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Published 5/1/2015
Mary LeGrand, RN, MA, CCS-P, CPC

“X” Subset Modifiers and Orthopaedic Clinical Examples

Confusion about modifier 59 and the “X” subset modifiers is evident in the responses from orthopaedic practices to a recent survey conducted by Karen Zupko & Associates, Inc. Modifier 59 is used to indicate that a procedure or service was distinct or independent from other non-evaluation and management services performed on the same day. The “X” subset modifiers were introduced in 2013 to define specific subsets of the -59 modifier. Practices are submitting claims to private payers and Medicare carriers without clarifying rules, guidance, and examples of how to use the new modifiers, and receiving mixed responses. Examples include, but are not limited to, the following:

  • Before it provided written instructions, one carrier denied all claims submitted with “X” modifiers.
  • Some claims submitted to private payers with the “X” modifier were paid, even though standard coding rules allowing modifier 51 were applicable.
  • In cases where combinations should not have been reported at all, private payers allowed the payment because the “X” modifier had been appended. This is a concern because incorrect use of the “X” modifiers may result in a risk to the practice.
  • One payer instructed practices to append both modifier 59 and the “X” modifier and paid when this combination was reported. This action directly conflicts with instructions from the Centers for Medicare and Medicaid Services (CMS), which clearly state that the two modifiers should never be reported together.

Results such as these mean practices should keep a sharp eye on payer policies, ensure accurate coding, and analyze Explanations of Benefits.

Because CMS is continuing use of modifier 59, practices should not be submitting an “X” modifier on a primary claim submission. This article addresses possible clinical scenarios in orthopaedics that may require the use of an “X” modifier on appeal, along with additional documentation.

What are the “X” subset modifiers?
CMS introduced “X” subset modifiers for use instead of modifier 59; consequently, the “X” modifier and modifier 59 are not intended to be submitted on the same CPT code. The following examples assume that modifier 59 is not the most specific modifier and an “X” modifier is required.

XE—Separate encounter, a service that is distinct because it occurred during a separate encounter. This modifier should only be used to describe separate encounters by physicians/providers of the same group and the same specialty when the CPT codes reported at the different encounters have a National Correct Coding Initiative procedure-to-procedure (NCCI PTP) edit in place (Column 1/Column 2 edit).

Clinical scenario: The surgeon sees the patient in the morning, diagnoses a closed displaced left radius fracture, and applies a stabilization splint, knowing that the patient will require definitive management when an operative suite is available. Later that day, the surgeon performs open reduction/internal fixation (ORIF).

CPT codes reported for this date of service: 25607—Open treatment of distal radial extra-articular fracture or epiphyseal separation, with internal fixation; 29125-XE—Application of short arm split; static

Rationale: An NCCI PTP edit exists between CPT codes 25607 and 29125 requiring either the modifier 59 or the XE. This example shows the XE whether required for appeal or allowed to be reported on the initial claim as the most specific modifier. Note that a splint applied at the same session as the surgical fracture care is inclusive to the global surgical package, while a temporary splint is separately reportable. The services occurred on the same day by the same surgeon or surgeon or other qualified healthcare provider in the same group. A more specific modifier (RT, LT, Finger, 50, 59, or 76) is not appropriate for this code combination.

XS—Separate structure, a service that is distinct because it was performed on a separate organ/structure. This modifier should only be used to report services performed on the same date by the same surgeon on different organs/structures when an NCCI PTP edit exists between the CPT codes being reported.

Clinical scenario: The surgeon performs an ultrasound-guided steroid injection to the right shoulder and administers a steroid injection without ultrasound guidance to the right knee.

CPT codes reported for this date of service: 20611—Arthrocentesis, aspiration and/or injection, major joint or bursa (eg, shoulder, hip, knee, subacromial bursa); with ultrasound guidance, with permanent recording and reporting; 20610-XS—Arthrocentesis, aspiration and/or injection, major joint or bursa (eg, shoulder, hip, knee, subacromial bursa); without ultrasound guidance

Rationale: This modifier may be reported when two services that meet the separate structure rule are reported during the same session and an NCCI PTP edit exists. It typically will define a separate organ or structure. It may not be used to bypass an edit if a Column 1/Column 2 edit exists and there is overlap of work between the two procedures. A more specific modifier (RT, LT, 50, 59, and 76) is not appropriate for this code combination.

XP—Separate practitioner, a service that is distinct because it was performed by a different practitioner. This modifier should only be appended when an NCCI PTP edit exists between a code combination and two physicians (practitioners) of the same specialty and the same group on the same day. CMS considers physicians of the same specialty and the same group to be the “same physician.” The services would be expected to be performed during the same session.

Documentation must support the medical necessity of both surgeons (or other qualified healthcare provider) in the same group, same specialty performing the services independently.

Clinical scenario: After a motor vehicle accident, a patient with multiple musculoskeletal and other organ system injuries is transported to the emergency department. Dr. A assesses the patient, who is taken to the operating room. Dr. A performs an excisional débridement and ORIF of the right tibial shaft fracture; Dr A’s partner, Dr. B, performs an intermediate repair of a 10 cm complex laceration to the right thigh during the same session.

CPT codes reported for this date of service: Dr. A reports 27758—Open treatment of tibial shaft fracture (with or without fibular fracture), with plate/screws, with or without cerclage—and 11012-51—Débridement including removal of foreign material at the site of an open fracture and/or an open dislocation (eg, excisional débridement); skin, subcutaneous tissue, muscle fascia, muscle, and bone. Dr. B reports 13121-XP—Repair, complex, scalp, arms, and/or legs; 2.6 cm to 7.5 cm—and 13122-XP—Repair, complex, scalp, arms, and/or legs; each additional 5 cm or less (List separately in addition to code for primary procedure).

Rationale: An NCCI PTP edit exists between the codes reported by both providers when performed at the same site. The services were performed by the two different surgeons during the same surgical setting due to the patient’s underlying injuries and identified risk factors. A more specific modifier is not appropriate. Modifiers 50, 59, 76 and the Finger/Toe modifiers do not define the scenario.

XU—Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service. Append this modifier when two services are performed that typically would not be reported together but the special services allows the reporting of both services.

Clinical scenario: Surgeon performs right medial meniscectomy and removes a 7.5 mm loose body from the lateral compartment of the right knee.

CPT codes reported for this date of service: If submitting to CMS, the surgeon would report 29881 —Arthroscopy, knee, surgical; with meniscectomy (medial OR lateral, including any meniscal shaving) including débridement/shaving of articular cartilage (chondroplasty), same or separate compartment(s), when performed—and G0289-XU—Arthroscopy, knee, surgical, for removal of loose body, foreign body, debridément/shaving of articular cartilage (chondroplasty) at the time of other surgical knee arthroscopy in a different compartment of the same knee.

If submitting to a private payer, the surgeon would report 29881 and 29874-XU—Arthroscopy, knee, surgical; for removal of loose body or foreign body (eg, loose osteochondritis dissecans fragment, loose chondral fragment).

Rationale: The removal of a loose body, not documented as greater than 5 mm or removed via a separate incision/new portal is not reportable when performed during the same operative session as other knee procedures according to CPT and the AAOS CompleteGlobal Service Data for Orthopaedic Surgery. CPT code 29874 defines this service when reportable. CMS does not recognize CPT code 29874 in the presence of other arthroscopic knee procedures. Instead, CMS instructs the surgeon to report G0289 when the removal of the loose body is in a separate compartment of other arthroscopic knee procedures.

Final tips
Understanding NCCI PTP edits and paying particular attention to the NCCI Guidelines section of the Integumentary, Musculoskeletal, and Cardiovascular, Nervous, Radiology, and Medicine sections will be critical in determining when a modifier may bypass an edit on CMS Part B claims.

In addition to the Guidelines, the specific NCCI PTP edits discussed here will direct the surgeon and practice to ensure correct modifier application.

Remember, CMS assumes correct CPT coding. A modifier may only be appended if the coding rules are met and the services are considered non-overlapping. CMS states use of modifier 59 or an X modifier would be incorrectly reported if the services are coded correctly and an NCCI PTP edit is not in place.

Practices must be attentive to and monitor CMS, private payer, and local carrier instructions regarding the use of these modifiers.

Mary LeGrand, RN, MA, CCS-P, CPC, is a senior consultant with KarenZupko & Associates, Inc., who focuses on coding and reimbursement issues in orthopaedic practices. Information in this article has been reviewed by members of the AAOS Coding, Coverage, and Reimbursement Committee.