The Arizona Wound Care Ring

The Pattern

In the Phoenix metropolitan area, 23 nurse practitioners billed Medicare a combined $514.6M for skin substitute products. They treated just 3.0K patients — an average of $173.0K per patient.

The top biller, Ira Denny of Surprise, Arizona, billed $135.2M for 90 patients — that's $1.5M per patient. To put that in perspective, the median annual income in Surprise, AZ is about $68,000. Denny billed Medicare more per patient than 22 years of the typical resident's salary.

These providers are concentrated in a tight geographic cluster: Surprise, Phoenix, Chandler, Gilbert, Mesa, Tucson, and Goodyear — all within the greater Phoenix metro area. And they share something else: a nearly identical markup ratio of 1.28x.

All 23 Arizona NPs

Every nurse practitioner in Arizona flagged for significant wound care billing in our dataset. Sorted by total billing:

The Math

Skin substitute products (coded as Q4xxx in Medicare) are biological or synthetic materials applied to chronic wounds — diabetic ulcers, venous stasis ulcers, pressure sores. Each application typically bills between $500 and $5,000+ depending on the product and quantity.

At $1.5M per patient, Ira Denny's billing implies that each of her 90 patients received skin substitute applications worth hundreds of thousands of dollars. Even at $5,000 per application, that would require roughly 300 applications per patient.

For context: a typical wound care patient might receive 5-20 skin substitute applications over the course of treatment. Three hundred applications per patient is not clinically normal.

Denny billed for 153.3K total services across just 90 patients — that's 1.7K services per patient.

The Identical Markup

Perhaps the most striking pattern isn't the dollar amounts — it's the consistency. Of the top 7 billers (each over $16M), all seven have a markup ratio of exactly 1.28x.

In a free market, markup ratios vary based on product selection, supplier relationships, and billing practices. When 8+ independent providers all land on the exact same 1.28x markup, it suggests they may be using the same billing protocol, the same supplier, or operating under coordinated guidance.

Arizona vs. the Nation

Arizona is a national outlier in wound care billing. Compare the per-patient cost of wound care across the top states:

Arizona's per-patient wound care cost dwarfs every other state. The national average for wound care states in this dataset shows per-patient costs in the low thousands. Arizona's figure is in the tens of thousands — driven almost entirely by this cluster of 23 nurse practitioners.

What These Codes Are

The billing in this investigation centers on Q4xxx HCPCS codes — Medicare's category for skin substitute products. These include:

• Q4101–Q4281: Various skin substitute grafts and wound care products
• Products like Apligraf, Dermagraft, EpiFix, and dozens of others
• Applied to chronic wounds: diabetic foot ulcers, venous leg ulcers, pressure injuries
• Each application bills anywhere from $500 to $5,000+ per cm²

The HHS Office of Inspector General has called skin substitutes "particularly vulnerable to fraud schemes" due to their high per-unit cost, the difficulty of auditing wound measurements, and the ease of upcoding product quantities.

In June 2025, the Department of Justice announced its largest-ever healthcare fraud enforcement action — a $14.6B takedown involving 324 defendants. Wound care billing, particularly skin substitutes, was at the center of the operation.

Methodology

This analysis uses CMS Medicare Provider Utilization and Payment Data (2023). We identified providers with significant billing for Q4xxx skin substitute codes, aggregated by state and specialty. Markup ratios are calculated as submitted charges divided by Medicare payments. Per-patient costs are calculated as total wound care payments divided by unique beneficiaries.

All data is publicly available from data.cms.gov. Our analysis code and methodology are documented on our methodology page.