Eli's Rehab Report

Up Your Unna Boot Coding Expertise -- Here's How

Find out why you should never report 29700 for removal

Thinking that you only have to use 29580 for Unna boot applications means you could be missing out on the rest of the story. You might also be able to claim associated procedures or be surprised to find that some services you thought were separate are actually bundled into the application itself.

Begin With the Diagnosis

As with any claim, you should support your Unna boot service (29580, Strapping; Unna boot) with a documented and applicable diagnosis, says Suzan Hvizdash, BSJ, CPC, physician education specialist for the department of surgery at UPMC Presbyterian-Shadyside in Pittsburgh.
 
Most payers will cover Unna boot application for very few diagnoses, such as lower-extremity ulcers (707.10-707.19) or strains of the ankle and foot (845.00-845.19). According to a local coverage determination (LCD) from National Heritage, a Medicare carrier for California, "Unna boot application is appropriate in the treatment of ulcerations with and without inflammation due to stasis dermatitis produced by vascular insufficiency. The Unna boot is also appropriate for treating ligamentous injuries (sprains and strains) of the ankle."

Best advice: Covered diagnoses for Unna boot applications vary greatly from insurer to insurer, so you'll have to look to your individual payers for guidance.

Payers often update their policies on the different diagnoses, so check with them from time to time for any additional updates or other information, Hvizdash says.

Unsure? Get a Waiver

If the therapist provides an Unna boot for indications or diagnoses that the payer does not approve (for instance, the therapist may use an Unna boot as a leg-wound dressing in some cases), you should ask the patient to sign a waiver (for Medicare, an advance beneficiary notice, or ABN).

You should ask for the waiver before providing the service. The waiver will make the patient aware that he -- rather than the insurer -- will be responsible for the cost of the service.

Don't Skip Debridements

If the PT provides debridement prior to applying the Unna boot, you should report the debridement codes in addition to the Unna boot application codes:

CPT 97597 -- Removal of devitalized tissue from wound(s), selective debridement, without anesthesia (e.g., high-pressure waterjet with/without suction, sharp selective debridement with scissors, scalpel and forceps), with or without topical application(s), wound assessment, and instruction(s) for ongoing care, may include use of a whirlpool, per session; total wound(s) surface area less than or equal to 20 square centimeters

• 97598 -- ... total wound(s) surface area greater than 20 square centimeters, as appropriate to the size of the wound.

Turn to 2 Units for Bilateral Boots

When medical necessity warrants, the PT may apply an Unna boot to each leg, says Gary W. Barone, MD, associate professor of surgery at the University of Arkansas for Medical Sciences in Little Rock.

In such cases, you can report each application. According to the HealthNow LCD for upstate New York, "when billing the Unna boot for both legs, use modifier 50 (Bilateral procedure) to indicate that this service is bilateral, and list 1 as number of service (modifiers RT and LT are not necessary in this situation)." This will indicate that your PT applied the Unna boots to both legs.

Status Indicators Are Crucial

Code 29580 carries a bilateral status indicator of "1," which means the 150 percent payment adjustment for bilateral procedures applies, according to the Medicare 2006 Physician Fee Schedule. What this means: If you report 29580 with a bilateral modifier or report 29580 twice on the same day by any other means (e.g., with modifiers RT and LT or with a "2" in the units field), Medicare carriers will process the bilateral application of Unna boots at 150 percent of the allowed amount for 1 unit of 29580.
 
Medicare will pay 80 percent of the allowed amount per Unna boot, and then the patient's secondary insurer (or in the absence of secondary insurance, the patient himself) will pay the remaining 20 percent.

Payer tip: Some payers request that you append modifier LT (Left side) or RT (Right side) to indicate which leg the therapist treats when he applies the Unna boot to only one leg. Check with your individual insurer for its guidelines.

Include Supplies, Removal With Service

You should not bill separately for supplies when you report 29580. Medicare and other payers will pay separately for casting and splinting supplies, but Unna boots do not fall into this category.

Instead, payers include the cost of all Unna boot supplies (bandages, straps and paste) in their payment for 29580, Hvizdash says.

Caution: Also, you cannot report a separate service for removing the Unna boot. Coders sometimes mistakenly report 29700 (Removal or bivalving; gauntlet, boot or body cast) for this service, but this is incorrect.

Noridian Medicare, for instance, specifically instructs, "Removal of Unna boot is not a separately reimbursable service. Code 29700 is not appropriate to report this service."