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Internal Medicine Coding Alert

Draw Distinction Between Modifiers -51 and -59 to Avoid Denials

- Published on Mon, Oct 01, 2001
CPT language describing modifiers -59 (distinct procedural service) and -51 (multiple procedures) can confuse internists and coders alike when billing for separate procedures. Stephanie Jones, NRCMA, NRAHA, CPC, director of audit programs for eCompliance Doc., says it helps to change the wording to clarify the difference. She suggests adding the word "related" to the definition of modifier -51 to read "multiple (related) procedures." She describes modifier -59 as "distinct, multiple (unrelated) procedures."
"When the doctor is considering appending modifier -51 he or she can say, 'I've done multiple related things today, and, payer, you shouldn't pay me for the full amount of the secondary procedure,'" Jones says. Modifier 51 alerts carriers to reduce payment on the second through fifth procedures by 50 percent or less. Because the patient is already on the table and under anesthesia and the incision is made, the second procedure needs less work.
"When applying modifier -59, the doctor says, 'I did things that required me to do the entire procedure, so, payer, it is appropriate to pay me because I did all the work for both procedures,'" she says.
Definitions Revamped  
Modifier -51 allows an internist to receive payment for his or her services when performing multiple procedures. Because the patient is already prepped for a major procedure, all other procedures done at the same time require appending modifier -51. This informs the payer that although the internist's work did not require a start-to-finish approach, the service still warrants partial reimbursement. The major surgical procedure is reported without the modifier. Modifier -51 is always appended to the lower-valued (lowest relative value unit) code. The rule for modifier -59, on the other hand, is not as black and white, which is part of the reason many coders still have trouble distinguishing the differences between the two modifiers.
In an effort to eliminate some of the coding confusion, CPT revised the descriptor of modifier -51 in 1997. The new definition stated that, unlike modifier -59, modifier -51 could not be appended to designated "add-on" codes, in other words, codes that are bundled. Modifier -59 was designed to unbundle codes when the procedures were distinctly separate.
Modifier -59 is appended solely to surgery procedure codes. It is never used on E/M codes.
In 1999, CPT clarified the differences between modifier -51 and -59 by deleting the words "on the same day" from the definition of modifier -51. 
Using Modifier -51  
Internists should bill the full value for both procedures -- even when appending modifier -51 -- because the carrier will automatically reduce the lesser-valued procedure by 50 percent. There is a chance Medicare will still reduce the code appended with the -51 modifier and the provider will receive only 25 percent for the [...]

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