billing destruction of nerves code by podiatrist

I have a physician that has billed 64640/RT x3 and United Healthcare does not want to pay it. i need to explain why we cannot use 3 units on this claim. Can you help

Oct 11th, 2012 - nmaguire 2,606

re: billing destruction of nerves code by podiatrist

AMA - CPT® Assistant
https://catalog.ama-assn.org/MEDIA/ProductCatalog/m2010185/CPTAssistantDecember2009.pdf
pages 11 and 12.
Having said that, each payer determines reimbursement rules.