ModifiedUnitedHealthcarePolicy CS363TN.D

Interspinous Fusion and Decompression Devices (for Tennessee Only)

This policy governs coverage of interspinous fixation (fusion) devices and interspinous decompression/interlaminar stabilization devices for Medicaid and CoverKids members in Tennessee.

Policy Summary

PayerUnitedHealthcare

PolicyInterspinous Fusion and Decompression Devices (for Tennessee Only)

Policy CodePolicy CS363TN.D

Change TypeMaterial revisions and documentation additions

Effective DateJan 1, 2026

Next Review Date

Key ActionObtain and submit complete medical records and prior authorization documentation demonstrating that interspinous fixation is used adjunctive to interbody fusion and that clinical criteria are met.

SourceLink

POLICY UPDATE CHANGES

Medical records documentation requirements were added to indicate that documentation may be required to assess whether the member meets clinical criteria and that documentation must fully support medical necessity.

Clinical evidence and references sections were updated to reflect the most current information, including recent HTAs and systematic reviews.

Definitions for Arthrodesis, Interlaminar Lumbar Instrumented Fusion (ILIF), Interlaminar Stabilization Device, and Neurogenic Claudication were updated.

coveredInterspinous fixation stance

not coveredDecompression/ILD without fusion

L1-S1Allowed spinal levels

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grade 1Max spondylolisthesis

single levelUse limited to

addedDocumentation requirement

Coverage Criteria for Interspinous Devices

Covered: Interspinous fixation devices (adjunct to fusion)

Interspinous fixation (fusion) devices are considered proven and medically necessary when ALL of the following criteria are met:

Interspinous fixation coverage criteria: Performed according to FDA labeled indications, contraindications, warnings, and precautions.

Interspinous fixation coverage criteria: Back pain of discogenic origin with degeneration of the disc confirmed by history and radiographic studies.

Interspinous fixation coverage criteria: No more than grade 1 spondylolisthesis.

Interspinous fixation coverage criteria: Used with an interbody cage as an adjunct to fusion at a single lumbar level (L1–S1).

Not medically necessary: Interspinous decompression/ILD without fusion

Interspinous decompression and interlaminar stabilization systems (without fusion):

Decompression/Interlaminar devices stance: Considered unproven and not medically necessary for the treatment of spine pain or lumbar spinal stenosis due to insufficient evidence of efficacy.

Interspinous fusion devices (with fusion) - NASS-based criteria

NASS 2025 guidance for interspinous fusion devices indicates they may be considered when ALL of the following contextual conditions are met:

Primary situational requirements: Device affixes to the spinous processes and is used as an adjunct in the context of lumbar fusion procedures (e.g., for stenosis, disc herniation, or synovial facet cyst excision), and is utilized with robust open laminar and/or facet decortication and fusion and/or robust autograft inter- and extra-spinous process decortication and/or interbody fusion of the same motion segment.

From NASS 2025 coverage recommendations

Contraindications (must not be present): Spondylolisthesis greater than Grade I; bilateral isthmic spondylolysis; significant dynamic instability (e.g., on flexion-extension views); scoliosis or coronal/rotatory instability; indication for fusion at more than one lumbar level; generally not indicated at L5–S1 unless anatomy is favorable; complete resection of the facet (unless accompanied by an interbody fusion); and other scenarios where interspinous fixation without open decortication and fusion is unsupported.

Enumerated exclusions from NASS 2025

Interspinous distraction devices without fusion (used instead of decompression) - NASS-based criteria

NASS 2025 guidance for static interspinous distraction devices (used instead of direct decompression) — Covered when ALL of the following qualifying criteria are met:

Clinical symptoms: Clinically symptomatic degenerative lumbar stenosis associated with neurogenic claudication that is relieved by lumbar flexion.

NASS 2025

Functional ability: Able to sit for at least 50 minutes without pain and able to walk at least 50 feet.Sitting ≥ 50 minutes; walking ≥ 50 feet

NASS 2025 functional criteria

Imaging severity: Mild to moderate stenosis on CT or MRI defined as a 25–50% reduction in lateral/central foraminal diameter compared to adjacent levels.25–50% reduction

Interspinous fixation (fusion) devices are considered proven and medically necessary only when implanted in accordance with FDA-labeled indications, contraindications, warnings, and precautions and when all specified clinical criteria are met. Key qualifying criteria include documented discogenic back pain with radiographic confirmation of disc degeneration, no more than Grade I spondylolisthesis, and use of the interspinous fixation device as an adjunct to an interbody fusion with an interbody cage at a single lumbar level (L1–S1). Use of interspinous fixation devices off‑label as standalone distraction/decompression devices without interbody fusion is not supported by this policy.

The North American Spine Society (NASS) 2025 guidance lists specific contraindications and situational limits for distraction/interspinous devices. Contraindications and exclusions include: spondylolisthesis greater than Grade I, bilateral isthmic spondylolysis, significant dynamic instability (for example, on flexion‑extension views), scoliosis or coronal/rotatory instability, and when fusion is indicated at more than one lumbar level. NASS additionally notes devices are generally not indicated at L5–S1 due to S1 spinous anatomy unless anatomic conditions are favorable, and other exclusions include complete facet resection (unless accompanied by interbody fusion) and scenarios outlined for static devices in which patient anatomy, prior surgery, or comorbidities fall outside the qualifying parameters.

Per NASS 2025, interspinous fixation devices should not be used without performing an open decortication and fusion of the posterior bony elements or without performing an interbody fusion; these devices are intended to be used as an adjunct to robust decortication and fusion techniques rather than as standalone implants.

Interspinous decompression devices (spacers) and interlaminar stabilization systems that are implanted without fusion — either as decompression alternatives or as dynamic stabilization alone — are considered unproven and not medically necessary for the treatment of spine pain or lumbar spinal stenosis because the available evidence is insufficient to establish long‑term safety and effectiveness.

The overall body of evidence for interspinous spacer and interlaminar stabilization devices is of low to insufficient quality. Available studies are generally small, retrospective, or at risk of bias, and long‑term comparative randomized trials versus standard decompression are lacking. Systematic reviews and technology assessments report uncertainty about sustained clinical benefit and note higher reoperation rates for interspinous implants in some analyses, so these devices are not supported as equivalent to standard decompression in many contexts.

Procedure and Billing Codes

Applicable Codes (interbody device)CPT

22853

Insertion of interbody biomechanical device(s) (e.g., synthetic cage, mesh) with integral anterior instrumentation for device anchoring (e.g., screws, flanges), when performed, to intervertebral disc space in conjunction with interbody arthrodesis, each interspace (List separately in addition to code for primary procedure)

Applicable Codes (interspinous/interlaminar devices)CPT

22854	Insertion of intervertebral biomechanical device(s) (e.g., synthetic cage, mesh) with integral anterior instrumentation for device anchoring (e.g., screws, flanges), when performed, to vertebral corpectomy(ies) (vertebral body resection, partial or complete) defect, in conjunction with interbody arthrodesis, each contiguous defect (List separately in addition to code for primary procedure).
22859	Insertion of intervertebral biomechanical device(s) (e.g., synthetic cage, mesh, methylmethacrylate) to intervertebral disc space or vertebral body defect without interbody arthrodesis, each contiguous defect (List separately in addition to code for primary procedure).
22867	Insertion of interlaminar/interspinous process stabilization/distraction device, without fusion, including image guidance when performed, with open decompression, lumbar; single level.
22868	Insertion of interlaminar/interspinous process stabilization/distraction device, without fusion, including image guidance when performed, with open decompression, lumbar; second level (List separately in addition to code for primary procedure).
22869	Insertion of interlaminar/interspinous process stabilization/distraction device, without open decompression or fusion, including image guidance when performed, lumbar; single level.
22870	Insertion of interlaminar/interspinous process stabilization/distraction device, without open decompression or fusion, including image guidance when performed, lumbar; second level (List separately in addition to code for primary procedure).
22899	Unlisted procedure, spine [when specified as insertion of a non-pedicle interspinous process fixation device]

Conservative treatment duration — failure of 6 months nonoperative treatment

Conservative treatment durationFailure of 6 months of nonoperative treatment is required before considering static interspinous distraction devices per NASS 2025 guidance.

ContextApplies to static interspinous distraction devices used instead of direct decompression (per NASS 2025).

Documentation implicationMedical records must document the 6-month nonoperative treatment and its failure to support prior authorization and medical necessity review.

Walking/sitting functional criteria (NASS)

Sitting thresholdAble to sit for at least 50 minutes without pain (NASS 2025 functional criterion).

Walking threshold

Provider Requirements, Prior Authorization, and Documentation

Prior Authorization

Procedure Coding and Authorization

Prior authorization is recommended for interspinous fixation procedures. Submit applicable procedure codes and clinical records to support medical necessity. UnitedHealthcare may use third-party criteria (e.g., InterQual) in prior authorization reviews.

Affecting codes: 22853, 22854, 22859, 22867, 22868, 22869, 22870, 22899
Authorization recommended when interspinous fixation is performed as adjunct to interbody fusion

Denial Risk

Denial Risk for Decompression Devices Without Fusion

Requests for interspinous decompression/interlaminar stabilization devices without documented fusion (or without an appropriate adjunctive interbody fusion at a single lumbar level) are at risk of denial because these uses are considered unproven or not medically necessary.

Denial risk for codes: 22867-22870, 22899 when used without fusion

Background and Evidence Summary

Lumbar spinal stenosis is a pathologic narrowing of the lumbar spinal canal or neural foramina that can compress neural structures and produce neurogenic claudication, typically manifesting as leg pain or weakness worsened by standing or walking and relieved by spinal flexion. Interspinous devices were developed to provide indirect decompression or posterior stabilization as less invasive alternatives to laminectomy and fusion. Interspinous fixation devices are intended to augment fusion procedures by affixing to the spinous processes to promote stabilization and fusion, while interspinous spacers or interlaminar stabilization devices aim to reduce extension and relieve neurogenic claudication without formal fusion. Clinical evidence supports the use of interspinous fixation only when used adjunctively with interbody fusion per FDA labeling and the policy criteria; evidence for decompression‑only spacers and interlaminar stabilization without fusion remains limited and inconclusive.

For context, multiple systematic reviews, HTAs, and device‑specific assessments conclude the evidence base for interspinous spacers and related devices is limited by small studies, risk of bias, and lack of independent long‑term randomized comparisons. These sources consistently rate the quality of evidence as low or insufficient, highlight inconsistent guideline recommendations, and report concerns such as higher reoperation rates and uncertain long‑term benefit compared with standard decompression.

Definitions

Interspinous Fixation Devices — definition and intended use

DefinitionInterspinous fixation devices are implants attached to the spinous processes to achieve stabilization and promote fusion in patients with degenerative disc disease.

Intended useUsed as an adjunct to interbody fusion procedures to stabilize the posterior elements and support arthrodesis, typically at a single lumbar level (L1–S1) per policy coverage criteria.

Not for decompression alonePolicy notes these fixation devices should not be used off-label as decompression (distraction) devices without performing open decortication and fusion.

Interspinous Process Decompression (IPD) — definition of spacer decompression

DefinitionInterspinous Process Decompression (IPD) is a minimally invasive procedure that implants a spacer between affected spinous processes to distract the neural foramen and decompress nerves; spacers are implanted midline between adjacent lamina and spinous processes.

Policy Summary

PayerUnitedHealthcare

PolicyInterspinous Fusion and Decompression Devices (for Tennessee Only)

Policy CodePolicy CS363TN.D

Change TypeMaterial revisions and documentation additions

Effective DateJan 1, 2026

Next Review Date

SourceLink

On This Page

Imaging threshold per NASS 2025

Conservative therapy failure: Failure of 6 months of nonoperative treatment.6 months

NASS 2025 requirement

Anatomic and comorbidity limits: No more than 25° degenerative scoliosis; no more than Grade I degenerative spondylolisthesis; open surgery (e.g., laminectomy) is not a medically safe option because of comorbidities, when applicable.

NASS 2025

Able to walk at least 50 feet (NASS 2025 functional criterion).

PurposeFunctional thresholds are part of the clinical qualifying criteria for static interspinous distraction devices used instead of direct decompression.

Imaging stenosis severity — mild to moderate stenosis definition (25-50% reduction)

Imaging severity definitionMild to moderate stenosis defined on CT or MRI as a 25–50% reduction in lateral/central foraminal diameter compared to adjacent levels.

ModalityAssessment specified for advanced imaging (CT or MRI).

ContextThis imaging threshold is part of NASS 2025 qualifying criteria for static interspinous distraction devices used instead of decompression.

Scoliosis limit — maximum 25° degenerative scoliosis

Maximum Cobb/degenerative scoliosisNo more than 25° of degenerative scoliosis is allowed for consideration of static interspinous distraction devices.

Contraindication noteDegenerative scoliosis greater than 25° is explicitly listed as not indicated by NASS 2025.

ApplicationPart of anatomic and comorbidity limits in the NASS 2025 criteria for static interspinous devices used instead of decompression.

Spondylolisthesis limit — no more than Grade I degenerative spondylolisthesis

Maximum spondylolisthesisNo more than Grade I degenerative spondylolisthesis is allowed for static interspinous distraction devices.

ContraindicationDegenerative spondylolisthesis of Grade II or higher is explicitly not indicated by NASS 2025.

Relation to fusion devicesInterspinous fixation used as adjunct to fusion also requires no more than grade 1 spondylolisthesis per policy criteria.

BMI exclusion threshold — BMI >= 40 exclusion

BMI exclusion thresholdBMI >= 40 is listed as a condition in which static interspinous distraction devices are not indicated (NASS 2025).

Clinical implicationHigh BMI is an explicit exclusion in the NASS 2025 scenarios for considering interspinous distraction devices instead of decompression.

DocumentationPatient BMI should be documented in the medical record to support coverage determinations and prior authorization reviews.

Interspinous fixation covered only as adjunct to interbody fusion at a single lumbar level (L1-S1)

Documentation Required

Documentation-Related Denial Risk

Medical records must fully support the medical necessity for the requested service. Inadequate, illegible, or incomplete documentation may lead to denial of the request.

Documentation must include relevant medical history, physical exam, and results of pertinent diagnostic tests or procedures
Records must be legible, maintained in the patient's medical record, and available upon request
Insufficient documentation may result in denial

Documentation Required

Required Documentation

The patient's medical record must contain documentation that fully supports medical necessity, including history, physical examination findings, and diagnostic test results. Documentation may be requested to assess whether clinical criteria are met and does not guarantee coverage.

Include: relevant history, focused physical exam, imaging (e.g., MRI/CT) and other pertinent tests
Ensure records are legible and readily available for review
Submission of records may be required for prior authorization or claims review

Prior Authorization

Conservative Treatment Documentation

Evidence of failure of conservative (nonoperative) treatment is required when applicable. For interspinous distraction devices considered for degenerative lumbar stenosis, documentation of at least 6 months of nonoperative treatment is expected.

Document duration and type of conservative treatments tried (e.g., physical therapy, medications, injections) — failure of 6 months is expected for certain indications
Include functional status (walking tolerance), symptom behavior (relief with flexion), and imaging correlates of mild to moderate stenosis when applicable

Typical useIPD is described as dynamic stabilization and is typically used without fusion; static devices provide indirect decompression and dynamic devices are labeled for use with direct decompression.

Coverage stanceInterspinous decompression devices used without fusion are generally considered unproven and not medically necessary per policy unless specific NASS 2025 static-device criteria are met.

Interlaminar Stabilization Device — definition and purpose

DefinitionInterlaminar Stabilization Device: an implantable interspinous process device intended to provide symptomatic relief of claudicatory lumbar spinal stenosis by reducing lumbar extension while preserving flexion, axial rotation, and lateral bending; typically implanted after decompression.

Device descriptionExample description includes a U-shaped titanium implant inserted horizontally between adjacent spinous processes with wings crimped over bone to hold the implant in place.

Usage notePolicy updated definition clarifies placement between spinous processes to provide stabilization following decompression and that these devices are distinct from interspinous fixation used as fusion adjuncts.

Interlaminar Stabilization Device (alternate/updated def)

Updated definitionInterlaminar Stabilization Device: device placed between spinous processes to provide stabilization following decompression (definition updated in policy).

Clinical roleIntended to provide symptomatic relief for claudicatory lumbar spinal stenosis and to limit extension while preserving other ranges of motion.

DistinctionPolicy distinguishes interlaminar stabilization devices (implanted after decompression) from interspinous fixation devices used to promote fusion.

Interlaminar Lumbar Instrumented Fusion (ILIF) — updated definition

DefinitionInterlaminar Lumbar Instrumented Fusion (ILIF): a procedure where an opening is created through the ligaments to access spinous processes, decompression is performed, bone graft (allograft or autograft) is placed between spinous processes and on remaining lamina, and an implant is inserted to stabilize the spine until fusion occurs.

Procedure elementsIncludes removal of compressive bone/ligament/disc tissue, placement of graft material in the disc space and between spinous processes, and insertion of an implant to secure spinous processes during fusion.

Policy noteDefinition updated in policy history to clarify interlaminar instrumentation and fusion technique.

Neurogenic Claudication — symptomatic definition (leg pain/weakness relieved by flexion)

Symptomatic definitionNeurogenic claudication: leg pain or weakness related to lumbar stenosis that is exacerbated by standing or walking and relieved by lumbar flexion or change in position.

Clinical differentiationShould be differentiated from vascular claudication when evaluating patients for interspinous devices.

Relevance to device criteriaRelief of neurogenic claudication by flexion is a required clinical symptom for consideration of static interspinous distraction devices per NASS 2025.

Arthrodesis — updated definition for fusion of vertebral segments

DefinitionArthrodesis: a surgical procedure to eliminate motion in a joint by providing a bony fusion; used to relieve pain, provide stability, correct postural deformity from neurologic deficit, and halt advancing disease.

Context in spine surgeryArthrodesis is the intended biologic outcome of fusion procedures where implants (including interspinous fixation devices used adjunctively) stabilize the posterior elements until fusion occurs.

Policy updateDefinition of arthrodesis was updated in the policy revision effective 01/01/2026.