How will you bill a separately performed service if it falls under the global period of another surgery? This is a common scenario in postoperative care, where the lines between routine recovery and new medical issues often blur.
Fortunately, the answer to this question is simple. You can use modifier 24 to bill the second service. However, the actual application of this modifier is quite complex. That’s why our billing experts at NeuraBill have compiled this detailed guide on how to use the 24 modifier effectively. So, let’s start.
Modifier 24 – Description
Modifier 24 is defined as:
“Unrelated Evaluation and Management Service by the Same Physician or Other Qualified Healthcare Professional During a Postoperative Period.”
To understand how to use this modifier correctly, you first need to understand the concept of the Global Surgical Period. A surgery is not an independent procedure. Often, the surgery is bundled with other services that become necessary before and after the surgery. Each surgical procedure has a specific set of days in which these sub-services are considered bundled. This is called the Global Surgical Period.
When a surgeon performs a procedure, insurance payers (specifically Medicare) pay a single fee that covers the surgery itself, pre-operative visits, and routine postoperative care. Usually, the global period is either 0 days, 10 days, or 90 days, depending on whether the surgery was minor or major.
During this window, most visits to the surgeon are considered “included” in the surgical fee. However, patients often get sick or develop new issues during this time that have nothing to do with the surgery. If you bill a standard office visit during this time without a modifier, the system will assume it is routine post-op care and deny payment. Modifier 24 tells the system: “Stop! This visit is for a completely different reason.”
However, the 24 modifier has its own limitations. You cannot use it for all types of services. According to Medicare guidelines, this modifier should only be used for evaluation and management (E/M) codes (99202-99499) and General Ophthalmological services (92002-92014).
Modifier 24 – Usage Examples
To better understand how modifier 24 works, let’s look at a couple of examples in which it can be used:
New Injury During Major Recovery
Suppose a patient undergoes a total hip replacement surgery (CPT 27130). This procedure has a global period of 90 days. However, 50 days after the surgery, the patient slips while walking and injures his shoulder. The shoulder becomes swollen and inflamed. So, the patient visits the same orthopedic practice from which he had the surgery.
The physician deeply assesses the shoulder and diagnoses a simple muscle injury. Now, since this second visit to the practice is entirely unrelated to the hip surgery, the billing department should bill the office visit (e.g., 99213) with modifier 24. Without it, the payer will assume that a visit to the orthopedist within the 90-day window is a routine check-up for the repaired hip.
Distinct Condition
A patient has a breast biopsy (CPT 19101), a minor procedure with a 10-day global period. Five days later, the pathology results come in, confirming a malignancy. The patient returns to the office immediately to discuss the diagnosis, next steps, and treatment options.
While the visit is related to the disease, the decision-making for major surgery (mastectomy) goes beyond routine recovery from the biopsy. The discussion of the new treatment plan constitutes a significant, unrelated E/M service. So, in this case, the recent visit should be billed with modifier 24, as it occurred within the postoperative period of the biopsy.
Accurate Usage Guidelines for Modifier 24
Knowing the definition isn’t enough. Several rules dictate the proper use of modifier 24. You must be aware of these rules to know exactly when to apply this modifier and when not to. The following are some guidelines to help you make the decision:
Understand When to Use 24
- Unrelated E/M Service: The visit must be for a diagnosis different from the original diagnosis. However, you can still use the 24 modifier for the same diagnosis as that of the original procedure if the problem is at a different anatomical site.
- Same Physician/Specialty: Use it when the billing provider is the same one who performed the original procedure (or a provider from the same specialty in the same group).
- Timing: The service must occur during the postoperative global period, starting a day after the procedure.
- Underlying Health Issues: Use it for treating underlying conditions that are not part of the surgical recovery process.
Understand When NOT to Use 24
- Routine Post-Op Care: Pain management, wound checks, and suture removal are included in the global package.
- Same Day as Procedure: Do not use modifier 24 for services on the day of surgery.
- Different Physician: For example, if a cardiologist sees a patient after an orthopedic surgery, the global period does not apply to the cardiologist. No modifier is needed.
- Surgical Complications (Medicare): Under CMS rules, treating an infection or minor complication in the office is considered part of the global package.
- Irrelevant Codes: Do not use the 24 modifier with surgical procedures, labs, X-rays, or supply codes.
Modifier 24 vs 25: Clarifying the Difference
Many billers confuse modifiers 24 and 25. Reason? They both unbundle E/M services. However, some key differences make them completely distinct. The table below clarifies the differences between the two:
| Feature | Modifier 24 | Modifier 25 |
|---|---|---|
| Definition | Unrelated E/M service by the same physician during a postoperative period. | Significant, separately identifiable E/M service on the same day as a procedure. |
| Timing | Used during the 10-day or 90-day global period (days 1-90). | Used on the same day the procedure is performed (Day 0). |
| Purpose | Separates a visit from postoperative care. | Separates a visit from a procedure performed on the same day. |
| Example | Treating a sprained ankle 30 days after knee surgery. | The same physician renders a cardiology office visit and a cardiovascular stress test. |
Final Thoughts on Modifier 24
This is a lot of information to take in. So, let’s do a quick recap of the main points that we discussed in this guide.
- Modifier 24 is used to identify an unrelated evaluation and management (E/M) service performed by the same physician or group during the global postoperative period.
- It should only be appended to E/M codes (99202-99499) and General Ophthalmological services (92002-92014).
- The treatment of surgical complications of the original procedure cannot be billed with the 24 modifier.
Even after following all the guidelines, denials are likely to occur. However, the chances of denial can be decreased by outsourcing medical billing and coding services to specialized third-party billing companies, like NeuraBill.
FAQs
Can we bill modifiers 24 and 25 together?
In rare circumstances, yes. For instance, if a patient is in the postoperative period of a previous surgery (requiring modifier 24 on the E/M visit to unbundle it from the past surgery) and, during that same visit, a significant, separately identifiable E/M service leads to a new minor procedure being performed that day, then modifier 25 wil be be appended to the E/M service code to unbundle it from the new procedure.
Do you apply modifier 24 or 25 first?
Modifier 24 always goes first (left-most position), followed by modifier 25.
Does modifier 24 require documentation?
Yes, absolutely. You must provide detailed and accurate documentation that shows the evaluation and management service was not related to the original surgical procedure.
What is the difference between modifiers 24 and 59?
Modifier 24 is for an unrelated evaluation and management (E/M) service by the same physician during the postoperative period (global surgery), while modifier 59 is for a distinct procedural service that was separate from other non-E/M services performed on the same day, indicating different anatomical sites, encounters, or purposes.
What is the difference between modifiers 24 and 78?
Modifier 24 is used for an E/M service that was unrelated to the original surgery. Modifier 78 is used for a procedure (return trip to the operating room) that is related to the original surgery.
Does modifier 24 affect reimbursement?
Yes, it directly affects reimbursement. Without modifier 24, any E/M service billed during a global period by the same surgeon will be automatically denied.
What is the CMS guideline for modifier 24?
CMS has issued several guidelines that underscore the accurate and inaccurate usage of modifier 24. Among them are some important billing tips, such as the modifier must always be appended to the E/M service code, the visit must occur in the postoperative period of a surgery, the purpose of the visit must be to evaluate and manage an unrelated issue, and the physician rendering the unrelated E/M service must be the same as the one who performed the original surgery.
