Got FAQs?

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By Lisa Lake-Salmon

Running an O&P practice gets more complicated each year. When you have questions, "Got FAQs?" is ready with the answers to help keep your practice running smoothly and efficiently. This month's column tackles your questions concerning knee-orthosis modifiers and claim denials, as well as advice on methods of submitting claims to insurance companies to ensure receipt.

Q: Medicare is now denying knee orthoses if you do not put a KX modifier on the L-Code. Upon researching the KX modifier, I was told that appropriate use of the KX modifier means we are billing for services that are reasonable and necessary, and that those services require the skills of a therapist. Is this correct? What do you know about the KX modifier? We are orthopedists.

A: According to the new knee-orthosis policy effective July 1, 2008, the KX modifier should be appended to both the base knee-orthosis code and any addition code(s) only if the following criteria are met:

  • All the coverage criteria in the "Indications and Limitations of Coverage and/or Medical Necessity" section of the Knee Orthosis Local Coverage.
  • Determinations (LCD) have been met.
  • Documentation is retained in the supplier's files.

Q: We received our first denial for leaving off the KX modifier on a knee orthosis. We did not realize the policy had changed, and we are told this has been in effect since July 1, 2008. We have 26 other claims that were billed the same way, and we assume we will receive denials on them for the same reason. Do we need to submit all these claims to review in order to get them paid? The claims are for patients in regions C and D.

A: If you left off the KX modifier (specific required documentation on file), and your claim denied for CO-50 (not medically necessary), you may contact the claims re-openings department, and they will add the KX modifier to your claim. They will resubmit your claim, and it should be processed within 14 days. For region C, call 866.813.7878; for region D, call 888.826.5708.

Q: I am a small office and do not have electronic billing. We mailed a claim to Aetna, and they claim they did not receive it, I assume, just to delay payment. How can I stop this in the future?

A: When sending a claim or medical records to an insurance company via U.S. mail, I recommend sending it by certified mail with return receipt requested. This is proof that your claim was received. The insurance company is unable to dispute this since you have a signed receipt from them. If you have Internet access, you can submit your claim free of charge to Aetna Insurance online at

Q: I recently received a denial from United Health Care (UHC) for L-1858 stating the procedure code was invalid. The date of service I am billing for is July 20, 2007. Was L-1858 not a valid code then? When did it change and what is the new code?

A: On the service date for which you billed, L-1858 (knee orthosis, molded plastic, polycentric knee joints, pneumatic knee pads, custom fabricated) was a valid code. Effective January 1, 2008, L-1858 was changed to L-1846. I recommend contacting UHC and requesting that your claim be reprocessed since the L-1858 was a valid code on July 20, 2007. Your claim was denied in error.

Lisa Lake-Salmon is the executive vice president of ACC-Q-Data, which provides billing, collections, and practice management software. She has been serving the O&P profession for more than a decade. We invite readers to write in and ask any questions they may have regarding billing, collections, or related subjects. For more information, contact