Explaining Modifier 51, Modifier 59, X Modifiers

Gain insights on modifiers 51, 59, and X modifiers. Definitions, how-to- and guidelines from CMS, AMA, and PCG Software's Virtual AuthTech and iVECoder, and other reputable online coding websites. All data retrieved is relevant as of December 5, 2022.

What is Modifier 51?

Modifier 51 Definition

Modifier Procedures: When multiple procedures, other than E/M services, Physical Medicine and Rehabilitation services, or provision of supplies (eg, vaccines), are performed at the same session by the same individual, the primary procedure or service may be reported as listed. The additional procedure(s) or service(s) may be identified by appending modifier 51 to the additional procedure or service code(s). Note: This modifier should not be appended to designated "add-on" codes (see Appendix D).

Modifier 51 Appropriate Usage

• When both diagnostic procedures have an indicator of "4" in the Medicare Physician Fee Schedule Database (MPFSDB) "Mult Surg" column and both diagnostic procedures have the same "Diagnostic Imaging Family Indicator" in the MPFSDB
• When the same physician performs more than one surgical service in the same session.
• When the MPFSDB indicates a "01-11" in the "Diagnostic Imaging Family Indicator" column.
• When both surgical procedure codes have an indicator of "2" in the MPFSDB "Mult Surg" column.
• Append modifier 51 to the surgical procedure code with the lower physician fee schedule amount.
• Append modifier 51 to the diagnostic imaging procedure with the lower technical component fee schedule amount.
  

Modifier 51 Inappropriate Usage

• Do not use designated add-on codes.
• Do not report on all lines of service.
  

Modifier 51 Notes

• Medicare pays for multiple surgeries by ranking from the highest physician fee schedule amount to the lowest physician fee schedule amount.
• 100% of the highest physician fee schedule amount
• 50% of the physician fee schedule amount for each of the other codes
• Medicare will forward the claim information showing Modifier 51 to the secondary insurance.
• Multiple surgery pricing logic also applies to assistants at surgery services.
• Multiple surgery pricing logic applies to bilateral services (modifier 50) performed on the same day with other procedures.
• Multiple surgeries performed on the same day, during the same surgical session.
• Diagnostic Imaging Services are Subject to the Multiple Procedure Payment Reduction that is provided on the same day, during the same session by the same provider.
  

Modifier 51 Example: Multiple Fractures

The surgeon performs close treatment of humeral shaft fracture; without manipulation (24500). This is a fracture of the humerus (Upper Arm) and Elbow and falls under the musculoskeletal system. You’ve probably billed this hundred if not thousands of times, right? But what happens if you find during surgery that the patient has a clavicle fracture too? What do you fill for? You would bill 24500 regularly, then apply multiple procedures reduction code (modifier 51) to 23500 as 23500-51. 

Sources: PCG’s iVECoder software, PCG’s Virtual AuthTech, and outside source  link

Modifier 59 Background

On January 1, 2015, the Centers for Medicare & Medicaid Service (CMS) introduced 4 Healthcare Common Procedure Coding System modifiers, known collectively as the – X(EPSU) modifiers, as a subset of Current Procedural Terminology (CPT) modifier 59 (distinct procedural service).

Modifier 59 is the most commonly used and abused modifier for Medicare reimbursement of CPT codes in acupuncture, breast biopsies, physical therapy, radiology, surgery, and other medical practices. It often causes incorrect payments, triggering audits, fraud, waste, and abuse (FWA) cases, and escalating costs for everyone.

The 2013 Comprehensive Error Rate Testing reports $2.4 billion was paid on claims containing modifier 59 with a projected error rate of $450 million. While modifier 59 is not the sole culprit, if it caused 10% of the errors it would represent $45 million in damages.

Modifiers XE (separate encounter), XP (separate practitioner), XS (separate structure), and XU (unusual non-overlapping service) are to be used, together with National Correct Coding Initiative (NCCI) edits, to identify distinct services in the same encounter warranting separate reimbursement.

While it encourages migration to the new modifiers, CMS currently allows providers to submit either modifier 59 or the appropriate X modifier to override Correct Coding Initiative (CCI) edits and get paid. The new codes were designed to be more descriptive, provide more precise coding options, reduce errors, improve claims processing, make payments more accurate, reduce FWA and save money. But, because CMS has not issued clear guidance to use the new modifiers, as promised, the change, instead of improving the situation, has exacerbated it. This has caused denied claims, frustrated workers, and increased costs even more.

Modifier 59 Definition

Distinct Procedural Service: Under certain circumstances, it may be necessary to indicate that a procedure or service was distinct or independent from other non-E/M services performed on the same day. Modifier 59 is used to identify procedures/services, other than E/M services, that are not normally reported together but are appropriate under the circumstances. Documentation must support a different session, 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 individual. However, when another already established modifier is appropriate it should be used rather than modifier 59. Only if no more descriptive modifier is available, and the use of modifier 59 best explains the circumstances, should modifier 59 be used. Note: Modifier 59 should not be appended to an E/M service. To report a separate and distinct E/M service with a non-E/M service performed on the same date, see modifier 25.

Modifier 519Appropriate Usage

• Documentation indicates two separate procedures performed on the same day by the same physician
• Represented by a different session or patient encounter, different procedure or surgery, different site, or separate injury (or area of injury)
• Use Modifier 59 with the secondary, additional, or lesser procedure of combinations listed in National Correct Coding Initiative (NCCI) edits.
• Use Modifier 59 when there is NO other appropriate modifier.
• Use Modifier 59 on the second initial injection procedure code when the IV protocol requires two separate IV sites or when the patient has to come back for a separately identifiable service.
  

Modifier 51 Inappropriate Usage

• Code combination not appearing in the NCCI edits
• Submission of E/M Codes
• Submission of weekly radiation therapy management codes (CPT 77427)
• The NCCI tables list the procedure code pair with a modifier indicator of "0"
• Documentation does not support the separate and distinct status
• Exact same procedure code performed twice on the same day
• Multiple administration of injections of the same drug
• If a valid modifier exists to identify the services
  

Modifier 51 Notes

• NCCI coding edits can be found on the CMS NCCI Coding Edits web page.
• Two physicians in the same group, with the same specialty, performing services for the same patient on the same day, are considered by Medicare to be the same physician.
  

Modifier 59 Example: Skin Biopsy and Laser Surgery

A physician uses a tangential biopsy of skin, CPT 11102 (e.g. shave, scoop, saucerize, current); single lesion of skin growth, first growth. However, the dermatologist also performs destruction (e.g. laser surgery) on premalignant lesions as well (precancer skin growth) What do you bill? 

In this example just consider it one surgery billed under time versus another surgery billed under time. If they are done on different anatomic sites on the same side of the body use modifier 59. If they are different sides of the body you want to use RT and LT modifiers.

Modifier 59 Example: Stress Test with ECG

How do you bill a stress test and ECG on the same day but at different times? Your billing should look like this; CPT Code 93015 cardiovascular stress test, CPT 93040-59; Rhythm ECG. If you conduct them at the same time, you would bill them regularly as 93015, and 93040.

Modifier 59 Example: Finger and Toe Services

New material in the National Correct Coding Initiative (CCI) Policy Manual helps clarify hand and foot procedures billed by physicians and podiatrists. We have received frequent questions about the CCI edits in the skin and integumentary systems. The CCI Column 1 and Column 2 edit bundles 11055 (pairing or cutting of benign hyperkeratotic lesion) with 11720 (debridement of the nail(s) by any method; 1-5 nails). Hyperkeratotic lesions are undue thickening of the outer layer of the skin so that a dense horny layer, such as a corn or callosity results. If 11055 and 11720 are performed on the same toe or finger, the bundling edit applies. But if the procedures are performed. On separately identifiable digits, then an overriding modifier 59, or modifiers X (EPSU) can be used by the provider to report the separate site. Correct diagnosis coding will also assist in demonstrating separate sites.

DOWNLOAD CMS GUIDE

What is Modifier XE

Modifier XE Definition

Separate encounter, a service that is distinct because it occurred during a separate encounter

Modifier XE Appropriate Usage

• Coding pairs are part of the National Correct Coding Initiative (NCCI) procedure to procedure edits
• Documentation indicates the services were provided during separate patient/provider encounter
• Use Modifier XE with the Column 2 procedure code in the NCCI files
• Use Modifier XE only when there is no other modifier to describe the situation
  

Modifier XE Inappropriate Usage

• Code pairs are not part of the NCCI procedure to procedure edits
• If another valid modifier exists to identify the separate services
• Submission of E/M Codes
• Submission of Weekly radiation therapy management codes (CPT 77427)
• The NCCI code files show the modifier application as "0"
• Documentation does not support the services were provided during a separate patient/provider encounter
• The patient did not leave and come back for the secondary service
• Exact same procedure code performed twice on the same day
• Multiple administration of injections of the same drug
• Submitted with modifier 59
  

Modifier 59 Example: Skin Biopsy and Laser Surgery

Another subset of Modifier 59, XE refers to two surgeries performed on the same anatomical part of the body such as rotator cuff repair (29827) and partial synovectomy (29820). If it’s the same shoulder toss out 59 and apply XE to 29820. An easy way to remember XE is X-tra entry.

What is Modifier XP

Modifier XP Definition

Separate practitioner, a service that is distinct because it was performed by a different practitioner.

Modifier XP Appropriate Usage

• Coding pairs are part of the National Correct Coding Initiative (NCCI) procedure to procedure edits
• Documentation indicates the services were provided by different practitioners with the same specialty in the same group practice
• Use Modifier XP with the Column 2 procedure code in the NCCI files
• Use Modifier XP only when there is no other modifier to describe the situation
  

Modifier XP Inappropriate Usage

• Code pairs are not part of the NCCI procedure for procedure edits
• If another valid modifier exists to identify the performance of the -services by different practitioners
• Submission of E/M Codes
• Submission of Weekly radiation therapy management codes (CPT 77427)
• The NCCI code files show the modifier application as "0"
• Documentation does not support the services provided by different practitioners
• Exact same procedure code performed twice on the same day
• Multiple administration of injections of the same drug
• Submitted with Modifier 59
  

Modifier XP Example: Different Physicians, Same Day

Modifier XP is a subset of Modifier 59 and can be used when a separate procedure was performed by a separate provider, preferably within the same specialty and legal organization.  An easy way to remember this is XP could stand for X-tra provider and X-tra procedure.

What is Modifier XS

Modifier XS Definition

A separate structure is a service that is distinct because it was performed on a separate organ/structure.

Modifier XS Appropriate Usage

• Coding pairs are part of the National Correct Coding Initiative (NCCI) procedure to procedure edits
• Documentation indicates the services were provided on different organs/structures
• Use Modifier XS with the Column 2 procedure code in the NCCI files
• Use Modifier XS only when there is no other modifier to describe the situation
  

Modifier XS Inappropriate Usage

• Code pairs are not part of the NCCI procedure to procedure edits
• If another valid modifier exists to identify the separate services
• Submission of E/M Codes
• Submission of Weekly radiation therapy management codes (CPT 77427)
• The NCCI code files show the modifier application as "0"
• Documentation does not support the services were provided on a separate organ/structure
• For example, both procedures were performed on the liver during a single encounter
• Exact same procedure code performed twice on the same day
• Multiple administration of injections of the same drug
• Submitted with Modifier 59
  

Modifier XS Example: Two Surgeries, Sam Day, Different Anatomical Areas

XS is yet again another subset of Modifier 59. Just think of it as two surgeries, two separate sites.  It helps you bypass NCCI edits. One easy example of is two injections, one to the elbow (CPT 20550), and one to the tendon  sheath of the knee (CPT 20550). You would bill that as CPT 20550 and CPT 20550-XS.

What is Modifier XU

Modifier XU Definition

An unusual non-overlapping service is the use of a service that is distinct because it does not overlap the usual components of the main service. An easy way to remember Modifier XU is X-tra unusual.

Modifier XU Appropriate Usage

• Coding pairs are part of the National Correct Coding Initiative (NCCI) procedure to procedure edits
• Documentation indicates the service was not part of the usual components of the main service
• Use Modifier XU with the Column 2 procedure code in the NCCI files
• Use Modifier XU only when there is no other modifier to describe the situation
  

Modifier XU Inappropriate Usage

• Code pairs are not part of the NCCI procedure for procedure edits
• If another valid modifier exists to identify the service that does not overlap the usual components of the main service - the column 1 procedure code
• Submission of E/M Codes
• Submission of Weekly radiation therapy management codes (CPT 77427)
• The NCCI code files show the modifier application as "0"
• Documentation supports the service is a component of the main service
• Exact same procedure code performed twice on the same day
• Multiple administration of injections of the same drug
• Submitted with Modifier 59
  

Modifier XU Example: Tow

Another subset of Modifier 59, XE refers to two surgeries performed on the same anatomical part of the body such as rotator cuff repair (29827) and partial synovectomy (29820). If it’s the same shoulder toss out 59 and apply XE to 29820. An easy way to remember XE is X-tra entry.

Conclusion and Summary

Understanding when to use modifier 59 versus modifier 51 is relatively simple. Modifier 51 is used when an additional surgery performed on the same day is more commonly expected. Both modifiers should not be applied to an E/M service. While modifier 51 impacts the payment amount, modifier 59 will affect if your clinic is to be paid at all or if you as a Health should approve and reimburse at all. A general rule of thumb for modifier 59 is that you should look at another modifier first, never apply modifier 59 as a one size fits all billing solution. 

You should have appropriate AI coding software to help evaluate and take into consideration the RVU (relative value units) of the CPTs in order to bill effectively for modifier 51 and modifier 59. 

If you need help with medical codes, PCG has amazing software solutions for providers, health plans, IPAs, MSOs, and TPAs; iVECoder for Clinics, and Virtual AuthTech for Payers. The definitions, reason codes, and all relevant data we’ve provided in this Blog could be at your fingertips.