What is the difference between modifier 50 and 51?

Date Issued: 11/7/2014

CPT or HCPCS codes that are bilateral in intent or have bilateral in their description should not be reported with the bilateral modifier 50 or modifiers LT and RT because the code is inclusive of the bilateral procedure. CMS has updated its policies concerning the appropriate use and reporting of these modifiers.

For this policy, servicing practitioners reporting under the same Tax ID number, whether designated the same individual physician or another health care professional, are considered as one individual rendering the reported health care services.

Modifier 50 is used as a payment modifier, rather than an informational modifier. The addition of this modifier may affect payment depending on the procedure code and the BILAT SURG indicator.

Bilateral Indicator 0

Bilateral surgery rules do not apply to codes with a status indicator 0. The bilateral indicator is inappropriate for reasons such as:

• Physiology; is not a bilateral body part.
• The codes description states it is an existing bilateral procedure.
• The procedure is not commonly performed as bilateral. (These services do not meet the bilateral criteria.)

These codes should not be billed with modifiers 50, LT or RT.

The 150 percent payment adjustment for bilateral procedures does not apply.

Bilateral Indicator 1

Valid for bilateral billing claim submission. With the exception of CPT codes inherently bilateral by definition, EmblemHealth requires practitioners to report procedures performed bilaterally on one claim line with modifier 50 appended to the code (e.g., xxxxx-50, billed with 1 unit). Failure to report bilateral procedures in this way may result in incorrect processing of claims.

Reporting these bilateral-indicator-1 procedures with either LT or RT and 1 unit of service is appropriate only if the procedure is being performed unilaterally. If the procedure is performed bilaterally, modifier 50 should be appended to the procedure code with 1 unit of service.

The 150 percent payment adjustment for bilateral procedures applies.

Bilateral Indicator 2

These codes should not be billed with modifier 50. These codes are already established as being performed bilaterally:

• The code descriptors specifically state the procedure is bilateral.
• The code descriptor states the procedure may be performed either unilaterally or bilaterally.
• The procedure is usually performed as bilateral.

These codes should be billed with no more than 1 unit of service

Reporting these procedures with either an LT or RT modifier is appropriate if no unilateral CPT code exists. If a unilateral CPT code exists for the procedure, the unilateral CPT code should be reported with either the LT or RT modifier, with 1 unit of service. If no unilateral CPT code exists, modifier 52 should be appended to the bilateral CPT code to indicate a reduced service was performed.

The 150 percent payment adjustment for bilateral procedures does not apply.

Bilateral Indicator 3

These codes should be reported with the appropriate anatomical LT or RT modifier, with one unit of service for each. For example:

• xxxxx-LT, billed with 1 unit on one claim line
• xxxxx-RT, billed with 1 unit on a separate claim line

A practitioner can submit with modifier 50, if performed bilaterally.

The usual payment adjustment for bilateral procedures does not apply.

Bilateral Indicator 9

Concept does not apply. Bilateral surgery concept does not apply to codes with status indicator 9. These procedure codes should not be billed with modifiers 50, LT or RT (e.g., xxxxx, billed with 1 unit).

Modifier 50 – Correct Usage

Appropriate usage includes:

• Use modifier 50 when performing a bilateral procedure during one session and the Medicare Physician Fee Schedule Relative Value File (MPFSRVF), also known at the Medicare Physician Fee Schedule Database (MPFSDB) BILAT SURG indicator is 1 or 3.
• Report codes with a BILAT SURG indicator of 1 by appending modifier 50 and submit 1 unit of service on one line.
• Report codes with a BILAT SURG indicator of 3 either by appending modifier 50 using 1 unit of service on one line or when performing the procedure on bilateral body parts.
• Use modifier 50 to report bilateral procedures performed during the same operative session by the same physician in either separate operative areas (e.g., hands, feet, legs, arms, ears) or in the same operative area (e.g., nose, eyes, breasts).
• Do not bill modifiers LT and RT on the same service line when using modifier 50 to indicate a bilaterally performed procedure. Modifier LT or RT should be used to identify which of the paired organs was operated on. Billing procedures as two lines of service using the LT and RT modifiers is not the same as identifying the procedure with modifier 50. Modifier 50 is the coding practice of choice when reporting bilateral procedures.

Modifier 50 – Incorrect Usage

Inappropriate usage includes:

• Do not use modifier 50 when performing the procedure on different areas of the same side of the body.
• Do not use modifier 50 when the BILAT SURG indicator is 0, 2 or 9.
• Do not use modifier 50 when removing a lesion on the right arm and a lesion on the left arm. Use the RT and LT modifiers.
• Do not use modifier 50 with a procedure code that is described as bilateral, or unilateral or bilateral, in its CPT description.
• Do not report a bilateral procedure on two lines of service by appending modifier 50 to the second line of service.
• Do not submit modifier 50 on procedures for midline organs such as the bladder, uterus, esophagus and nasal septum.

Modifiers provide additional information about CPT® codes submitted and services rendered without changing the definition of the procedure code itself. Modifiers 51 and 59 are both used when multiple services are performed during a single encounter, but they serve different purposes. This Timely Topic covers the differences between these two modifiers.

Modifier 51 Multiple Procedures

Modifier 51 Multiple Procedures indicates that multiple procedures were performed at the same session. It applies to:

• Different procedures performed at the same session
• A single procedure performed multiple times at different sites
• A single procedure performed multiple times at the same site

Modifier 51 comes into play only when two or more procedures are performed. It is not to be used when a procedure is performed along with an Evaluation and Management (E/M) service.

There are instances where multiple procedures are performed but modifier 51 is not appropriate. Modifier 51 is not appended to add-on codes. For example, modifier 51 would not be appended to CPT code 64462 as it is an add-on code and would be used for any additional injection sites per its definition.

Certain codes are designated as Modifier 51 exempt. They are noted in CPT with the  symbol and are also listed in CPT’s Appendix E. Codes on this list that are most relevant to anesthesiology practices are:

Modifier 51 impacts payment. Many payers will apply a multiple procedure reduction to each additional procedure after the first reported code so be sure to list the most complex procedure first on your claims and append the modifier to any additional services reported when the situation calls for use of modifier 51.

Modifier 59 Distinct Procedural Service

Modifier 59 Distinct Procedural Service indicates that a procedure is separate and distinct from another procedure on the same date of service. Typically, this modifier is applied to a procedure code that is not ordinarily paid separately from the first procedure but should be paid per the specifics of the situation.

Indications for use of modifier 59:

• Different session or encounter on the same date of service
• Different procedure distinct from the first procedure
• Different anatomic site
• Separate incision, excision, injury or body part

Like modifier 51, modifier 59 should not be applied to an E/M service. Modifier 25 is used to denote a significantly separately identifiable E/M service. Like modifier 51, modifier 59 also has payment implications. Modifier 51 impacts the payment amount, and modifier 59 affects whether the service will be paid at all.

Modifier 59 is typically used to override National Correct Coding Initiative (NCCI) Edits. NCCI edits include a status indicator of 0, 1, or 9. A status indicator 1 identifies those code pairs not normally payable on the same date of service but may be paid in some circumstances when reported with an appropriate modifier (often modifier 59) and supported by documentation that demonstrates why the edit is not applicable and payment is warranted. For example, the modifier may be used when reporting anesthesia care and a post-operative pain procedure when the procedure meets the criteria that allows for it to be separately reportable. A previous Timely Topic gives additional examples of applying modifier 59 to anesthesia services.

CPT instruction also tells us that modifier 59 should not be used when a more appropriate modifier is available. For example, if a procedure is performed bilaterally, modifier 50 would be the more appropriate modifier.

Modifiers XE, XP, XS and XU became effective in January 2015 and were developed to provide more specific reporting in circumstances where modifier 59 may be used. At this time, these modifiers are not required but may be used instead of modifier 59 when appropriate to the clinical scenario being billed.

It is important to understand correct coding and modifier usage to ensure appropriate payment for your services. As always, make sure you are familiar with instruction from your local carriers and ensure your documentation supports what and how you report your services.

The following is a quick reference to summarize when to use modifier 51 and 59:

References/Additional Information: