with the applicable year to avoid using outdated reimbursement estimates in internal benchmarking or contract negotiations.

ICD-10-CM codes for CPT 11450

Every claim for CPT Code 11450 requires a supporting ICD-10-CM diagnosis code that establishes medical necessity. The primary code is L73.2, though additional codes may apply depending on the clinical presentation documented in the operative report.

Accurate diagnosis code pairing is essential for claim acceptance and is one of the fundamentals of medical billing overall. A mismatched or unsupported diagnosis code is one of the most avoidable denial triggers.

Refer to AAPC’s CPT-to-ICD-10-CM crosswalk for a complete list of acceptable diagnosis code pairings. Do not use ICD-10-CM codes beyond L73.2 and directly linked hidradenitis codes without confirming their applicability against current CMS guidance.

Modifiers for CPT Code 11450

Modifier selection directly affects how payers process CPT Code 11450 claims. Using the wrong modifier, or omitting one when required, leads to denials that take time and resources to overturn. The three most commonly applicable modifiers are listed below.

Modifier applicability for CPT Code 11450 should always be confirmed against current NCCI (National Correct Coding Initiative) edits, which specify which procedure code combinations are subject to bundling rules. Verify modifier 50 instructions with each individual payer, as some require two line items while others accept a single line with modifier 50 appended.

Documentation requirements for CPT 11450

Inadequate documentation is the most common cause of medical necessity denials for CPT Code 11450 claims. The operative note must support every element of the code descriptor: the anatomical site (axillary), the extent of excision (skin and subcutaneous tissue), and the type of repair performed.

Accurate diagnosis coding for every claim begins with documentation that is specific and complete at the encounter level, which is also the foundation of clean revenue cycle management.

• Diagnosis justification: Confirmed hidradenitis suppurativa diagnosis with documented treatment history and failure of conservative management
• Anatomical site: Explicit statement that the procedure was performed in the axillary region (left, right, or bilateral)
• Extent of excision: Description of the tissue removed, including depth (skin and subcutaneous tissue)
• Repair type: Specific documentation of simple or intermediate closure. Complex repair is reported with CPT 11451 instead of 11450
• Operative report: Complete operative note including anesthesia type, instruments used, intraoperative findings, and wound dimensions
• Pre-operative assessment: Evidence that medical necessity criteria were met prior to surgical intervention

Maintaining HIPAA-compliant documentation practices is non-negotiable for surgical practices. Digital documentation through structured templates reduces the risk of missing required elements at the time of billing.

Practices using digital intake forms can build pre-operative assessment workflows directly into the patient record, so missing information is caught before the surgical date rather than at the time of billing.

Common billing errors and tips for CPT 11450

Claim denials for CPT Code 11450 tend to cluster around a handful of predictable errors. Catching them before submission is far less expensive than chasing down appeals after the fact.

• Wrong repair code billed separately: Simple and intermediate repair is bundled into 11450. Billing a separate repair code for the same wound creates a bundling conflict and triggers denial.
• Incorrect place of service: Using POS 11 (office) when the procedure was performed in a hospital outpatient department (POS 22) results in rate mismatches and potential overpayment recoupment.
• Unsupported modifier 50: Bilateral billing without bilateral documentation in the operative report is a top audit trigger. Ensure the note specifies both axillae.
• Missing medical necessity documentation: Submitting the claim without evidence of prior conservative treatment failure can result in a medical necessity denial even when the procedure itself is appropriate.
• Upcoding to a complex repair code: If the closure was genuinely simple or intermediate, billing CPT 11451 instead constitutes upcoding and creates compliance exposure.

Related CPT codes to know

CPT Code 11450 is part of a family of hidradenitis excision codes differentiated by anatomical site and wound closure complexity. Selecting the wrong code from this group is a common error, particularly when treating patients with HS at multiple sites.

Practices billing CPT 11450 often also need CPT 11102 for a pre-excision skin biopsy, or CPT 11901 when a steroid injection follows the procedure.

Plastic surgery and reconstructive practices treating hidradenitis suppurativa alongside other reconstructive procedures can also explore plastic surgery EMR solutions that support multi-specialty surgical coding environments.

How practice management software supports CPT 11450 billing

Most CPT Code 11450 denials are preventable. Missing documentation, modifier errors, and place-of-service mismatches are the most common causes, and a well-configured billing workflow catches them before the claim reaches the payer. This is where practice management software, specifically claims management software, makes a measurable difference for dermatology and surgical practices.

• Unified claim status: Track every claim as pending, submitted, processing, paid, or in error from one dashboard, instead of checking separate systems
• Pre-submission validation: Background checks confirm that required details, such as insurer membership and authorization information, are in place before a claim can be sent
• Patient record integration: Insurer and policy details attach directly to the patient record, so invoices and claims route correctly without re-entering information
• Payment reconciliation: Match payments back to the original claim and invoice from the same dashboard, rather than reconciling in a separate spreadsheet

Dermatology and surgical practices using Pabau can keep the operative note, the diagnosis, and the claim for a CPT Code 11450 encounter inside one patient record. Structured digital records and claim tracking help catch missing information before it turns into a denial.

Conclusion

CPT Code 11450 is a specific, site-defined surgical code. Its clean-claim rate depends on getting four things right every time: the ICD-10-CM code (L73.2), the place of service, the modifier selection, and the operative documentation. Each element is verifiable before the claim leaves the practice.

Pabau’s claims management software gives dermatology and surgical practices one system to submit claims, track their status, and reconcile payments, cutting down the manual work behind CPT Code 11450 billing. To see how it fits into your billing workflow, book a demo.

Continue your research

Also excising a nail or nail matrix? CPT 11750 covers that procedure, a common companion to axillary excisions in a broader skin surgery program.

Billing a nail avulsion alongside another procedure? CPT 11732 is the add-on code for that scenario.

Following up with a steroid injection after excision? CPT 11901 covers intralesional injection billing.

Frequently Asked Questions