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The Ultimate Physical Therapy Modifier Quiz

Physical therapy modifiers can be tricky. Use this fun quiz to get you and your staff up to speed on when it’s best to apply them.

Ryan Giebel
5 min read
October 11, 2022
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Times are tough for the rehab therapist who wants to make an honest dollar helping others. Reimbursements are down and continue to decline while costs are on the rise in nearly every facet of running a business. What’s more, Medicare continues to propose and implement new rules that only make the billing landscape even murkier. As such, there’s no time like the present to refresh our billing knowledge—particularly in the hopes of warding off dreaded denials so that every hard-earned dollar finds its way back to you (and not the auditor). And where better to start than with physical therapy modifiers?

What are physical therapy modifiers anyway?

Before we begin testing your modifier mettle, let’s briefly review what a modifier is and why they are important to rehab therapy billing. Essentially, modifiers are used to add information and details otherwise not included in a CPT code without changing the specific code. The modifiers act to add to the story and paint a clearer picture for payers. Below is a list of modifiers most relevant to the rehab therapy industry:

And with that, let’s jump headfirst into our mighty physical therapy modifier quiz.

Get all the physical therapy modifier information you need—and then some—with our incredibly detailed physical therapy billing guide.

Scenario 1

An occupational therapist is working to perform an audit of outgoing billing tickets from their interprofessional rehab clinic. They come across one patient—who is seeing both an occupational and physical therapist for stroke rehabilitation—where the billing claim for services provided by the PT were rejected. The PT saw the patient first for 55 minutes of direct treatment time and was present in the session for a total of 63 minutes. The CPT codes applied were two units (30 minutes) of therapeutic exercise (97110) and two units (25 minutes) of manual therapy (97140). Within the bill, the GN modifier is applied to the physical therapy services, which includes two units of therapeutic exercise, one unit of therapeutic activity, and one unit of manual therapy. What is wrong with the modifiers and/or codes applied to this scenario?

Answer 1

Presently, the GN modifier attached corresponds to speech-language pathology service codes. Therefore, this service requires a GP modifier instead as it corresponds to physical therapy services. Medicare would inevitably kick back the claim with a rejection. The correction here is a relatively simple one, but to miss it could mean a major loss of dollars.

Scenario 2

A physical therapist and clinic owner recently hired a new physical therapist assistant to help them manage their burgeoning Medicare beneficiary caseload. The PT has never worked with a PTA before, so they have opted to start the process by sharing patients/caseloads. The PT plans to do the more high-level treatments and manual interventions with patients and then allow the PTA to wrap up treatment with less advanced exercises and/or biophysical agents to complete treatment with the patient. 

In one such session, the PT completed 12 minutes of lumbar mobilizations (97140) followed by 15 minutes of neuromuscular reeducation (97112) for core stability. The PTA finished the session with an additional 20 minutes of therapeutic exercises (97110) followed by moist heat and interferential current electrical stimulation (paired) for fifteen minutes. In this scenario, what would the proper units and associated modifiers be for billing?

Answer 2

The associated codes would be manual therapy (97140) and neuromuscular reeducation (97112) both with a GP modifier for the PT treatment. There would also be a code for therapeutic exercises (97110) with a GP and CQ code as this was provided by the PTA. Finally, there would also be associated codes for moist heat (97010) and unattended electrical stimulation (G0283) with the GP modifiers attached for these services. 

Scenario 3

The PT and PTA from above have started to get a feel for each other’s styles and skill sets. The PT now trusts the PTA to handle almost all treatment methods that are allowed by the state’s practice act for PTAs. As such, the PT has created a separate schedule for the PTA. In one such instance, the PT is on the phone with a doctor at the front desk while the PTA carries on with treatment of their patient. The PTA provides 25 minutes of therapeutic exercises (97110) followed by another 15 minutes of neuromuscular reeducation (97112) for posture and balance. Now that the PTA has their own caseload, what would the billing claim look like?

Answer 3

So long as supervision is provided, the CQ modifier must always be attached to services rendered by a PTA when the service minutes are 10% or more of the service treatment time. Therefore, this bill will include two units of therapeutic exercises (97110) and one unit of neuromuscular reeducation (97112) with the modifiers GP and CQ attached to both.

Scenario 4

A physical therapist is providing treatment to a Medicare beneficiary with a recent reverse total shoulder replacement. Presently, this patient complains of an inability to lift a coffee mug to their mouth as well as difficulty brushing their teeth with the involved upper extremity. The treating physical therapist started today’s session with therapeutic activities (97530) to simulate reaching and lifting lightweight objects from waist to shoulder height. During the same treatment session the PT also implements self-care tasks (97535) like holding the arm at shoulder height for sustained periods and practicing opening jars of various sizes. The clinic’s biller submitted the claim with the affixed GP modifier, but the claim was denied—why?

Answer 4

Although the GP modifier was correct, the claim was denied due to the absence of modifier 59. Using both the codes 97530 and 97535 results in an NCCI edit pair. To show Medicare that both these codes were necessary, separate, and distinct, one of the codes will need modifier 59 affixed to it. 

Scenario 5

A physical therapist works in a clinic that sees a large commercial insurance and athletic patient population. As a result, cutting-edge treatments like dry needling have become a mainstay at their practice. A medicare patient walks in and requests dry needling for their chronic plantar fasciitis. The patient asks if dry needling is covered under Medicare, and how best to proceed with care. The therapist explains to them that an advanced beneficiary notice (ABN) is recommended, but not required. If the patient chooses to sign an ABN, what modifiers would you use to bill the dry needling service?

Answer 5

Medicare recognizes dry needling as within the scope of practice for PTs, but it is not a covered service. An advanced beneficiary notice (ABN) for non-covered services is recommended, but not required. If the patient does end up signing the ABN, the therapist will affix the GP and GX modifiers to the dry needling code.

Scenario 6

The patient from the previous scenario has agreed to continue with dry needling treatment in conjunction with traditional PT services, but declined to sign the ABN. In the first session, the physical therapist provides a low complexity initial evaluation (97161) followed by dry needling (20560 or 20561) accompanied by neuromuscular reeducation (97112) for foot motor control and posture. What would the proper billing claim with modifiers include for this initial visit?

Answer 6

The initial evaluation was low complexity so code 97161 with modifier GP. The dry needling treatment will require code 20560 or 20561—depending on the number of muscles needled—with modifiers GP and GY (as there is no ABN on file). Lastly, neuromuscular reeducation (97112) just needs to be affixed with modifier GP. 

As dry needling is not a covered service, a recommended out-of-pocket payment would be applied to the patient, as well.

Scenario 7

A Medicare beneficiary with rheumatoid arthritis is seeing an occupational therapist to help manage their mobility deficits due to the advancement of their disease. Specifically, the patient has increased difficulty with ambulation and recently purchased a wheelchair (per their physician’s recommendation), which the OT plans to help train them on. During the first appointment with the wheelchair, the OT performs neuromuscular reeducation (97112) for 10 minutes, and then the OT and a COTA provide wheelchair training (97542) in tandem for 11 minutes. The OT steps away, and the COTA provides 12 more minutes of wheelchair training. 

At the end of the appointment, the patient requests manual therapy (97140) to temporarily soothe their pain in the lumbar spine region. The OT agrees, though they note that they don’t believe the manual therapy is medically necessary and ask the patient to sign an ABN.


Nothing like a few additional curve balls to throw into this mix, so let’s break this one down. Starting with medical necessity, the treatment to the lumbar spine is outside the scope of this particular plan of care (POC), so a signed ABN would be necessary for both reasons. The billed units for 97112 and 97542 would have a GO modifier attached to distinguish services provided by the OT while the second unit for 97542 done by the COTA will require GO and CO modifiers to distinguish services provided by a COTA.

Scenario 8

A physical therapist is providing care for a patient who works as a mechanic and complains of a stiff neck that worsens throughout the day, especially during sustained postures while looking up. In addition, the patient also reports a gradual worsening of pain and tingling into the right arm. The pain into the arm is described as lancinating and is intermittent—again, worsening while looking up for prolonged periods of time. In the initial follow up visit after the evaluation, the PT decides to bill for one unit of neuromuscular reeducation (97112) working on postural awareness and strength, one unit of manual therapy (97140) to reduce myofascial pain and tension in the lower cervical and upper thoracic regions, and one unit of mechanical traction (97012) to reduce the effects of cervical radiculopathy. What modifiers would be appropriate in this scenario?

Answer 8

The key in this scenario is that the physical therapist felt there was a need for both cervical traction and manual therapy, which were completed in similar regions but for different purposes and were distinct from one another. Therefore, both 97140 and 97012 need a GP modifier while modifier 59 would need to be applied for cervical traction (97012).

Scenario 9

A Medicare beneficiary is seeing a PT for a case of upper-cervical neck pain that they believe is triggering major headaches. They mention at the beginning of their appointment that they think they’ve surpassed their therapy threshold. The PT proceeds with the appointment and provides joint and soft tissue mobilization for the cervical spine (97140) before letting the patient meet with a PTA to instruct on ergonomic and postural adaptations (97537) and performing postural awareness activities (97112). Before concluding the session, the PT performs dry needling to the affected area (20560), but does not collect an ABN. 

Answer 9

Let’s also break this one down:

  • Since this primary treatment was provided by a PT and the claim will be billed under their name, the GP modifier must be affixed to the claim form. 
  • Because the patient has surpassed the annual therapy threshold and the PT is assured this is medically necessary, affix the KX modifier to the services that Medicare will pay for (i.e., 97140 and 97537). 
  • Two services were also performed by a PTA, so 97537 and 97112 will need modifiers GP and CQ affixed to the PTA. 
  • Finally, because dry needling is not a covered service under Medicare and the PT did not collect an ABN, the GY modifier will also need to be affixed to 20560. 

Scenario 10

A physical therapist has been seeing a Medicare beneficiary for low back pain, but they were recently hospitalized with atrial fibrillation. The patient returns to therapy with orders from their doctor to resume therapy for their low back and monitor cardiac symptoms. The physical therapist completes a re-evaluation (97164) taking vitals and re-assessing the status of initial evaluation goals. To conclude the session, the PT instructs in proper transfer technique from low chairs to protect the low back as well as to not burden blood pressure in position changes. The PT also performs manual therapy techniques (97140) to the lumbar spine region for pain reduction after sleeping in a hospital bed. The physical therapist plans to charge for a re-evaluation (97164), therapeutic activity (97530), and manual therapy (97140), but is unsure if they need to attach modifier 59 to the claim. What is the correct answer?

Answer 10

Prior to 2021, therapeutic activity and manual therapy would have needed modifier 59 when billed together, and both therapeutic activity and manual therapy would have each needed modifier 59 to be paired with a re-evaluation. But, this is no longer the case. Due to the high volume of claim denials and confusion associated with re-evaluations, CMS has agreed to reimburse paired services without use of modifier 59 for certain combinations. As such, this claim can be submitted with just the GP modifier for all three codes.

Navigating the billing landscape never seems to get easier, nor does CMS’ insistence on using letters and numbers to describe any variation of coding regulations. But there is a light at the end of the tunnel—billing software continues to evolve and increased automation will continue mitigating billing errors associated with these codes (thus helping you get every dime you deserve from payers). However, keeping staff up to date on best billing practices is also integral to ensuring your clinic’s success, so we encourage you to share this quiz with your therapists during your next staff meeting!

If you have any further questions about these modifiers, feel free to leave them in the comments below. Or, better yet, register for our annual live billing Q&A webinar, taking place on October 20 at 9:00 AM PDT.


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