Podiatry Coding & Billing Alert

Ensuring medical necessity will assure last mile success in getting your physician paid.

Two main challenges may derail your well prepared corn and callus paring/cutting claims are:

• finding the correct diagnosis codes due to multiple confusing names that may be hard to find -- or may not even be in your coding book; and
• the fact that Medicare considers the treatment part of “routine foot care” and won’t cover them sometimes.

Just follow these simple rules for deciphering all of the corn and callus terminology and finding the right conditions when you can receive fair reimbursement for treatment codes 11055-11057 (Paring or cutting of benign hyperkeratotic lesion [e.g., corn or callus]…).

Rule 1: Corn, Clavus or Callus: Consider Them as One

You may recognize the word “clavus,” since the description in the ICD-10 corn/ callus code (L84, Corns and callosities) lists “Callus” and “Clavus” as part of the diagnosis. But other than these two, podiatrists may often use other terms as clavi, keratosis, hyperkeratosis, callosity, or durum to indicate the same condition and you should reach for L84 as soon as you encounter any of these terms. Corns and calluses are thick layers of skin. They are caused by repeated pressure or friction at the spot where the corn or callus develops.

The podiatrist may note one or many of these symptoms:

• Skin is thick and hardened.
• Skin may be flaky and dry.
• Feet show hardened, thick skin areas that may be rubbed or pressed.
• The affected areas are painful and may bleed.

Rule 2: Get Familiar With the Definitions

If you’re still unsure about your podiatrist’s everyday description of these common conditions, get these definitions of “corn” and “callus” in will help.

• A corn is a small, horny area of the skin caused by local pressure (e.g., a shoe or hosiery) irritating the tissue over a bony prominence.

Corns usually occur on a toe, where they form “hard corns.” “Between the toes, pressure can form a soft corn of macerated skin, which often yellows.

• A callus is localized thickening and enlargement of the horny layer of the skin due to pressure or friction. Generally, calluses as well as corns can cause pain, and soft-tissue inflammation may occur around the base of the lesion.

Knowing these definitions is also helpful if you plan to ask the podiatrist for clarification.

Example: A patient visited your podiatrist for evaluation of growths on the bottom of his left heel. You’re struggling with how to code the diagnosis that describes a “keratosis” of the heel. You’ve learned the synonyms for corns/ calluses and remember that this is another name for a callus, but you notice that another nearby code has the same word in its descriptor: L85.1 (Acquired keratosis [keratoderma] palmaris et plantaris).

You ask the podiatrist for more details about the patient’s condition so you can code it properly, and he describes a basic thickening of the skin because of bad shoes. Referring back to the definitions, now you know that it’s just a callus and you can code it as L84.

If the condition were keratosis blennorrhagica, the podiatrist would have described a scaly rash that is associated with Reiter’s syndrome, and this would tell you to code something other than 700, which is for a mere callus.

But if a diagnosis brings you to the L85.- series (Other epidermal thickening), L90.- (Atrophic disorders of skin), or L91.- (Hypertrophic disorders of skin), pay special attention to the definitions under each code.

The definitions can help you verify whether the doctor is using the corn/callus term as a synonym or for a more specific description of the condition.

Rule 3: Count the Corns to Capture Treatment Code

To remove a hyperkeratosis, a podiatrist may use a scalpel, curette, blade, or a spoon-shaped surgical instrument to reduce the lesion. He may also use local anesthesia.

Choose your corn or callus CPT® code depending on how many hyperkeratotic lesions the podiatrist treated:

• 11055 — Paring or cutting of benign hyperkeratotic lesion (e.g., corn or callus); single lesion
• 11056 — …2 to 4 lesions
• 11057 — ….more than 4 lesions.

Coding scenario: A diabetic patient presents with two calluses on her right foot. She complains of cold feet and pain in her calf. The podiatrist determines that the patient lacks a posterior tibial pulse. The podiatrist pares both lesions.

Solution: Code the appropriate-level office visit (99201- 99215, Office or other outpatient visit for the evaluation and management of a new or established patient … ) appended with modifier 25 (Significant, separately identifiable evaluation and management service by the same physician on the same day of the procedure or other service). The patient meets the systemic disease criteria for diabetes mellitus, as well as one Class B finding (absent posterior tibial pulse) and two Class C findings (claudication and temperature change). So you should report the paring as 11056 with modifier Q9 to indicate the documented class findings.

Also report diagnosis codes L84 and E11.51 (Type 2 diabetes mellitus with diabetic peripheral angiopathy without gangrene). The patient has calluses and diabetes without mention of complication, type or instability.

Pitfall: Don’t double up on the codes just because the podiatrist cuts calluses on both feet — use the code that describes the total number of lesions on both feet. If the podiatrist pared one lesion on the left foot and one on the right, report one instance of 11056, not two instances of 11055.

Rule 4: Keep Track of Supplementary Diagnoses to Show Systemic Conditions

Although Medicare my refuse payment for corn/callus removal as part of “routine care,” you may bill for the service if the physician shows medical necessity for the same due to the patient’s systemic condition that led to the corns/calluses. There are multiple ICD-10 codes that Medicare considers to show medical necessity for routine foot care, including corn and callus treatment. Check your local coverage determination (LCD) for specific codes, which will usually include codes from these series:

• E08.-- — Diabetes mellitus due to underlying condition
• E10.-- -- Type 1 diabetes mellitus
• E11.-- — Type 2 diabetes mellitus
• G60.-- — Hereditary motor and sensory neuropathy
• E08.42 — Diabetes mellitus due to underlying condition with diabetic polyneuropathy
• I70.2- — Atherosclerosis of native arteries of the extremities
• I80.-- — Phlebitis and thrombophlebitis
• N18.-- — Chronic kidney disease (CKD).

Note: These codes are only examples of some covered diagnoses; this is not meant to be a complete list. Check your Medicare carrier’s LCD for specific codes.