ModifiedAmbetter NevadaPolicy CP.MP.165

Selective Nerve Root Blocks and Transforaminal Epidural Steroid Injections

Medical necessity criteria and coding guidance for selective nerve root blocks (SNRB) and transforaminal epidural steroid injections (TFESI) for treatment and diagnostic management of radicular pain; applies to providers and enrollees of Centene-affiliated health plans (Ambetter Nevada).

Policy Summary

PayerAmbetter Nevada

PolicySelective Nerve Root Blocks and Transforaminal Epidural Steroid Injections

Policy CodePolicy CP.MP.165

Change TypeMaterial updates to therapy durations, imaging and steroid guidance

Effective Date

Next Review Date

Key ActionObtain prior authorization when medical necessity criteria are required for TFESI/SNRB and document required conservative therapy and radicular localization.

SourceLink

POLICY UPDATE CHANGES

In I.B.4.a. and c. and II.B.5.a. and c. changed duration from six weeks to four weeks.

Added Table 1 to give examples of particulate and non-particulate steroids.

Updated Criteria II.D.3. from two months to three months regarding relief and functional improvement.

Removed anticoagulation therapy requirement in Criteria and added anticoagulation therapy as a note in Criteria.

Removed option for procedures without radiographic guidance; invasive pain procedures must be performed with radiographic guidance.

oneSNRB allowed per visit

oneTFESI allowed per visit

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Medical Necessity Criteria

Transforaminal Epidural Steroid Injection - Not Medically Necessary / Limits

Not covered when ANY of the following are met

TFESI Not Medically Necessary: 1) Continuation of injections beyond 12 months or more than 4 therapeutic injections at the same site; 2) TFESIs for indications other than specified acute or chronic radicular pain from disc herniation or spinal stenosis because effectiveness has not been established.>12 months or >4 injections/site/12 months

Continuation beyond limits is considered not medically necessary except on a case-by-case basis when definitive therapies cannot be provided or tolerated.

Selective Nerve Root Block - Not Medically Necessary

SNRB Not Medically Necessary: SNRBs are considered not medically necessary for any other indication because effectiveness has not been established.N/A

Explicit exclusion of other indications.

SNRBs and TFESIs are covered only for the specific acute and chronic radicular pain indications described in this policy. Procedures requested for any other clinical indications that are not listed in the coverage criteria are considered not medically necessary because effectiveness has not been established.

Coverage determinations under this clinical policy are subject to the terms, conditions, exclusions and limitations of the member’s coverage documents and applicable legal and regulatory requirements. For Medicaid members, when state Medicaid coverage provisions conflict with this clinical policy, state Medicaid coverage provisions take precedence.

Continuation of therapeutic injections beyond the policy limits is restricted. Specifically, continuation of injections beyond 12 months or more than 4 therapeutic injections at the same site within 12 months is considered not medically necessary because effectiveness and safety have not been established.

Procedure Codes and Coding References

Covered CPT Codes (informational)CPT

64479	Injection(s), anesthetic agent(s) and/or steroid, transforaminal epidural, with imaging guidance (fluoroscopy or CT), cervical or thoracic, single level.
64480	Injection(s), anesthetic agent(s) and/or steroid, transforaminal epidural, with imaging guidance (fluoroscopy or CT), cervical or thoracic, each additional level (List separately in addition to code for primary procedure).
64483	Injection(s), anesthetic agent(s) and/or steroid, transforaminal epidural, with imaging guidance (fluoroscopy or CT), lumbar or sacral, single level.
64484	Injection(s), anesthetic agent(s) and/or steroid, transforaminal epidural, with imaging guidance (fluoroscopy or CT), lumbar or sacral, each additional level (List separately in addition to code for primary procedure).

References to coding resources and LCDmixed

No codes listed

Therapeutic injection frequency — Less than 4 injections at same site within 12 months

Frequency limitLess than 4 therapeutic injections at the same site within any 12-month period

Assessment windowCount injections per anatomical site over a rolling 12-month period

Not medically necessary if exceededContinuation beyond 12 months or more than 4 therapeutic injections at same site is considered not medically necessary

Exception handlingCase-by-case consideration when definitive therapies cannot be tolerated or provided

Authorization, Documentation, and Responsibilities

Prior Authorization

Prior Authorization Required

Prior authorization is required for transforaminal epidural steroid injections (TFESI) and selective nerve root blocks (SNRB) when medical necessity criteria must be met for the following CPT codes: 64479, 64480, 64483, 64484. Procedures must be performed per policy (single procedure per visit, radiographic guidance, appropriate steroid selection for cervical TFESI).

CPT 64479, 64480, 64483, 64484

Note

Plan-Determined Prior Authorization and Medicare/LCD Consistency

This clinical policy is effective as determined by the Health Plan and may be updated, amended, or withdrawn at any time. For Medicare members, providers must review and follow applicable NCDs, LCDs, and Medicare Coverage Articles to ensure consistency with Medicare coverage determinations. State Medicaid provisions take precedence over this policy where applicable.

Health Plan may require adherence to applicable NCDs/LCDs for Medicare members
State Medicaid rules override when in conflict

Noninvasive Therapy Prerequisites

Radiographic Guidance and Imaging

Billing Rule

Use real-time imaging (fluoroscopy or CT) for TFESI and radiographic guidance for SNRB/TFESI

Procedures must be performed with real-time radiographic guidance (fluoroscopy or CT); the policy requires radiographic guidance for TFESI and implies radiographic guidance for SNRB.

Real-time imaging (fluoroscopy or CT) required for TFESI
Radiographic guidance is required for invasive pain procedures performed by a physician

Note

Refer to ASIPP, CMS LCD and guideline references for imaging/technique details

The policy cites ASIPP, CMS LCD and other guideline and evidence sources that commonly address imaging and technique considerations; review these references when technique or imaging questions arise.

References include ASIPP guidelines and CMS Local Coverage Determination L39240

Limits on Number and Timing of Injections

TFESI therapeutic injections — Less than 4 injections at the same site within 12 months

TFESI frequency limitLess than 4 therapeutic injections at the same site within any 12-month period

Subsequent TFESI requirementFor subsequent TFESI after prior improvement: ≥50% relief and functional improvement for at least three months since last injection

Timing after prior TFESIAt least two weeks must have passed since the first TFESI for second (no-improvement) requests

Cervical TFESI special requirementIf cervical TFESI is requested, non-particulate steroid must be used and procedure must be conducted with real-time imaging (fluoroscopy)

Key Terms

SNRB — Selective Nerve Root Block definition and purpose

DefinitionSelective Nerve Root Block (SNRB): injection of a small amount of local anesthetic adjacent to a spinal nerve root, most often used to diagnose the source of radicular pain

Therapeutic useWhen used therapeutically, a steroid may be added (often referred to as selective transforaminal epidural steroid injection)

Primary purposePrimarily diagnostic localization of the symptomatic nerve root

TFESI — Transforaminal Epidural Steroid Injection definition and purpose

DefinitionTransforaminal Epidural Steroid Injection (TFESI): injection of local anesthetic and/or corticosteroid into the intervertebral foramen to target nerve roots where injectate spreads to affect multiple nerves

Imaging requirement

Clinical Background

Selective nerve root blocks (SNRBs) and transforaminal epidural steroid injections (TFESIs) are image-guided epidural procedures used to manage radicular pain. SNRBs typically involve injection of local anesthetic adjacent to a specific spinal nerve root and are commonly used for diagnostic localization (therapeutic SNRB may include steroid). TFESIs deliver local anesthetic and/or corticosteroid into the intervertebral foramen to target affected nerve roots and may be used for short-term pain relief and to improve function.

Services Considered Not Medically Necessary

SNRBs and TFESIs requested for indications other than the specified acute or chronic radicular pain conditions (for example, indications not described in the policy criteria such as non‑radicular low back pain or other unlisted uses) are not covered because effectiveness for those indications has not been established.

Policy Summary

PayerAmbetter Nevada

PolicySelective Nerve Root Blocks and Transforaminal Epidural Steroid Injections

Policy CodePolicy CP.MP.165

Change TypeMaterial updates to therapy durations, imaging and steroid guidance

Effective Date

Next Review Date

Key ActionObtain prior authorization when medical necessity criteria are required for TFESI/SNRB and document required conservative therapy and radicular localization.

SourceLink

On This Page

Denial Risk

Denial Triggers

Requests may be denied when documentation is incomplete or when frequency and conservative therapy requirements are not met. Examples include: exceeding allowed number of injections at a site within 12 months, requests for continuation beyond 12 months or more than four therapeutic injections without case-by-case justification, lack of required conservative therapy trials, or missing evidence of prior benefit for continuation injections.

More than 4 therapeutic injections at the same site within 12 months is a denial trigger
Continuation beyond 12 months or >4 injections generally considered not medically necessary
Requests lacking required conservative therapy trials (see documentation block) may be denied
Insufficient documentation of prior benefit (for continuation requests) may be denied

Note

Coverage and Denial Context

Coverage determinations are subject to the member's benefit plan, eligibility, exclusions, and limitations. This clinical policy is a guide and does not guarantee payment. Providers remain responsible for exercising professional medical judgment and for submitting complete, accurate claims and documentation. When benefit plan language conflicts with this clinical policy, the terms of the coverage documents govern.

Decisions are subject to member contract, state Medicaid rules (when applicable), and plan exclusions/limitations
This policy does not replace provider clinical judgment and is not a guarantee of coverage

Documentation Required

Required Clinical Documentation

Required clinical documentation must demonstrate the diagnosis and medical necessity for the requested SNRB or TFESI. Documentation should include: radicular pain localized to a specific nerve root level; description of how pain interferes with activities of daily living; duration of symptoms (acute <3 months or chronic ≥3 months); results of relevant imaging and, when applicable, electrodiagnostic testing (EMG/nerve conduction studies); and evidence of completed conservative therapies with durations. For continuation requests, documentation must show prior meaningful benefit (≥50% pain relief and functional improvement lasting at least three months) and timing relative to prior injections.

Evidence localizing radicular pain to a defined nerve root level
Imaging confirming disc herniation or spinal stenosis when applicable
Electrodiagnostic studies when diagnosis remains uncertain
Conservative therapy trials: ≥4 weeks chiropractic/physical therapy/home exercise, ≥3 weeks NSAID (or documentation of contraindication/intolerance), ≥4 weeks activity modification
For continuation TFESI: documentation of ≥50% relief and functional improvement for ≥3 months since last injection
Timing limits: at least 2 weeks between injections when required; less than 4 injections at same site within 12 months; less than 12 months since initial injection at the level requested