Correct Use of Surgical Modifier 59, Distinct Procedural Service

There has been a growing concern about the appropriate use of modifiers. However, choosing the correct modifier may depend on whether or not services are considered bundled. Bundling is defined as the inclusion of lesser procedures in the payment for a more comprehensive procedure performed during the same encounter. Typically, only the more comprehensive procedure is reported.

Current Procedural Terminology (CPT) states that sometimes a physician may need to indicate that a procedure or service is distinct or independent from other service(s) performed during the same encounter. In this case, the additional procedure is reported with modifier 59. This modifier distinguishes procedures that are not normally reported together, but are appropriately reported under these specific circumstances. This may represent a different session or patient encounter, different procedure or surgery, different site or organ system, separate incision/excision, separate lesion, or separate injury (or area of injury in extensive injuries) not ordinarily encountered or performed on the same day by the same physician.

Modifier 59 is often associated with the Centers for Medicare and Medicaid (CMS) National Correct Coding Initiative (NCCI) bundling edits as a modifier that may be used to bypass the edits, if appropriate. Modifier 59 is frequently reported incorrectly. The CMS developed the National Correct Coding Initiative (NCCI) to “promote national correct coding methodologies and to control improper coding leading to inappropriate payment in Part B claims. The CMS developed its coding policies based on coding conventions defined in the American Medical Association's CPT Manual, national and local policies and edits, coding guidelines developed by national societies, analysis of standard medical and surgical practices, and a review of current coding practices.” Although these bundling edits were defined for Medicare beneficiaries, many commercial payers follow these bundling guidelines.

NCCI bundling edits define when two procedure (HCPCS/CPT) codes may not be reported together except under special circumstances. If an edit allows use of NCCI associated modifiers, the two procedure codes may be reported together. Documentation in the medical record must satisfy the criteria required by any NCCI associated modifier used. One of the common misuses of modifier 59 is related to the portion of the definition allowing its use to describe “different procedure or surgery”. An example of this is reporting, code 76831 (Saline infusion sonohysterography (SIS), including color flow Doppler, when performed) in addition to code 76830 (Ultrasound, transvaginal).  Code 76831 was valued to include code 76830. Under normal circumstances reporting both codes during the same patient encounter is not appropriate.

The provider should not use modifier 59 solely to report two codes for different types of procedures/surgeries. In general, two procedures/surgeries cannot be reported together if performed at the same anatomic site and during the same patient encounter.  However, modifier 59 would be used when reporting services performed at separate anatomic sites or at separate patient encounters on the same date of service.

CPT indicates bundling of procedures either by using the term separate procedure in the code description or adding notes after some codes.  This separate procedure designation by definition indicates that the procedure is usually a component of a more complex service and is not identified separately. When performed alone, no modifier is needed. If performed with other unrelated procedures/services it may be reported with modifier 59 appended.  A distinct ICD-9 diagnosis code should be linked to the procedure reported.

Example of correct use of 59 Modifier:  A patient was seen by her primary care physician for a well woman exam. Her Pap smear findings indicated low grade squamous intra-epithelial lesion (LGSIL) and a vaginal polyp was also noted at the time of her pelvic exam. The patient returns to see her OB/GYN and following an appropriate history and physical a colposcopic cervical biopsy and endocervical curettage was performed in addition to a biopsy of the vaginal polyp.

The service is reported using CPT 57454 Colposcopy of the cervix including upper/adjacent vagina; with biopsy(s) of the cervix and endocervical curettage and 57100 Biopsy of vaginal mucosa; simple (separate procedure). Modifier 59 was added (i.e., 57100-59) to the biopsy of the vaginal polyp procedure code.


Donna Tyler
Manager, Coding Education

Keisha Sutton
Coding Specialist