|Subject:||Axial Lumbar Interbody Fusion|
|Policy #:||SURG.00111||Current Effective Date:||06/28/2016|
|Status:||Reviewed||Last Review Date:||05/05/2016|
This document addresses axial or presacral lumbar interbody fusion, 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.
Axial lumbar interbody fusion (axial LIF) is a percutaneous technique utilizing a paracoccygeal approach and trans-sacral instrumentation to stabilize the L4 to S1 or L5 to S1 spinal segment(s) that has been proposed as a method of achieving fusion with reduced complications compared to open spinal fusion surgery. The AxiaLIF® and the AxiaLIF® II or 2-Level Systems (Baxano Surgical Inc, Raleigh, NC) are cleared for marketing through the U.S. Food and Drug Administration (FDA) 510(k) process. The Premarket Notification (PMA) 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 L4-S1 or L5-S1 in conjunction with legally marketed facet or pedicle screw systems.
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 individuals had extreme lateral interbody fusion combined with posterior instrumentation, and 10 individuals 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. A total of 32 individuals had radiographic evidence of stable cage placement and fusion at last follow-up. Patil and colleagues (2010) reported a retrospective review of 50 individuals treated with AxiaLIF. A total of 4 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, visual analog scores (VAS) 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 two 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.
Tobler and colleagues (2011) published 24-month follow-up results from a large retrospective case series of 156 individuals from 4 clinical sites who underwent AxiaLIF procedures at L5-S1. Participants with a primary diagnosis of degenerative disc disease (61.5%), spondylolisthesis (21.8%), revision surgery (8.3%), herniated nucleus pulposus (8.3%), spinal stenosis (7.7%), or other (8.3%) had preoperative and postoperative radiographic imaging. Back pain was evaluated on an 11-point scale and functional impairment with the Oswestry Disability Index (ODI) preoperatively and at 24 months. Mean pain scores improved from 7.7 ± 1.6 (n=155) preoperatively to 2.7 ± 2.4 (n=148) at 24 months, reflecting an approximate 63% overall improvement (p<0.001). Mean ODI scores improved from 36.6 ± 14.6% (n=86) preoperatively to 19.0 ± 19.2% (n=78) at 24 months, or approximately 54% (p<0.001). The 2-year clinical success rates on the basis of change relative to baseline of at least 30% were 86% (n=127 of 147) and 74% (n=57 of 77) for pain and function, respectively. The overall radiographic fusion rate at 2 years was 94% (n=145 of 155). Limitations of this study include the retrospective design, lack of a control group, and potential for selection bias as the analysis only reported on participants who had 24 months of follow-up.
Zeilstra and colleagues (2013) conducted a retrospective review of 131 AxiaLIF procedures (L5-S1) performed at a single institution over a timeframe of 6 years. All individuals had undergone a minimum of 6 months (mean, 5 years) of nonsurgical management for symptomatic, refractory degenerative disc disease. Outcome measures included back and leg pain severity, ODI score, working status, analgesic medication use, self-reported satisfaction with the procedure, and complications. Computed tomography (CT) was used to determine postoperative fusion status. No intraoperative complications were reported. At a mean follow-up of 21 months (minimum, 1 year), back pain and leg pain severity decreased by 51% (VAS, 70 to 39) and 42% (VAS, 45 to 26), respectively (p<0.001). With clinical success defined as improvement of 30% or more, 66% of individuals experienced improvement in back and leg pain severity. Employment rate increased from 47% to 64% at follow-up. The fusion rate by CT was 87.8%, 9.2% indeterminate on radiograph, and 3.1% showing pseudoarthrosis. During follow-up, 17 (13.0%) individuals underwent 18 reoperations on the lumbar spine, including pedicle screw fixation (n=10), total disc replacement of an uninvolved level (n=3), facet screw fixation (n=3), facet screw removal (n=1), and interbody fusion at L4-L5 (n=1). A total of 8 (6.1%) reoperations were at the index level. As all individuals underwent fusion at L5-S1, no conclusions can be drawn regarding the effectiveness or safety of a 2-level AxiaLIF procedure. Limitations of this study include the retrospective nature of the analysis and the mean follow-up of 21 months. Additional study with long-term analysis is required to determine the durability of AxiaLIF procedures for the treatment of symptomatic, refractory degenerative disc disease.
Whang and colleagues (2013) retrospectively compared the radiographic fusion rates and adverse events for 96 individuals who underwent L5-S1 interbody fusions through either a standard anterior retroperitoneal approach or use of the AxiaLIF System in conjunction with supplemental posterior fixation. Hospital medical records were reviewed for personal data, procedural information, and complications. Multiplanar computed tomography images were evaluated by 2 independent observers to assess fusion success at 24 months using a 4-point grading scale. All facility sites were queried regarding the occurrence of any device-related adverse events. According to the radiographic analysis, the arthrodesis rates recorded for the anterior lumbar interbody fusion (ALIF) and AxiaLIF cohorts were 79% and 85%, respectively (p>0.05). The numbers and types of adverse events recorded for these procedures appeared to be similar with one serious intraoperative complication (iliac artery laceration) noted in the ALIF group. Limitations of this study include the retrospective design, lack of randomization of participants or the utilization of other controls to minimize participant or procedural variability, use of a wide variety of adjunctive graft materials that may have affected the results of the radiographic assessment (that is, more individuals in the AxiaLIF group were treated with recombinant growth factors than those in the ALIF group [29 vs. 11, respectively], accounting for the higher fusion rate in the AxiaLIF group), and lack of validated instruments to assess the clinical and functional improvements of individuals following their surgeries.
Schroeder and colleagues (2015) published a systematic review of the peer-reviewed published medical literature to determine fusion rates and the safety profile of axial interbody arthrodesis of the L5-S1 spine. A total of 15 publications met the inclusion criteria; data was derived from 13 case series and 2 retrospective cohort studies. Based primarily on the retrospective case series, the authors reported a high overall fusion rate (93.15%) and a complication rate of 12.9% associated with axial interbody fusion; however, due to the limited prospective data, the actual fusion rates may be lower and complications rate may be higher than reported in the studies. To date, the authors reported no randomized controlled trials were identified in the scientific literature demonstrating an improvement in net health outcomes using axial interbody arthrodesis compared to standard surgical methods for lumbosacral junction fusion.
The National Institute for Health and Clinical Excellence (NICE) published an Interventional Procedure Guidance 387, Transaxial interbody lumbosacral fusion (2011) which states:
Current evidence on the efficacy of transaxial interbody lumbosacral fusion is limited in quantity but shows symptom relief in the short term in some patients. Evidence on safety shows that there is a risk of rectal perforation. Therefore this procedure should only be used with special arrangements for clinical governance, consent and audit or research.
In June 2015, NICE updated the 2011 procedure guidance stating:
NICE encourages further research into transaxial interbody lumbosacral fusion. Research outcomes should include fusion rates, pain and functional scores, quality of life measures and the frequency of both early and late complications. NICE may review this procedure on publication of further evidence.
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.
In 2005, the American Association of Neurological Surgeons (AANS) published guidelines for interbody techniques for lumbar fusion (Resnick, 2005), stating there was insufficient evidence to recommend a treatment standard; in addition, minimally invasive procedures were not reviewed in the guidelines. In 2014, the AANS (Mummaneni, 2014) published an update to the 2005 guidelines, reconfirming the previous findings, stating "There is no conclusive evidence demonstrating improved clinical or radiographic outcome based on the different interbody fusion techniques."
In summary, the peer-reviewed published literature reporting outcomes for axial LIF remains limited to prospective and retrospective case series, review articles, and technical reports (Gerszten, 2012; Lindley, 2011; Marchi, 2012). To date, there are no randomized controlled trials that support the efficacy and safety of axial LIF as a minimally invasive or percutaneous surgical procedure for the treatment of L5-S1 conditions. Evidence supporting improved clinical outcomes such as pain relief, improvement in function, and successful fusion rates is limited. There is insufficient evidence to evaluate whether axial LIF procedures are as effective or as safe as other surgical approaches to lumbosacral interbody fusion, due to the variable natural history of the disorder and the subjective nature of the main outcomes. In addition, there are a relatively large number of adverse event reports including the occurrence of bowel injury (for example, perforation, development of rectocutaneous fistula), chronic infection, and implant migration, (136 reports through February 26, 2016) found in a search of the FDA's Manufacturer and User Facility Device Experience (MAUDE) database for the AxiaLIF System, which raises the possibility of an increased risk of complications. Randomized controlled studies with larger numbers of participants reporting improved clinical outcomes and a decrease in overall complication rates are needed to determine the long term efficacy and safety of axial LIF for any indication.
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 millimeter (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.
Complications after an axial LIF procedure 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:
|22586||Arthrodesis, pre-sacral interbody technique, including disc space preparation, discectomy, with posterior instrumentation, with image guidance, includes bone graft when performed, L5-S1 interspace|
|0195T||Arthrodesis, pre-sacral interbody technique, disc space preparation, discectomy, without instrumentation, with image guidance, includes bone graft when performed; L5-S1 interspace|
|0196T||Arthrodesis, pre-sacral interbody technique, disc space preparation, discectomy, without instrumentation, with image guidance, includes bone graft when performed; L4-L5 interspace (List separately in addition to code for primary procedure)|
|0309T||Arthrodesis, pre-sacral interbody technique, including disc space preparation, discectomy, with posterior instrumentation, with image guidance, includes bone graft, when performed, lumbar, L4-L5 interspace (List separately in addition to code for primary procedure)|
|0SG03A0||Fusion of lumbar vertebral joint with interbody fusion device, anterior approach, anterior column, percutaneous approach|
|0SG13A0||Fusion of 2 or more lumbar vertebral joints with interbody fusion device, anterior approach, anterior column, percutaneous approach|
|0SG33A0||Fusion of lumbosacral joint with interbody fusion device, anterior approach, anterior column, percutaneous approach|
Peer Reviewed Publications:
Government Agency, Medical Society, and Other Authoritative Publications:
The use of specific product names is illustrative only. It is not intended to be a recommendation of one product over another, and is not intended to represent a complete listing of all products available.
|Reviewed||05/05/2016||Medical Policy & Technology Assessment Committee (MPTAC) review. Updated Rationale and References sections. Removed ICD-9 codes from Coding section.|
|Reviewed||05/07/2015||MPTAC review. Updated Rationale and References sections. Format changes throughout document.|
|Reviewed||05/15/2014||MPTAC review. Updated Rationale, Background, and Reference sections.|
|Reviewed||05/09/2013||MPTAC review. Updated Rationale, References, and Index.|
|01/01/2013||Updated Coding section with 01/01/2013 CPT changes.|
|Reviewed||05/10/2012||MPTAC review. Rationale and References updated.|
|Reviewed||05/19/2011||MPTAC review. Rationale and References updated.|
|Reviewed||05/13/2010||MPTAC review. References updated.|
|New||05/21/2009||MPTAC review. Initial document development.|