Although the coding itself is straightforward there is only one Unna boot code this does not necessarily mean that reporting this service will be problem-free. An Unna boot is a medicated dressing that surgeons use to treat varicose leg ulcers, which may occur due to increased venous pressure from venous insufficiency or other outflow problems. Unna boots also are used to manage lymphatic edema and sometimes are used for sprains, strains, minor fractures and, sometimes, as a protective bandage for grafts on wound burns.
Application of an Unna boot is reported using 29580 (Strapping; Unna boot), which consists of layering a bandage impregnated with Unna paste (gelatin, glycerin and zinc oxide) on the leg ulcer until the bandage becomes semirigid. The combination of pressure and medication aids the healing process. .
Multiple treatments typically are required, usually once a week and sometimes more frequently, says Elaine Elliott, CPC, a general surgery coding and reimbursement specialist in Jensen Beach, Fla. .
Tip 1: Only significant and separate E/M services should be reported on the same day as Unna boot application. Because Unna boots are applied during a series of visits, E/M services (for example, an established patient visit) should not be reported when the patient comes for scheduled treatment unless the patient has another problem. In such cases, modifier -25 (Significant, separately identifiable evaluation and management service by the same physician on the same day of the procedure or other service) should be appended to the E/M code. .
The appropriate E/M service code may be reported separately for the initial assessment of the condition that led to the decision to apply the Unna boot. .
Note: Most procedures, including Unna boot strapping, incorporate a preprocedure evaluation that involves routine follow-up care. A second diagnosis, although not necessary for Medicare carriers, always is helpful by indicating why the visit was separate and significant. .
Tip 2: Bill for supplies separately only if the carrier in question instructs you to do so in writing..
Although casts, splints and other supplies may be separately payable, Medicare does not include Unna boot dressings in the same category. Therefore, supplies (bandages, straps and paste) should not be reported separately to Medicare carriers, and most private carriers are likely to follow Medicare’s lead. .
Medicare considers the Unna boot a dressing rather than a cast and says it is included in 29580 the application code ” Elliott says. .
Note: The procedure is valued at 1.23 relative value units when performed in a nonfacility setting. .
Tip 3: You can bill for debridements separately..
Some patients (those with venous stasis ulcers [454.0] for instance) may require debridements. In such cases a separate debridement code (typically 11040 Debridement; skin partial thickness; 11041 skin full thickness; 11042 skin and subcutaneous tissue; 11043 skin subcutaneous tissue and muscle; or 11044 skin subcutaneous tissue muscle and bone) may be reported. .
If the Unna boot is applied by a nurse or another nonphysician practitioner (NPP) such as a physician assistant or a nurse practitioner these debridement codes should not be reported even under “incident to ” says Marcella Bucknam CPC a general surgery coding and reimbursement specialist and a coding instructor at Clarkson College in Omaha Neb. .
Instead Bucknam says the NPP’s services should be reported using 97601 (Removal of devitalized tissue from wound[s]; selective debridement without anesthesia [e.g. high pressure waterjet sharp selective debridement with scissors scalpel and tweezers] including topical application[s] wound assessment and instruction[s] for ongoing care per session) or 97602 ( non-selective debridement without anesthesia [e.g. wet-to-moist dressings enzymatic abrasion] including topical application[s] wound assessment and instruction[s] for ongoing care per session). .
Tip 4: Bilateral treatments may be reported. If Unna boots are applied to the left and right leg the procedures should be reported to Medicare carriers by appending modifier -50 (Bilateral procedure) to 29580 says Elliott. Some Medicare carriers may request that modifiers -LT (Left side) and -RT (Right side) be used instead. Others such as Empire Medicare Services the Part B carrier in New Jersey and parts of New York state instruct providers to use -LT or -RT if only one side is performed and to append modifier -50 if the Unna boot is applied bilaterally. .
Many private carriers also may require the procedures to be reported as follows: .
- 29580-50 .
- 29580-RT. .
The bilateral Unna boot application should be reimbursed at 150 percent of the fee schedule rate based on Medicare’s bilateral surgery guidelines Elliott says. .
Tip 5: If the Unna boot is applied at the hospital a lesser amount should be billed. The Medicare fee schedule values 29580 at 1.23 RVUs in an office setting but only 0.98 RVUs if the application is performed in the hospital. A local medical review policy regarding Unna boot from CIGNA the Part B carrier in North Carolina states that “if this procedure is performed in a facility setting a reduced reimbursement will be allowed” (emphasis added). .
Tip 6: Nonphysician practitioners may bill for the service under incident to guidelines. Although any associated debridements are billed using 97601 or 97602 the application of the Unna boot itself may be reported incident to if it is performed by the NPP under the “direct personal supervision” of the physician. Under incident to guidelines direct personal supervision means the surgeon must be in the suite but need not be in the same room as the NPP when the Unna boot is applied. .
Note: If the service is performed in a hospital by nursing staff it should not be reported by the surgeon because it will be reported by the hospital to Medicare Part A. .
Tip 7: Contact carrier before using 29580 for any other strapping or dressing service. Physicians have received conflicting instructions concerning this issue. In July 1999 The CPT Assistant stated that high-compression bandage systems such as PROFORE multilayer compression bandage or Dynaflex three-layer compression bandage should be reported using 29580 with modifier -22 (Unusual procedural services) appended. .
Note: Modifier -22 should be appended only if significant additional work or time was required. Most coding specialists interpret that as at least 25 percent or more. .
Some local medical review policies however state that 29580 “represents the Unna boot service of application only; it is not to be used for billing other strapping or dressing changes.” These carriers may require that 29799 (Unlisted procedure casting or strapping) be reported for high-compression bandage systems. You should contact the carrier for specific requirements. A description of the procedure should be listed in box 19 of the claim form. .
If the Unna boot is used as a postoperative dressing it is not a separately payable service because payment for surgical dressings applied during a patient encounter is included in the fee schedule amount for the service Elliott adds. .
Tip 8: Make sure the ICD-9 code is an approved diagnosis. Unna boot applications are covered for specific conditions only. Although carriers may vary greatly in the number of published diagnoses that support Unna boot application most accept the following indications and diagnoses (often represented by more than one ICD-9 code): .
- varicose veins of lower extremities
- venous insufficiency unspecified
- chronic ulcer of skin
- decubitus ulcer of lower extremity
- ulcer of lower limbs
- edema of lower extremities.
Most carriers explicitly do not cover Unna boot applications for sprains strains or small fractures because other treatments such as elastic bandage or taping are just as effective clinically and cost less. Varicose veins or phlebitis of the lower leg is not covered but postphlebitic syndrome (459.1) and varicose veins of lower extremity with ulcer and inflammation (454.0-454.2) are reimbursable. .
Tip 9: Obtain a waiver from the patient when necessary. If the Unna boot is used for indications or diagnoses that are not approved ask the patient to sign a waiver (for Medicare an advance beneficiary notice or ABN) to indicate that he or she understands that cash payment for treatments (or some other arrangement) is required. .
Tip 10: Do not report the removal of the Unna boot separately.Code 29700 (Removal or bivalving; gauntlet boot or body cast) should not be used to report the removal of an Unna boot. Assuming the surgeon examined the patient and documented the encounter the boot removal can count toward an appropriate-level E/M service. “