What is Modifier 59 in Medical Billing?

We often hear people say that medical billing is complex. But have you ever wondered what makes it intricate? Well, for starters, there are thousands of procedural codes, and you must support the rendered service by using a relevant diagnosis code from another large set of codes (ICD-10). Besides, the documentation requirements further add to the complexity.

But the complications do not end with that. There are modifiers, not one but many, that are designed to ensure coding specificity and provide additional details about the performed procedure. This guide is dedicated to discussing one of these codes, modifier 59. 

So, without further ado, let’s get right into the details.

Modifier 59 – Description

It indicates distinct procedures (except E/M services) that are primarily not reported together. However, these services are separately reimbursable under certain circumstances. 

But there’s one key requirement that you should not take for granted. That is, documentation! It must justify the use of modifier 59. Simply put, it must support distinct procedures/surgeries, different sessions, separate lesions, separate excisions/incisions, or separate injuries that the same healthcare practitioner encounters or performs on the same day.

Understand the X-Modifiers

The Centers of Medicare and Medicaid (CMS) introduced the X{EPSU} modifiers in January 2015. Consider these as a subset of modifier 59. They offer higher coding specificity, and with these, CMS aimed to limit the overuse and misuse of 59. Here’s what these modifiers entail:

• XE: It highlights that another distinct service was performed on the same patient in a separate encounter on the same date.
• XP: It indicates that a different healthcare provider rendered the service.
• XS: It identifies that the physician performed the procedure on a separate organ/structure.
• XU: It means that the performed service is distinct as it does not overlap with the initial service.

Modifier 59 – Usage Examples

Let’s take a look at some of the real-world scenarios where 59 applies:

Biopsy and Destruction of Separate Lesions

Picture a dermatologist who identifies a small, clinically suspicious, pigmented lesion on the patient’s shoulder. Thus, he performs a biopsy for diagnosis (CPT code 11104). Following it, the dermatologist destroys a distinct, separate lesion 3 cm away on the same shoulder using cryosurgery for clinical actinic keratosis (CPT code 17000).

Here, you should code the services like this:

• Column 1: 17000
• Column 2: 11104-59

The CCI bundles biopsy code and lesion destruction codes together. Therefore, according to the NCCI Procedure-to-Procedure Lookup tool, you must append modifier 59 with the column 2 code to highlight that it was performed on a separate lesion with a different intent.

Trimming and Debridement of Different Nails

Assume a patient with severe peripheral vascular disease that requires routine foot care. As a result, the podiatrist performs debridement (CPT code 11720) on the patient’s right great toe due to dystrophic nail changes. However, during the same encounter, the provider also performs routine trimming (CPT code 11719) on the patient’s left lesser toes, where they are non-dystrophic.

Coding should be as follows:

• Column 1: 11719
• Column 2: 11720-59

CCI bundles the codes 11719 and 11720. But in this scenario, both services were distinct, i.e., trimming was done on the left lesser toes, and debridement was performed on the right great toe. Thus, modifier 59 is necessary here to ensure payment for both services.

Physical Therapy with Distinct Time Intervals

Imagine a patient who is scheduled for physical therapy services for shoulder pain. The therapist spends 15 minutes performing manual therapy (CPT code 97140) focusing on joint mobilization. He then stops, re-evaluates the patient’s condition, and spends another 15 minutes performing therapeutic activities (CPT code 97530).

Here’s how you should code both services:

• Column 1: 97140
• Column 2: 97530-59

As per the CCI, both codes are mutually exclusive. However, modifier 59 is essential with CPT 97530. It indicates that both manual therapy and therapeutic activities were rendered in distinctly different 15-minute intervals.

When to Use Modifier 59?

You can use this modifier when any of the following is true:

Determine: Where Did the Service Occur?

Use modifier 59 if:

• Anatomical Site: The physician performed the procedure on a completely different location on the body.
• Separate Lesion: You treated two distinct, non-contiguous lesions of the same type. Common for dermatology.
• Separate Incision/Excision: The service required a new, distinct cut or surgical opening from the first procedure.

Identify: When Did the Service Occur? 

Append modifier 59 if: 

• Different Encounter/Session: The patient left the clinic/operating room and came back later the same day for a second, separately planned care service.
• Distinct Time Interval: The two services occurred in entirely different, non-overlapping 15-minute blocks. Common in physical therapy.

Understand: Why Did You Do It?

Report modifier 59 if:

• Different Procedure/Surgery: The two procedures are entirely different in method or intent, even if they are bundled.

Warning: Always try to use the X{EPSU} modifiers first. In case they do not apply to a scenario, only then opt for 59.

When Not to Use Modifier 59?

Understanding when to use a modifier is only one part. Learning when not to append is equally essential to prevent audit risks due to misuse or overuse. Luckily, for your ease, we have listed non-applicable scenarios for modifier 59 below:

• Do not append it with an E/M service code.
• Avoid reporting it when another, more valid modifier exists to describe the situation to the payer.
• If the documentation is insufficient and cannot support the use of modifier 59, avoid appending it.
• Do not report modifier 59 for the administration of multiple injections containing the same medication.
• Avoid using it when the NCCI table lists the procedural code pair with an indicator ‘0’.

Modifier 59​ vs. 25

The table below offers an at-a-glance description of the differences between modifiers 25 and 59:

	Modifier 25	Modifier 59
Description	It indicates significant, separately identifiable E/M services.	It identifies distinct procedural services.
Purpose	It modifies E/M codes (99202–99215).	It separates two bundled procedural (CPT) codes.
Documentation Requirements	Your documentation should explain the thought process that makes the second E/M service significant beyond the standard pre- and post-work for the procedure. E.g., different diagnosis, new patient concern, complexity of decision-making.	Your documentation should focus on the physical act that makes the second procedure distinct. That is, location, time of service, incision site, etc.

Final Thoughts

Modifier 59 is an integral code that can help you uptick your revenue by bypassing bundling edits. When you collect maximum reimbursement that is rightfully yours, your practice thrives, and you can continue providing quality care to the patients.

But, there’s a catch! Overuse or misuse it to get unfair payments, and you will have to deal with the outcomes. These can range from simple claim denials to adverse consequences, such as audit risk, reputational damage, heavy financial penalties, and lawsuits.

Thus, we recommend that you use modifiers with care and avoid going overboard in their usage. Besides, think about partnering with a leading medical billing company like NeuraBill for seamless medical billing and coding services.