What Is CPT Code 64490

CPT 64490 refers to:

Injection(s), diagnostic or therapeutic agent, paravertebral facet (zygapophyseal) joint (or nerves innervating that joint) with imaging guidance (fluoroscopy or CT), cervical or thoracic; single level.

It is used when a physician performs a facet joint injection or medial branch nerve block in the cervical or thoracic spine, guided by fluoroscopy or CT. The procedure may be for either diagnostic purposes (to identify the source of pain) or therapeutic (to relieve pain).

Understanding the Code Family: 64490 to 64492

CPT 64490 is the primary code for the first level of injection in the cervical or thoracic spine. Additional levels are billed using add-on codes:

• +64491 – Second level (cervical or thoracic)
• +64492 – Third and additional levels (cervical or thoracic)
  
  

For injections in the lumbar or sacral region, different codes apply:

• 64493 – First level lumbar or sacral
• +64494 – Second level
• +64495 – Third and additional levels
  
  

Add-on codes must always be billed in conjunction with a primary code. Never report them alone.

When and Why CPT 64490 Is Used

Facet joint injections serve two main purposes:

1. Diagnostic Use

To confirm whether the facet joint is the source of pain.

2. Therapeutic Use

To treat pain and inflammation when conservative treatments have failed.

In both cases, accurate reporting and documentation are crucial for meeting payer requirements and supporting medical necessity.

Key Documentation Elements for CPT 64490

To support proper billing, the following must be documented in the medical record:

• Patient history and physical exam
• Duration and severity of pain
• Failed conservative treatments
• Pain scale or disability score
• Imaging guidance (fluoroscopy or CT)
• Spinal levels and laterality injected
• Medications used
• Patient response to prior procedures (if applicable)
  
  

Missing or vague documentation is a top reason for claim denials under CPT 64490.

Imaging Guidance: A Requirement You Cannot Skip

Imaging guidance is not optional. CPT 64490 includes:

• Fluoroscopy or CT as part of the service
• Contrast injection if used
• Imaging is bundled and not separately billable
  
  

If no imaging is used, 64490 is not valid, and the claim will likely be denied. Clearly state imaging in the procedure note.

ICD 10 Codes That Support CPT 64490

Billing CPT 64490 without an appropriate diagnosis code will almost always trigger a denial.

Common ICD-10 codes used with CPT 64490:

• M54.2 – Cervicalgia
• M54.6 – Pain in the thoracic spine
• M47.812 – Cervical spondylosis without myelopathy or radiculopathy
• M47.814 – Thoracic spondylosis without myelopathy or radiculopathy
• M54.89 – Other dorsalgia
• M53.82 – Facet joint syndrome (if supported by payer policies)
  
  

Always review payer-specific LCD or coverage guidelines to ensure the diagnosis is considered medically necessary.

Modifier Use for 64490 Billing

One of the biggest challenges in billing CPT 64490 is correct modifier usage, especially for bilateral procedures.

Unilateral Injection (One Side)

• Report 64490 without a modifier
  
  

Bilateral Injection (Both Sides Same Level)

• Use modifier 50
• Example: 64490-50
  
  

Multiple Levels

• Use +64491 for the second level
• Use +64492 for third or additional levels
• For bilateral additional levels, some payers require x2 units rather than modifier 50
  
  

RT and LT Modifiers

• Some payers require RT and LT on separate lines instead of modifier 50
• This is common in ASC facility claims

Always check the payer’s rules. Modifier requirements can vary by place of service and insurance plan.

Medicare Billing Guidelines for 64490

Medicare generally follows CPT instructions but has specific policies codified in Local Coverage Determinations (LCDs).

Key Medicare Rules:

• Modifier 50 is used for bilateral injections
• Add-on codes +64491 and +64492 should not use modifier 51
• Facet joint procedures without imaging are not covered
• Medicare tracks the number of sessions per region annually
• Some regions require specific documentation forms or prior authorization
  
  

Reimbursement Rates for CPT 64490

Reimbursement for CPT 64490 can vary widely depending on the payer contract place of service and geographic location. National average figures help providers benchmark expected payment amounts and prepare for claims submission and contract negotiation.

According to recent fee schedule data CPT 64490 has the following national average reimbursement ranges from major payers. These are typical reimbursements under fee‑for‑service or negotiated provider contracts and not patient charges. 

Notes on Medicare Reimbursement

Medicare’s physician fee schedule lists allowable amounts by locality. National figures for interventional pain procedures like facet injections tend to be lower than commercial plans and vary by practice setting. Medicare pays based on the Physician Fee Schedule and may have different rates for facility and non‑facility settings. 

Why Payment Amounts Vary

Reimbursement variability reflects:

• Place of service — Office procedures usually have different payment rates than Ambulatory Surgery Centers (ASC) or Hospital Outpatient Departments (HOPD)
  
  
• Payer contract terms — Each insurer negotiates unique fee schedules with providers
  
  
• Geographic differences — Regional Medicare localities have different allowable rates
  
  

Using well-documented claims and correct coding ensures you receive the appropriate payment amount for CPT 64490.

Prior Authorization and Coverage Limits

Many commercial payers now require prior authorization for facet joint procedures.

Documentation required for approval:

• Pain lasting more than 3 months
• Trial and failure of physical therapy or medications
• No evidence of alternative pain sources on imaging
• Pain scale score or functional limitation
• Details of previous diagnostic injections and relief percentage
  
  

Most payers limit 4 diagnostic and 4 therapeutic sessions per region within 12 months. Exceeding this limit without clear justification leads to denial.

Common Denials and How to Avoid Them

Here are the top reasons 64490 claims get denied and how to fix them.

How Preferred MB Can Help

Billing facet joint injections correctly requires detailed documentation knowledge of payer policies and smart modifier use. Many practices struggle to keep up. Partnering with a revenue cycle expert like Preferred MB helps eliminate errors prevent denials and improve cash flow through clean claim submission and payer compliance.

Final Thoughts

CPT 64490 may seem like just a billing code but it represents a highly regulated and frequently audited service. Mistakes can be costly. From correct modifier use to ICD 10 support to imaging guidance rules, every part of the claim matters.

Take the time to build a strong documentation process. Train your billing staff on payer policies. Track prior auth and session limits. And when in doubt, get help from billing experts.

Doing it right the first time means faster payment, fewer denials, and better outcomes for your patients and your practice.