Modifier 59 continues to be the most widely used and incorrectly used modifier. In an effort to minimize the confusion on the correct use of modifier 59, Centers for Medicare & Medicaid Services (CMS) has created four new, more descriptive, modifiers known as the “X” modifiers.Modifier 59 continues to be the most widely used and incorrectly used modifier. In an effort to minimize the confusion on the correct use of modifier 59, Centers for Medicare & Medicaid Services (CMS) has created four new, more descriptive, modifiers known as the "X" modifiers. These new "X" modifiers will go into effect on January 1, 2015. CMS will continue to recognize modifier 59, but notes that the CPT instruction states modifier 59 should not be used if a more descriptive modifier is available.

The following is a description of each of the X modifier:

XE - Separate Encounter, A Service That Is Distinct Because It Occurred During A Separate Encounter

XS - Separate Structure, A Service That Is Distinct Because It Was Performed On A Separate Organ/Structure

XP - Separate Practitioner, A Service That Is Distinct Because It Was Performed By A Different Practitioner

XU - Unusual Non-Overlapping Service, The Use Of A Service That Is Distinct Because It Does Not Overlap Usual Components Of The Main Service

PacificSource will be following CMS guidance for the use of these modifiers for Commercial and both Government lines of business (Medicare and Medicaid).

For more detailed information regarding these modifiers please see the Medicare Learning Network (MLN) Matters at http://www.cms.gov/Outreach-and-Education/Medicare-Learning-Network-MLN/MLNMattersArticles/Downloads/MM8863.pdf

If you have any questions about this notification, please contact your PacificSource Provider Service Representative.