Part B Insider (Multispecialty) Coding Alert

Rely on codes from the 700.x series to keep your claims steady

Corns and calluses are known by several names in podiatry, and if you’re not up to speed on the interchangeable terms, you could cost your practice big bucks.

You may recognize the word “clavus,” since the ICD-9 corn/callus code (700) names it upfront. But here are a few more related words that many podiatrists use interchangeably in their notes:

• Clavi (the word for more than one “clavus”)
• Keratosis
• Keratoma
• Hyperkeratosis
• Intractable plantar keratosis (may be abbreviated as “IPK”)
• Heloma
• Callosity
• Tyloma
• Tylosis
• Durum (this term refers to “heloma durum,” which is considered a “hard corn”).

Watch out: “Tyloma” could lead you down the wrong coding path if you’re not careful. The ICD-9 index in the front of the coding book leads you to several options, such as 757.39 (Other specified amomalies of skin; includes accessory skin tags, congenital; congenital scar; epidermolysis bullosa; keratoderma [congenital]), and this is the wrong path for a basic corn or callus, says Linda S. Templeton, CPC, coding consultant for The Rybar Group Inc. in Fenton, MI. Your best bet when you encounter this term in the documentation is to ask the podiatrist to clarify the condition.

Definitions: If you’re still unsure about your podiatrist’s everyday description of these common conditions, getting familiar with the definitions of “corn” and “callus” 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,” says Sherry Wilkerson, RHIT, CCS, CCS-P, manager of coding and compliance for CHAN Healthcare Auditors in St. Louis. “Between the toes, pressure can form a soft corn of macerated skin, which often yellows,” she says.

• 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: You’re struggling with how to code a patient diagnosis that describes a “keratosis” of the bottom of the great toe and 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: 701.1 (Keratoderma, acquired; Keratosis [blennorrhagica]).

You ask the physician 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 700.