What does modifier -59 represent?

Modifier -59 is used to indicate that a procedure or service is distinct or separate from other services performed on the same day. This means that the procedure has its own unique clinical context and is not simply a routine part of a more extensive service. For instance, if a healthcare provider performs multiple procedures that are normally bundled together but there is a legitimate clinical reason for performing them separately on the same day, modifier -59 should be appended to the appropriate CPT code to clarify this distinction.

The use of modifier -59 allows for appropriate billing and reimbursement by communicating to payers that the services were warranted as separate interventions. This can help prevent denials caused by the assumption that the billed services overlap or are redundant in some way.