Archived Policies - Surgery

Interspinous Fixation (Fusion) Devices


Effective Date:09-01-2016

End Date:01-31-2017


Interspinous fixation (fusion) devices, including but not limited to Coflex-F®, are considered experimental, investigational and/or unproven for any indication, including but not limited to use:

In combination with interbody fusion, or

Alone for decompression in patients with spinal stenosis.

NOTE: The Coflex Interlaminar Stabilization Device, referred to in SUR712.029 (Interspinous Distraction (Spacers) and Interlaminar Stabilization Device), is different from the Coflex-F® device addressed in this policy.


Contemporary models of interspinous fixation devices have evolved from spinous process wiring with bone blocks and early device designs (e.g., Wilson plate, Meurig-Williams system, Daab plate). The newer devices range from paired plates with teeth to U-shaped devices with wings that are attached to the spinous process. They are intended to be an alternative to pedicle screw and rod constructs to aid in the stabilization of the spine with interbody fusion. Interspinous fixation devices are placed under direct visualization, while screw and rod systems may be placed either under direct visualization or percutaneously. Use of an interspinous fixation device in combination with a unilateral pedicle screw system has also been proposed. Interspinous fixation devices are not intended for stand-alone use.

Interspinous fixation (fusion) devices contrast with interspinous distraction devices (spacers), which are used alone for decompression and are typically not fixed to the spinous process. In addition, whereas interspinous distraction devices may use dynamic stabilization, interspinous fixation devices are rigid. However, the fixation devices might also be used to distract the spinous processes and decrease lordosis. Thus, the fixation devices might be used off-label without interbody fusion as decompression (distraction) devices in patients with spinal stenosis. If fixation devices are used alone as a spacer, there is a risk of spinous process fracture.

For use in combination with fusion, it is proposed that interspinous fixation systems are less invasive and present fewer risks than pedicle or facet screws. However, while biomechanical studies indicate that interspinous fixation devices may be similar to pedicle screw-rod constructs in limiting the range of flexion-extension, they may be less effective than bilateral pedicle screw-rod fixation for limiting axial rotation and lateral bending. (1) There is a potential for a negative impact on the interbody cage and bone graft due to focal kyphosis resulting from the interspinous device. There is also a potential for spinous process fracture. Given these uncertainties, studies are needed that compare health outcomes between interspinous fixation devices and pedicle screw-rod fixation.


The following interspinous fixation devices have received clearance to market by the U.S. Food and Drug Administration (FDA). This may not be an exhaustive list.

Affix™ (NuVasive)

Aileron™ (Life Spine)

Aspen™ (Lanx, acquired by BioMet)

Axle™ (X-Spine)

BacFuse® (Pioneer Surgical)

BridgePoint™ (Alphatec)

coflex-F® (Paradigm Spine)

Inspan™ (Spine Frontier)

Interbridge Interspinous Posterior Fixation System (LDR Spine)

PrimaLOK™ (OsteoMed)

Octave™ (Life Spine)

Spire™ (Medtronic)

SP-Fix™ (Globus)

Zip Mis Interspinous Fusion System

Interspinous fixation devices are intended to be used as an adjunct to interbody fusion. For example, the indication for use of the coflex-F implant

“is a posterior, nonpedicle supplemental fixation device intended for use with an interbody cage as an adjunct to fusion at a single level in the lumbar spine (L1-S1). It is intended for attachment to the spinous processes for the purpose of achieving stabilization to promote fusion in patients with degenerative disc disease – defined as back pain of discogenic origin with degeneration of the disc confirmed by history and radiographic studies – with up to Grade 1 spondylolisthesis.”

Use of an interspinous fixation device for a stand-alone procedure would be considered off-label.

FDA Product code: PEK.


Several studies were identified that evaluated the biomechanics of interspinous fixation devices, but no English language publications were found that evaluated clinical outcomes with use of these devices when used in combination with fusion.

Use of the Aspen interspinous fixation device as a stand-alone interspinous spacer was reported in a prospective series of 6 cases (an additional 32 patients received the X-stop interspinous distraction device). (2) The study population consisted of consecutive patients with a primary diagnosis of lumbar spinal stenosis with pain that was relieved by sitting or lumbar flexion. Of the 6 patients implanted with the Aspen device, 2 (33%) had spinous process fractures observable on computed tomography. Of the entire group of 38 patients, 55% of those with spondylolisthesis (n=20) had a fracture within 6 months of surgery. None of the 18 patients without spondylolisthesis experienced a fracture. In 2013, use of an interspinous fusion plate was reported in a series of 4 patients in conjunction with surgery for recurrent lumbar disc herniation. (3)

Ongoing and Unpublished Clinical Trials

An online search of in July 2014 found the following ongoing trials:

NCT01016314 is an industry-sponsored phase 4, multicenter, randomized, open-label comparison of the Aspen Spinous Process System versus pedicle screw fixation in patients undergoing lumbar fusion. The study has an estimated enrollment of 156 patients with completion expected December 2015.

NCT01019057 is an industry-sponsored study of interlaminar lumbar instrumented fusion (ILIF™) in 77 patients undergoing posterior decompression followed with an allograft spacer, spinous process fixation plate (Affix™), and a biologic. The study was completed in June 2014.

Summary of Evidence

Interspinous fixation (fusion) devices are being developed to aid in the stabilization of the spine. They are being evaluated as alternatives to pedicle screw and rod constructs in combination with interbody fusion. Interspinous fixation devices are also being evaluated for stand-alone use in patients with spinal stenosis. There is a lack of evidence on the efficacy of interspinous fixation devices, both for use in combination with interbody fusion and for use as a stand-alone procedure. Randomized controlled trials are needed that evaluate health outcomes following use of interspinous fixation (fusion) devices in comparison with the established standard of pedicle screw-rod fixation. Clinical trials are also needed to evaluate these devices when used alone for decompression. Because of the lack of evidence, interspinous fixation devices are considered experimental, investigational and/or unproven.


Practice Guidelines and Position Statements

The North American Spine Society (NASS) issued a coverage position on the use of interspinous devices with lumbar fusion. (4) NASS recommends that interspinous fixation with fusion for stabilization is currently not indicated as an alternative to pedicle screw fixation with lumbar fusion procedures.


Each benefit plan, summary plan description or contract defines which services are covered, which services are excluded, and which services are subject to dollar caps or other limitations, conditions or exclusions. Members and their providers have the responsibility for consulting the member's benefit plan, summary plan description or contract to determine if there are any exclusions or other benefit limitations applicable to this service or supply. If there is a discrepancy between a Medical Policy and a member's benefit plan, summary plan description or contract, the benefit plan, summary plan description or contract will govern.


There are no specific CPT codes for insertion of these devices. The following add on codes might be used: 22840 and 22851.


Disclaimer for coding information on Medical Policies

Procedure and diagnosis codes on Medical Policy documents are included only as a general reference tool for each policy. They may not be all-inclusive.

The presence or absence of procedure, service, supply, device or diagnosis codes in a Medical Policy document has no relevance for determination of benefit coverage for members or reimbursement for providers. Only the written coverage position in a medical policy should be used for such determinations.

Benefit coverage determinations based on written Medical Policy coverage positions must include review of the member’s benefit contract or Summary Plan Description (SPD) for defined coverage vs. non-coverage, benefit exclusions, and benefit limitations such as dollar or duration caps.


The following codes may be applicable to this Medical policy and may not be all inclusive.

CPT Codes

22853, 22854, 22859



ICD-9 Diagnosis Codes

Refer to the ICD-9-CM manual

ICD-9 Procedure Codes

Refer to the ICD-9-CM manual

ICD-10 Diagnosis Codes

Refer to the ICD-10-CM manual

ICD-10 Procedure Codes

Refer to the ICD-10-CM manual

Medicare Coverage:

The information contained in this section is for informational purposes only. HCSC makes no representation as to the accuracy of this information. It is not to be used for claims adjudication for HCSC Plans.

The Centers for Medicare and Medicaid Services (CMS) does not have a national Medicare coverage position. Coverage may be subject to local carrier discretion.

A national coverage position for Medicare may have been developed since this medical policy document was written. See Medicare's National Coverage at <>.


1. Wu JC, Mummaneni PV. Using lumbar interspinous anchor with transforaminal lumbar interbody fixation. World Neurosurg. May 2010; 73(5):471-472. PMID 20920928

2. Kim DH, Shanti N, Tantorski ME, et al. Association between degenerative spondylolisthesis and spinous process fracture after interspinous process spacer surgery. Spine J. Jun 2012; 12(6):466-472. PMID 22622239

3. Oppenheim JS, Mills J. Recurrent lumbar disc herniation treated with interspinous fusion and instrumentation: a case series. Surg Technol Int. Sep 2013; 23:269-272. PMID 23686800

4. North American Spine Society (NASS). NASS coverage policy recommendations: Interspinous fixation with fusion. Available at <> (accessed 2014 July).

5. Interspinous Fixation (Fusion) Devices. Chicago, Illinois: Blue Cross Blue Shield Association Medical Policy Reference Manual (2014 September) Surgery 7.01.138.

Policy History:

Date Reason
9/1/2016 Reviewed. No changes.
2/1/2016 New medical Document. Interspinous fixation (fusion) devices are considered experimental, investigational and/or unproven for any indication, including but not limited to use: In combination with interbody fusion, or alone for decompression in patients with spinal stenosis.

Archived Document(s):

Title:Effective Date:End Date:
Interspinous Fixation (Fusion) Devices11-15-201807-31-2019
Interspinous Fixation (Fusion) Devices09-01-201711-14-2018
Interspinous Fixation (Fusion) Devices02-01-201708-31-2017
Interspinous Fixation (Fusion) Devices09-01-201601-31-2017
Interspinous Fixation (Fusion) Devices02-01-201608-31-2016
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