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A Guide to Applying Common Physical Therapy Modifiers

medicare pt modifiers

Billing in physical therapy comes with its own set of challenges, especially with the wide range of CPT codes and Medicare PT modifiers that need careful attention. 

Managing these codes is crucial to ensure every service that you provide is properly documented and reimbursed. Familiarizing yourself with these essential modifiers not only helps reduce billing errors but also streamlines claims processing, ultimately boosting your clinic’s revenue and efficiency.

In this blog, we’ll break down the most common Medicare PT modifiers, explain their practical applications, and provide real-world scenarios to illustrate their importance. 

What are Physical Therapy Modifiers?

Medicare Physical Therapy Modifiers are alphanumeric codes added to CPT (Current Procedural Terminology) codes during billing. These modifiers play a crucial role by providing extra details about the treatment, making the claims process smoother and more efficient. They add necessary context, ensuring that services are clearly documented and accurately reimbursed.

For example, the GA modifier informs payers that a service ordered may not be covered by the patient’s insurance, signaling potential out-of-pocket expenses. 

Similarly, the GN modifier specifies that the service was provided under a speech therapy plan of care, clarifying the billing for accurate processing.

Commonly Used Physical Therapy Modifiers and Their Uses

Modifiers are pivotal in ensuring accurate billing and reimbursement for physical therapy services. Here's a look at some important modifiers and how they are applied in practice:

1. KX Modifier

The KX modifier is essential for documenting services that exceed Medicare's therapy threshold, validating the need for continued treatment with appropriate patient medical record documentation. 

Example: If a patient recovering from a hip fracture reaches the therapy threshold but still requires additional sessions, the therapist would use the KX modifier to justify ongoing care.

Use: The KX modifier is used when a medicare beneficiary nears the financial limit for physical therapy, occupational therapy, or speech-language pathology. It helps justify the need for continued care!

Also, read about The Medicare therapy threshold and KX modifier.

2. XE Modifier

The XE modifier, or Separate Encounter, is used when a distinct service occurs during a separate encounter on the same date of service (DOS). 

For Example, A patient visits a physical therapist in the morning for a routine follow-up and returns later that day for a different issue. The afternoon session would be billed with the XE modifier, indicating a unique encounter.

Use: The XE modifier, or Separate Encounter, indicates that a service occurred during a distinct visit on the same day. It clarifies that multiple services provided to a patient are separate and justifies billing for each encounter.

3. GP Modifier

The GP modifier indicates that a physical therapist performed a service. 

Example: If a physical therapist administers therapeutic exercises (CPT code 97110) in an outpatient setting, the billing will reflect this as 97110-GP, clearly identifying the provider.

Use: The GP modifier indicates that a physical therapist has provided a service. It is used in billing to specify the provider type, ensuring clarity and proper reimbursement for therapy services rendered by a licensed physical therapist.

4. CQ Modifier

The CQ modifier specifies that services were provided by a Physical Therapy Assistant (PTA). 

Example: When a PTA treats a patient during a routine session, the CQ modifier would be appended to all associated charges, ensuring clarity in billing. The supervising PT must co-sign the PTA's documentation.

Use: The CQ modifier indicates that services were provided by a Physical Therapy Assistant (PTA). It ensures clear billing by identifying the PTA's role while requiring the supervising Physical Therapist to co-sign the documentation for proper reimbursement.

5. Modifier 59

Modifier 59 signifies that a distinct service or procedure was performed separately from another non-evaluation and management service. This is essential for compliance with the National Correct Coding Initiative.

Example: If a physical therapist treats a patient with an ankle sprain and bills for both manual therapy (CPT code 97140) and therapeutic activity (CPT code 97530) on the same day, the therapist will apply the Modifier 59 to the 97530 code to ensure payment for both services.

Use: Modifier 59 indicates that a distinct service or procedure was performed separately from another non-evaluation and management service on the same date. It helps ensure compliance with the National Correct Coding Initiative and supports billing for multiple services that may otherwise be bundled together.

Modifier 59 is significant for addressing National Correct Coding Initiative (NCCI) edit pair services. It indicates that two services billed on the same date are distinct and separate, even if they may otherwise be considered bundled together. To use modifier 59 appropriately, the following requirements must be met:

  • Distinct Services: The services must be different and performed independently. Documentation should support that they were necessary and not part of the same procedure.
  • Same-Day Services: The services must occur on the same service date.
  • No Other Modifier Applicable: Modifier 59 should only be used when no other modifiers are more appropriate to convey the distinct nature of the services.

6. GA Modifier

The GA modifier indicates that a required Advance Beneficiary Notice of Noncoverage (ABN) is on file for a service deemed not medically necessary. 

Example: If a Medicare patient, having reached a functional plateau after six weeks of post-op therapy, wishes to continue with maintenance sessions, the GA modifier allows the clinic to bill secondary insurance or charge the patient directly.

Use: The GA modifier signifies that an Advance Beneficiary Notice of Noncoverage (ABN) is recorded for a service that Medicare has determined as - not medically necessary. This modifier enables providers to bill either secondary insurance or the patient directly for these services, ensuring transparency in billing for treatments that may not be covered.

7. XP Modifier

The XP modifier denotes that a different practitioner provided a service. 

Example: If a patient has a morning session with a physical therapist for a specific issue and later sees an occupational therapist for separate services, the second session would be billed with the XP modifier to indicate it as a distinct encounter, ensuring proper billing.

Use: The XP modifier denotes that a different practitioner provided a service. It is used in billing to indicate that the patient received care from multiple providers for separate issues, ensuring accurate billing and proper reimbursement for each distinct encounter.

These modifiers streamline the billing process and enhance the clarity and accuracy of healthcare documentation in physical therapy practices.

8. GO Modifier

The GO modifier is used for services provided under an occupational therapy plan of care. This modifier is essential for distinguishing occupational therapy services from physical and speech therapy in Medicare claims, helping to avoid billing errors and ensure correct reimbursement.

Example: An occupational therapist is working with a patient recovering from a hand injury. The therapist uses adaptive equipment to improve the patient’s fine motor skills and dexterity (CPT code 97535). The GO modifier is appended to the CPT code to specify that the service is part of an occupational therapy plan, clarifying its purpose and allowing Medicare to process the claim accurately.

Use: Attach the GO modifier to all services billed under an occupational therapy plan to ensure clear differentiation from other therapy types and compliance with Medicare billing regulations.

9. GN Modifier

The GN modifier is designated for services provided under a speech-language therapy plan of care. This modifier is essential to clarify that the therapy is focused on speech or language, differentiating it from other therapeutic services in claims.

Example: A speech therapist assists a patient recovering from a stroke, providing exercises to improve swallowing abilities (CPT code 92526). Since this treatment is specific to speech therapy, the GN modifier is added to the code, indicating the nature of the service and ensuring that it’s processed under the correct therapy category for Medicare.

Use: Apply the GN modifier to any service billed under a speech-language therapy plan, ensuring accurate categorization in Medicare’s system and preventing billing issues.

10. 96 Modifier

The 96 modifier is used to identify services provided for habilitative purposes. This means that the therapy is aimed at helping the patient learn new skills rather than restoring skills that were previously lost due to an illness or injury.

Example: A child with a congenital condition receives developmental therapy to build core functional skills, like coordination and basic motor control, using CPT code 97535. Since this therapy is habilitative and intended to teach new abilities rather than recover lost ones, the 96 modifier is appended to indicate the service’s unique purpose.

Use: Use the 96 modifier for habilitative services to specify that the treatment is designed for skill acquisition rather than rehabilitation, ensuring correct processing and documentation in Medicare’s billing system.

11. 97 Modifier

The 97 modifier is applied to services that focus on rehabilitative therapy. This includes treatments that aim to restore function or skills lost due to illness, injury, or surgery.

Example: A patient who experienced a rotator cuff injury undergoes physical therapy to regain shoulder mobility (CPT code 97110). Since the therapy is intended to rehabilitate a skill previously lost, the 97 modifier is added to clarify that the treatment’s focus is rehabilitative. This helps Medicare accurately interpret the purpose of the therapy and process the claim.

Use: Attach the 97 modifier to any rehabilitative service, differentiating it from habilitative care and ensuring the claim is aligned with Medicare’s requirements.

12. CO Modifier

The CO modifier indicates that a service was provided by an Occupational Therapy Assistant (OTA) under the supervision of an occupational therapist. This modifier is crucial to distinguish assistant-provided services from those performed directly by licensed occupational therapists.

Example: An Occupational Therapy Assistant works with a patient to improve their strength through adaptive exercises (CPT code 97530). Since the OTA is delivering the service, the CO modifier is appended to the code, indicating the assistant’s involvement and the supervising occupational therapist’s role.

Use: Apply the CO modifier for services provided by an OTA to maintain transparency in billing and meet Medicare’s requirements for assistant involvement in patient care.

13. GA Modifier

The GA modifier is used when an Advance Beneficiary Notice of Noncoverage (ABN) is on file for a service Medicare may not cover. This modifier indicates that the patient has been informed about the potential cost they may incur if Medicare denies the service.

Example: A patient chooses to continue physical therapy sessions for maintenance after meeting their functional goals. The therapist has provided an ABN to inform the patient that these sessions may not be covered by Medicare. The GA modifier is added to the claim to indicate that the patient is aware of potential out-of-pocket expenses and has signed the ABN.

Use: Use the GA modifier when an ABN is necessary to signify that the patient has been informed of the service’s non-coverage by Medicare and has acknowledged their financial responsibility.

14. GX Modifier

The GX modifier is applied when a voluntary ABN is on file for services that Medicare never covers. This modifier shows that the patient has been informed and has agreed to pay out of pocket for these services.

Example: A patient chooses a wellness massage as part of their therapy, which Medicare does not cover. The therapist obtains a voluntary ABN from the patient and appends the GX modifier to the claim. This indicates that the patient signed an ABN acknowledging they’ll pay for the service independently.

Use: Use the GX modifier for services Medicare doesn’t cover, even if there is no requirement for an ABN. The GX modifier is useful for documenting a patient's acknowledgment of liability for services not covered by insurance.

15. GY Modifier

The GY modifier is used when billing for services Medicare explicitly excludes from coverage, and no ABN is on file. This modifier signals that the service is not covered and no ABN was required or provided.

  • Example: A physical therapist provides acupuncture, a service Medicare doesn’t cover, and adds the GY modifier to indicate its exclusion. This modifier ensures the claim reflects Medicare’s policy on non-covered services and bypasses the need for an ABN.
  • Use: Apply the GY modifier for statutorily excluded services, allowing Medicare to process the claim correctly as a non-covered item without requiring an ABN.

16. GZ Modifier

The GZ modifier is used to indicate that no ABN is on file and that Medicare is likely to deny coverage for the service. This modifier is applied when the provider did not obtain an ABN for a service that is probably non-covered.

  • Example: A physical therapist provides dry needling but fails to issue an ABN to the patient, even though Medicare doesn’t typically cover this service. The GZ modifier is appended to the claim, acknowledging that no ABN was given and that Medicare is expected to deny the claim.
  • Use: Use the GZ modifier when a non-covered service is provided without an ABN. This modifier informs Medicare of the lack of patient notification, likely leading to denial.

Here’s a video on “KX Modifier-Adopting Appropriate Claim Denials Management Systems” by National Government Services. Check it out! 

KX Modifier-Adopting Appropriate Claim Denials Management Systems

Practical Scenarios and Modifier Application

Understanding how to apply CPT codes and modifiers in real-life cases can clarify proper billing and ensure accurate reimbursement. Here’s a look at how CPT codes are applied in different scenarios involving both a physical therapist and a physical therapist assistant.

Scenario #1: Patellofemoral Pain Treatment

During an appointment for a patient with patellofemoral pain, your physical therapist assistant (PTA) may handle part of the session—in this case, providing 13 minutes of therapeutic exercise  (CPT 97110). Afterward, you, as the physical therapist (PT), might take over for 22 minutes of manual therapy  (CPT 97140) and then conclude with another 15 minutes of therapeutic exercise.

Claim Submission:

To ensure accurate billing, include the correct therapy modifiers on your claim: GP for physical therapy, GO for occupational therapy, and GN for speech-language pathology. In this scenario, you’d attach the GP modifier to all services provided during the session. Since the PTA delivered a significant portion of the therapeutic exercise, the CQ modifier is also required. This modifier applies whenever a therapy assistant provides over 10% of service, so you’d attach it to one of the two units of CPT 97110.

Final Modifiers with Procedure Codes:

  • CPT 97140: GP
  • CPT 97110 (1 unit): GP
  • CPT 97110 (1 unit): GP, CQ

Let us consider another example. 

Scenario #2: Adhesive Capsulitis Treatment

After recovering from a broken arm, a Medicare patient faces a new challenge: adhesive capsulitis of the shoulder. They seek relief and turn to a physical therapist (PT) for treatment. During one session, the PT skillfully combines several therapies:

  1. Manual Therapy (CPT 97140) to ease shoulder tension.
  2. Therapeutic Activities (CPT 97530), where the patient practices reaching up and lifting lightweight objects.
  3. ADL Training (CPT 97535) involves exercises like holding the arm to simulate brushing teeth and opening cabinets.

The therapist provides dry needling (CPT 20560) in the affected area to wrap up the session. However, a voluntary Advance Beneficiary Notice (ABN) is issued since Medicare doesn't cover this service.

The Claim Submission:

When it's time to submit the claim, the PT needs to add the correct modifiers:

  • CPT 97140: GP
  • (Indicating a PT provided the service)

For the therapeutic activities and ADL training, since CPT 97530 and CPT 97535 form an NCCI edit pair, they can both be billed with one service requiring a 59 modifier to highlight their distinct nature.

Lastly, the dry needling procedure requires the GX modifier to indicate it's a non-covered service for Medicare.

Final Modifiers with Procedure Codes:

  • CPT 97140: GP
  • CPT 97530: GP, 59
  • CPT 97535: GP
  • CPT 20560: GP, GX

Scenario #3: Post-Hip Arthroplasty Rehabilitation

A Medicare patient undergoes a left total hip arthroplasty. In their outpatient therapy session, the PT starts with 9 minutes of neuromuscular education (CPT 97112), and then the PTA oversees 6 minutes of exercises. The PT returns to guide gait training (CPT 97116) and functional testing (CPT 97750). The PT later realizes the patient has exceeded their annual therapy threshold.

The Claim Submission:

Add the GP modifier since the services are billed under the PT's name. The PTA's contribution to neuromuscular education means you'll also apply the CQ modifier. Finally, since the treatment is medically necessary despite the threshold being exceeded, use the KX modifier.

Final Modifiers:

  • CPT 97112: GP, CQ, KX
  • CPT 97116: GP, KX
  • CPT 97750: GP, KX

Scenario #4: Wheelchair Training for Ehlers-Danlos Syndrome

A Medicare patient with Ehlers-Danlos syndrome is seeing an occupational therapist (OT) for joint hypermobility. The OT begins with 10 minutes of neuromuscular reeducation (CPT 97112) before conducting wheelchair training (CPT 97542) alongside a COTA (Certified Occupational Therapists Assistant) for 11 minutes. The COTA continues training for an additional 12 minutes. At the end of the appointment, the patient requests manual therapy (CPT 97140), which the OT believes isn't necessary, so they obtain an ABN.

Also, read about Occupational Therapy acronyms and abbreviations.

Claim Submission:

Since the OT is submitting the claim, add the GO modifier. The COTA's contribution requires the CO modifier for one unit of wheelchair training. Finally, since manual therapy is not deemed necessary, apply the GA modifier.

Final Modifiers:

  • CPT 97112: GO
  • CPT 97542 (1 unit): GO
  • CPT 97542 (1 unit): GO, CO
  • CPT 97140: GO, GA

The Scenario #5: Upper-Cervical Neck Pain Treatment

A Medicare patient visits a PT for upper-cervical neck pain, suspecting they've hit their therapy threshold. The PT provides manual therapy (CPT 97140) for the neck, followed by ergonomic and postural adaptations (CPT 97537). To wrap things up, the PT performs dry needling (CPT 20560) but doesn't collect an ABN.

The Claim Submission:

Since a PT is billing the services, add the GP modifier because the patient has surpassed the therapy threshold, including the KX modifier for the services Medicare covers. Since dry needling isn't covered and no ABN was collected, use the GY modifier for that service.

Final Modifiers:

  • CPT 97140: GP, KX
  • CPT 97537: GP, KX
  • CPT 20560: GY

The Scenario:6. UHC Community Plan Ankle Sprain Treatment

A UHC Community Plan patient visits for physical therapy due to an ankle sprain. The patient receives 15 minutes of manual therapy and 30 minutes of therapeutic activities.

The Claim Submission:

Usually, you'd use the GP modifier. However, the UHC requires 97 for rehabilitative services.

Final Modifiers:

  • 97140 (1 unit): GP, 97
  • 97530 (2 units): GP, 97

Now that we have understood certain different scenarios where CPT codes can be applied, lets concentrate on the common billing mistakes that occur and how can they be avoided.  

Common Billing Mistakes and How to Rectify Them

Billing for physical therapy services can be tricky, but navigating CPT modifiers can help avoid common errors. Here's how to avoid the most frequent pitfalls!

1. Misunderstanding Payer Policies

Each insurance provider has its rules for modifier use, and misinterpreting these can lead to billing issues. It is essential to regularly review the billing policies of top payers and seek clarification when necessary. Better safe than sorry!

2. Failing to Document Justification

Modifiers require proper justification in documentation, as claims can be denied if a review reveals insufficient support for the modifier. It is important to ensure that notes clearly back up the treatment provided and are directly tied to the patient's condition.

3. Incorrect use of Medicare PT Modifier

A common mistake in medical billing is the misuse of modifiers, such as incorrectly applying modifier -59 (Distinct Procedural Service) when the services provided are not genuinely distinct. This misuse can lead to significant claim denials, as payers may interpret the services as overlapping rather than separate. 

Spry reduces claim denials with accurate documentation and streamlined coding, including built-in compliance checks for payer rules. Keep clear, complete records and strengthen your claims—Discover Spry today!

4. Overlooking New Modifiers

CPT codes and modifiers are updated annually, and using outdated codes can lead to billing errors, claim denials, or delayed reimbursements. Staying informed on these updates is crucial to avoid such costly mistakes. 

Subscribing to newsletters from industry resources like Spry and attending coding seminars can help you keep up with these changes. Spry’s platform simplifies this process by providing regular updates, built-in coding checks, and resources that reduce billing issues before they arise. Schedule a free demo with Spry to see how it can help streamline your billing and keep your practice fully complaint.

Consequences of Inappropriate Use of Medicare PT Modifiers

Modifiers play a crucial role in accurately communicating exceptional circumstances in billing, but improper use can lead to significant consequences for physical therapists. Here are some common mistakes to avoid and their potential impacts:

  • Random Assignment: Verify modifiers before assigning them to avoid errors that could lead to claim denials and delayed reimbursements.
  • Unbundling Codes: Avoid using modifiers to unbundle services unnecessarily, as it’s unethical and can lead to audits and compliance issues.
  • Modifier Overload: Applying unnecessary modifiers can flag claims for review. Use only those relevant to the treatment scenario to avoid complications.
  • Unsupported Bypass: Don’t add modifiers to bypass edits without proper documentation, as this can lead to claim denials and disputes.
  • Higher Reimbursement Manipulation: Avoid using modifiers to inflate reimbursement, as this undermines ethical billing and risks compliance penalties.
  • Missing Modifiers: Not including required modifiers for exceptional cases can result in lost revenue and missed reimbursements.
  • Contradictory Modifiers: Ensure modifiers align with CPT definitions and payer policies to avoid claim rejections and compliance issues.
  • Mislinking Modifiers: Link each modifier accurately to its procedure code to prevent confusion, delays, or claim rejections.

By being mindful of these common mistakes and their consequences, physical therapists can enhance their billing accuracy, ensure compliance, and maintain a steady revenue stream.

Conclusion

Medicare PT modifiers play a crucial role in PT billing. They make sure that physical therapists receive payment for the services they provide while giving assurance of compliance. However, using the medicare pt modifier must always be supported by documentation reflecting patient care. 

By mastering Medicare PT modifiers, therapists can avoid claim denials and billing errors, ensuring accurate reimbursement—an advantage also supported by Spry’s billing software.

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