What Is the 59 Modifier Used For in Medical Billing?

Medical billing involves assigning codes to healthcare services and procedures for claims processing and reimbursement. Modifiers are alphanumeric codes that provide additional information about a service or procedure without changing its definition. They clarify the circumstances of a service, ensuring accurate billing. The 59 modifier indicates a procedure or service was distinct from others performed on the same day.

Understanding the 59 Modifier

The 59 modifier is defined as “Distinct Procedural Service.” It identifies procedures or services, other than Evaluation and Management (E/M) services, that are not ordinarily reported together but are appropriate under specific circumstances. A “distinct” service is separate or independent from other non-E/M services performed by the same provider on the same patient on the same date. This means the procedure was performed at a different anatomical site, during a separate encounter, or involved a different surgery.

The function of the 59 modifier is to prevent inappropriate bundling of services. Many healthcare payers, including Medicare through its National Correct Coding Initiative (NCCI) edits, combine certain services into a single payment if performed together. When applied correctly, the 59 modifier signals to the payer that the services were separate and distinct and should be reimbursed individually. It ensures providers receive proper compensation for medically necessary, independently performed procedures.

The Centers for Medicare & Medicaid Services (CMS) developed specific “X” modifiers (XE, XS, XP, XU) for greater specificity than the broad 59 modifier. These more specific modifiers should be used whenever possible, with the 59 modifier serving as a “modifier of last resort” when no other modifier accurately describes the situation.

Situations Requiring the 59 Modifier

The 59 modifier is used in specific clinical circumstances demonstrating distinct services. One common scenario involves procedures performed on different anatomical sites. For instance, if a patient receives a biopsy on a lesion on their arm and a separate biopsy on a lesion on their leg during the same encounter, the 59 modifier would be appended to the second biopsy code to indicate distinct sites.

Another situation is when services are performed during different sessions or encounters on the same day. If a diagnostic procedure is completed, and based on its results, a separate therapeutic procedure is performed later the same day, the modifier can be used. This indicates the diagnostic procedure was distinct and led to the subsequent therapeutic intervention.

The modifier also applies when different procedures or surgeries, including separate incisions or excisions, are performed that are not typically reported together. For example, if a surgeon removes an implant from one anatomical site and then hardware from a different, unrelated anatomical site during the same encounter, the 59 modifier would be appropriate for the second removal.

Correct Application and Documentation

Applying the 59 modifier correctly is a process within medical billing. The modifier is appended directly to the Current Procedural Terminology (CPT) code for the procedure or service it modifies. On a paper claim form, such as the CMS-1500, the modifier is placed in the designated modifier field next to the procedure code. For electronic claims, it is submitted in the equivalent electronic field.

The use of the 59 modifier must be supported by clear documentation in the patient’s medical record. This documentation must demonstrate why the services were distinct. It should detail information such as:
Different sessions
Different anatomical sites or organ systems
Separate incisions or excisions
Separate injuries

Without this justification, claims using the 59 modifier are prone to scrutiny, audits, and potential denial by payers.

The medical record should contain sufficient information to support the medical necessity of each distinct service. Documentation validates the separate and distinct nature of the services rendered.