Hammertoe corrections and bunionectomies are two of the 20 most frequently performed outpatient surgery procedures, according to Medicare data. If physicians at your facility are performing these procedures, you should know the answers to three of the most frequently asked foot surgery coding questions.

Don't ?modify' all McBride claims
Question: I often perform modified McBride procedures when my patients require bunionectomies. I submit the claims to my insurer with 28292-22 because code 28292 describes a McBride procedure and I perform the modified McBride. More often than not, the insurer doesn't recognize the modifier -22 for unusual procedural services and only reimburses me for the standard bunionectomy. What type of documentation should I be sending with my claim to justify use of modifier -22?

Answer: Although you may be performing a "modified" McBride, you're still performing a standard bunionectomy, and most insurers won't pay you additional fees for the modified nature of the surgery.

Most insurers will reimburse you the standard fee for 28292 when you document a modified McBride surgery. Some insurers, however, will pay you even less for this service.

For example, Aetna's clinical policy bulletin for bunionectomy includes the modified McBride procedure in its list of "simple" bunionectomies, alongside the Silver type procedure. Aetna advises code 28290 (Correction, hallux valgus [bunion], with or without sesamoidectomy; simple exostectomy [e.g., Silver type procedure]) for this service. Insurers reimburse less for this code than for 28292.

Other insurers will let you report 28292 (Keller-, McBride- or Mayo-type procedure) for a modified McBride. For example, ChampVA lets physicians report modified bunionectomies with this code.

The bottom line is that most payers won't reimburse higher rates when the McBride procedure is "modified," despite the additional effort that some physicians feel that this surgery requires. In fact, some insurance companies pay less when the McBride procedure is modified.

Remember toe modifiers when applicable
Question: I performed a Lapidus bunionectomy on the right foot along with hammertoe corrections on the third and fourth right toes. Medicare reimbursed the bunionectomy but denied the hammertoe corrections as bundled into the bunionectomy. Five weeks later, I performed the same procedures on this patient's left foot. Now all of the procedures for the second date of service have been denied as included in the global allowance for the right foot bunionectomy. How can I code these procedures to appeal the denials?

Answer: You need to code these procedures with special attention to your modifiers so that it is clear to the payor that the procedures were performed on different toes or different feet. For the first bunionectomy, use 28297 (Correction, hallux valgus [bunion], with or without sesamoidectomy; Lapidus-type procedure) followed by 28285 (Correction, hammertoe [e.g., interphalangeal fusion, partial or total phalangectomy]).

Next, append toe modifiers to your hammertoe correction code: T7 (Right foot, third digit) and T8 (Right foot, fourth digit). Finally, you can add modifier -59 (Distinct procedural service) following the toe modifiers to indicate separate sites for the hammertoe corrections.

For the second bunionectomy, mirroring the same procedures on the left foot, follow the steps above, swapping out your hammertoe correction toe modifiers for T2 (Left foot, third digit) and T3 (Left foot, fourth digit). You should also append modifier LT (Left side) to the bunionectomy code to indicate a separate site from the earlier procedure. In addition, append modifier -79 (Unrelated procedure or service by the same physician during the postoperative period) to show your carrier that this bunionectomy is distinct from the global period of the earlier procedure.

Forgetting modifier -79 for any surgery that falls within the global period of another procedure will almost always result in a denial.

Keep in mind that some insurers eschew toe and foot modifiers, preferring only modifier -59. For example, Regence Blue Cross/Blue Shield of Oregon published a directive indicating that claims for 28285 with bunionectomy codes will only be payable if modifier -59 is appended to the hammertoe correction code.

Not all bunions are created equal
Question: My coder suggested that I miscoded my patient's bunion by reporting 735.0 for this diagnosis. I believe this is the appropriate diagnosis code for this condition. Is this accurate?

Answer: The answer depends on the specifics of your patient's bunion, but not all bunions should be coded with 735.0 (Hallux valgus [acquired]). Although CPT lists bunion procedure codes such as 28290 as correction of "hallux valgus (bunion)," a hallux valgus and a bunion are not synonymous, according to ICD-9-CM terminology. If you look up "hallux valgus" in the ICD-9-CM manual, you are directed to code 735.0, but if you look up "bunion," you're referred to 727.1 (Bunion). Dorland's Medical Dictionary defines hallux valgus as an "angulation of the great toes away from the midline of the body or toward the other toes; the great toe may ride under or over the other toes." Dorland's defines a bunion as "abnormal prominence of the inner aspect of the first metatarsal head, accompanied by bursal formation and resulting in a lateral or valgus displacement of the great toe." Carefully document whether your patient's displacement caused the great toe to ride away from the midline or toward the other toes to let your coder choose the most accurate code. If the clinician believes the patient had a hallux valgus but only documented "bunion" and didn't note the great toe's placement relative to the other toes, your coder is left reporting 727.1.

References
- "Medicare: Payment for Ambulatory Surgical Centers Should Be Based on the Hospital Outpatient Payment System," Nov. 30, 2006, available at writeOutLink("www.gao.gov/htext/d0786.html",1).
- Aetna's Clinical Policy Bulletin, Bunionectomy, available at writeOutLink("www.aetna.com/cpb/medical/data/600_699/0629.html",1).
- ChampVA Policy Manual, available at writeOutLink("www.va.gov/hac/forbeneficiaries/champva/policymanual/cvapmchap2/1c2s19-1.pdf",1).