Wiki Modifier 51

[claire@alohavein.com]

Hi everyone, I have a question. We have a patient who underwent LEV (93970) and LEA (93925) procedures on the same day. In addition to the E/M codes with modifier 25, should I use modifier 51 to indicate that one of the procedures is secondary to the primary one? Also, is modifier 51 applicable for in-house tests such as UA (81003), A1c (81003), and EKG (93000) that were performed on the same date of service (DOS)?

 

[csperoni]

Modifier -51. Basically, this modifier tells the carrier - "pay me 50% less for this because another procedure was primary". Carriers will add this on when processing the claim. I don't advise using this modifier at all when coding. In fact, CMS had issued guidance several years ago specifically stating NOT to use -51 and their system will auto append.

https://www.palmettogba.com/palmetto/jmb.nsf/DIDC/8EELF88547~Claims~Modifier%20Lookup

https://www.novitas-solutions.com/webcenter/portal/MedicareJH/pagebyid?contentId=00144532&_adf.ctrl-state=86hvagjfk_33
The main reason being if you add -51 to an incorrect procedure, you will wind up with an underpayment. With Medicare, it's rather straightforward to determine which procedure will pay more, but with commercial carriers, not all payment contracts are based on RVUs so you might bill:
CPT12 $2000. Carrier's allowed amount $600
CPT34-51 $1500. Carrier's allowed amount $800
If you billed with no modifier, carrier would pay $800 plus 50% of $600. $800 + $300 = $1100
If you billed as above, carrier would pay $600 plus 50% of $800. $600 + $400 = $1000

I never recommend using -51.