Axial or presacral lumbar interbody fusion is a minimally invasive technique designed to provide anterior access to the L4-S1 disc spaces for interbody fusion while minimizing damage to muscular, ligamentous, neural, and vascular structures. It is performed under fluoroscopic guidance using specialized instrumentation.

Investigational and Not Medically Necessary:

Axial or presacral lumbar interbody fusion is considered investigational and not medically necessary.

The AxiaLIF^® and the AxiaLIF^® II or 2-Level Systems (TranS1^®, Inc.) provide the specialized instruments to perform lumbar fusion using the axial approach.  The AxiaLIF system was cleared for marketing through the U.S. Food and Drug Administration (FDA) 510(k) process.  The Premarket Notification summaries indicate that the procedures are intended to provide anterior stabilization of the spinal segments as an adjunct to spinal fusion and for assisting in the treatment of degeneration of the lumbar disc, performing lumbar discectomy, or for assistance in the performance of interbody fusion.  The AxiaLIF  systems are indicated for individuals requiring fusion to treat pseudoarthrosis, unsuccessful previous fusion, spinal stenosis, spondylolisthesis (Grade 1), or degenerative disc disease as defined as back pain of discogenic origin with degeneration of the disc confirmed by history and radiographic studies. They are not intended to treat severe scoliosis, severe spondylolisthesis (Grades 2, 3 and 4), tumor, or trauma.  AxiaLIF is not meant to be used in those with vertebral compression fractures or any other condition where the mechanical integrity of the vertebral body is compromised. Their usage is limited to anterior supplemental fixation of the lumbar spine at L5-S1 or L4-S1 in conjunction with legally marketed facet or pedicle screw systems.

The published literature reporting outcomes for axial lumbar interbody fusion is limited to a technical report and two retrospective case series with individuals who received AxiaLIF at L5-S1. Aryan and colleagues (2008) reported on a series of 35 individuals with average follow-up of 17.5 months. These individuals had pain secondary to lumbar degenerative disc disease, degenerative scoliosis, or lytic spondylolisthesis. In 21 of the individuals, the AxiaLIF procedure was followed by percutaneous pedicle/screw-rod fixation, 2 had extreme lateral interbody fusion combined with posterior instrumentation, and 10 had a stand alone procedure. Two individuals had AxiaLIF as part of a larger construct after unfavorable anatomy prevented access to the L5-S1 disc space during open lumbar fusion. Thirty-two individuals had radiographic evidence of stable cage placement and fusion at last follow-up.

In another study, Patil and colleagues (2010) reported a retrospective review of 50 individuals treated with AxiaLIF. Four participants (8%) underwent 2-level AxiaLIF and 16 participants (32%) underwent a combination of AxiaLIF with another procedure for an additional level of fusion. There were 3 reoperations due to pseudoarthrosis (n=2) and rectal injury (n=1). Other complications included superficial infection (n=5), hematoma (n=2), and irritation of a nerve root by a screw (n=1). At 12- to 24-month follow-up VAS scores had decreased from 8.1 to 3.6 (n = 48). At an average 12-month follow-up, 47 of 49 participants (96%) with postoperative radiographs achieved solid fusion. There were no significant differences between pre- and postoperative disk space height and lumbar lordosis angle. Although the authors of these 2 studies reported that AxiaLIF provides a minimally invasive approach for discectomy and interbody fusion and may be of value in those with contraindications to the traditional open anterior approach, further well designed randomized comparative clinical trials are necessary to demonstrate the safety and efficacy of this surgical procedure.

Shen and colleagues (2007) reviewed minimally invasive techniques for lumbar interbody fusion. They noted that experience with the technique is limited and complication rates are unknown. Complications may include perforation of the bowel and injury to blood vessels and/or nerves as well as infection. They also pointed out the increased need for fluoroscopy and the inability of the surgeon to assess intracanal pathology or visualize the surgical field directly.

The AxiaLIF  and AxiaLIF II Level Systems consist of techniques and surgical instruments for creating a pre-sacral access route to perform percutaneous fusion of the L5-S1 or L4-S1 vertebral bodies. The procedure utilizes fluoroscopic guidance for a blunt guide introducer that is passed through a 15-20 mm incision lateral to the coccyx and advanced along the midline of the anterior surface of the sacrum. A guide pin is introduced and tapped into the sacrum. A series of graduated dilators are passed along the guide pin to open a working channel for the passage of instruments. After debulking the nucleus pulposis, bone graft material is injected to fill the disc space. A threaded rod designed to restore disc and neural foramen height is then secured in place. This procedure can be performed at 2 levels.

Surgeon experience with this technique is limited and complication rates are unknown. Complications may include perforation of the bowel and injury to blood vessels and/or nerves as well as infection. Since the procedure uses fluoroscopic guidance, the length of a procedure can expose the individual to high doses of radiation.

Anterior:The front surface of the body.

Axial skeleton (as related to the human body): Is comprised of the vertebral column, the spine and much of the skull.

Fluoroscopy: Imaging technique to obtain real-time moving images of the internal structures of the body; this imaging uses an x-ray source and fluorescent screen; modern fluoroscopes couple the screen to an x-ray image intensifier and video camera allowing the images to be recorded and shown on a monitor.

Presacral: Anterior to the sacrum.

Spondylolisthesis: A forward dislocation of one vertebra over the one beneath it producing pressure on spinal nerves. 

The following codes for treatments and procedures applicable to this document are included below for informational purposes.  Inclusion or exclusion of a procedure, diagnosis or device code(s) does not constitute or imply member coverage or provider reimbursement policy.  Please refer to the member's contract benefits in effect at the time of service to determine coverage or non-coverage of these services as it applies to an individual member.

When services are Investigational and Not Medically Necessary:

Peer Reviewed Publications:

1. Aryan HE, Newman CB, Gold JJ, et al. Percutaneous axial lumbar interbody fusion (AxiaLIF) of the L5-S1 segment: initial clinical and radiographic experience. Minim Invasive Neurosurg. 2008; 51(4):225-230.
2. Marotta N, Cosar M, Pimenta L, Khoo LT. A novel minimally invasive presacral approach and instrumentation technique for anterior L5-S1 intervertebral discectomy and fusion: technical description and case presentations. Neurosurg Focus. 2006; 20(1)E9.
3. Patil SS, Lindley EM, Patel VV, Burger EL. Clinical and radiological outcomes of axial lumbar interbody fusion. Orthopedics. 2010; 33(12):883.
4. Shen FH, Samartzis D, Dip EBHC, et al. Minimally invasive techniques for lumbar interbody fusion. Orthop Clin N Am. 2007; 38(373-386).

Government Agency, Medical Society, and Other Authoritative Publications: 

1. U.S. Food and Drug Administration Center for Devices and Radiological Health. Premarket Notification [510(K)] Summary. TranS1® AxiaLIF® Fixation System. Available at: http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfPMN/pmn.cfm?ID=26639. Accessed on March 28, 2011.

AxiaLIF®
Axial lumbar interbody fusion

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