Lumbar spinal fusion (arthrodesis) is a surgical technique that involves fusing 2 or more lumbar vertebrae using local bone, autologous bone taken from the iliac crest of the individual, allogeneic donor bone, or bone graft substitutes.
Lumbar spinal fusion may be considered medically necessary for any one of the following conditions:
Conservative nonsurgical therapy for the duration specified should include the following:
“Severely restricted functional ability” should generally include loss of function and/or documentation of inability or significantly decreased ability to perform normal daily activities of work, school, or at-home duties.
Persistent debilitating pain is defined as:
Lumbar spinal fusion is considered investigational if the sole indication is any one of the following conditions:
Lumbar spinal fusion is considered not medically necessary for any indication not addressed above.
Multiple-level lumbar spinal fusion is considered not medically necessary when the criteria listed above are not met for all levels.
Practice Guidelines and Position Statements
North American Spine Society
The North American Spine Society (NASS; 2014) published coverage policy recommendations for lumbar fusion and made the following recommendations.
*For cases in which there is severe foraminal stenosis, adequate decompression often can require aggressive resection one or both facet joints at a particular level. Removal of an entire facet joint, even unilaterally, is generally thought to be a destabilizing event in the lumbar spine. While most cases of unilateral foraminal stenosis can be adequately decompressed with a nondestabilizing procedure, such as a foraminotomy, there are some cases in which the compression can be so severe and the orientation of the joint is such that achieving adequate decompression without producing iatrogenic instability can be difficult, if not dangerous to the underlying nerve root. This is a particular clinical scenario that would be exceedingly difficult to study that will likely not be addressed by a prospective, randomized trial (or other comparative trial for that matter). Recognizing this limitation in the evidence, that will likely persist, evidence-based medicine surgeons have made it clear that this should be reserved as a potential indication for fusion in the setting of stenosis without obvious signs of preoperative spondylolisthesis or instability.
Specific criteria were described for infection, tumor, traumatic injuries, deformity (e.g., scoliosis), stenosis, disc herniations, synovial facet cysts, discogenic low back pain, and pseudoarthrosis. NASS isolated situations where lumbar fusion would not be indicated: disc herniation in the absence of instability or spondylolisthesis; stenosis in the absence of instability; foraminal stenosis or spondylolisthesis; and discogenic low back pain.
Other 2014 guidelines from NASS addressed the diagnosis and treatment of degenerative lumbar spondylolisthesis. NASS gave a grade B recommendation to surgical decompression with fusion for the treatment of individuals with symptomatic spinal stenosis and degenerative lumbar spondylolisthesis to improve clinical outcomes compared with decompression alone. A grade C recommendation was given to decompression and fusion as a means to provide satisfactory long-term results for the treatment of individuals with symptomatic spinal stenosis and degenerative lumbar spondylolisthesis.
The 2011 NASS guidelines (updated in 2013) addressed multidisciplinary spine care for adults with a chief complaint of degenerative lumbar spinal stenosis. The guidelines indicated that the nature of the pain and associated individual characteristics should be more typical of a diagnosis of spinal stenosis than a herniated disc. NASS addressed whether the addition of lumbar fusion to surgical decompression improved surgical outcomes in the treatment of spinal stenosis compared with treatment by decompression alone. NASS gave a grade B recommendation (fair evidence) to decompression alone for individuals with leg predominant symptoms without instability.
The 2012 NASS guidelines (updated in 2014) addressed multidisciplinary spine care for the diagnosis and treatment of lumbar disc herniation with radiculopathy. The guidelines indicated that “there is insufficient evidence to make a recommendation for or against fusion for specific individual populations with lumbar disc herniation with radiculopathy whose symptoms warrant surgery. Recommendation: I (Insufficient Evidence).”
The 2014 guidelines from American Association of Neurological Surgeons and Congress of Neurological Surgeons addressed fusion procedures for the lumbar spine. These guidelines indicated that there was no evidence that conflicted with the recommendations formulated in the 2005 guidelines for fusion procedures for the lumbar spine (see Table 13).
|One- or 2-level degenerative disease without stenosis or spondylolisthesis (part 7)|
|Lumbar fusion should be performed for individuals whose low back pain refractory to conservative treatment (physical therapy or other nonoperative measures) and is due to 1- or 2-level DDD without stenosis or spondylolisthesis||B||Multiple level II studies|
|Discography degenerative disease of the lumbar spine (part 6)|
|Discoblock “(a procedure that involves injecting the disc with an anesthetic agent instead of a contrast agent in an effort to eliminate as opposed to reproducing a individual’s pain)” is considered as a diagnostic option during the evaluation of an individual presenting with chronic low back pain, but that the potential for acceleration of the degenerative process be included in the discussion of potential risks.||C||Single level II study|
|Disc herniation and radiculopathy (part 8)|
|Lumbar spinal fusion is not recommended as routine treatment following primary disc excision in individuals with a herniated lumbar disc causing radiculopathy.||C||IV|
|Lumbar spinal fusion is recommended as a potential option in individuals with herniated discs who have evidence of significant chronic axial back pain, work as manual laborers, have severe degenerative changes, or have instability associated with radiculopathy caused by herniated lumbar discs.||C||IV|
|Reoperative discectomy combined with fusion is recommended as a treatment option in individuals with a recurrent disc herniations associated with lumbar instability or chronic axial low back pain.||C||III|
|Stenosis and spondylolisthesis (part 9)|
|Surgical decompression and fusion is recommended as an effective treatment alternative for symptomatic stenosis associated with degenerative spondylolisthesis in individuals who desire surgical treatment.||B||II|
|There was insufficient evidence to recommend a standard fusion technique.||Insufficient|
|Stenosis without spondylolisthesis (part 10)|
|Surgical decompression is recommended for individuals with symptomatic neurogenic claudication due to lumbar stenosis without spondylolisthesis who undergo surgical intervention.||B||II/III|
|In the absence of deformity or instability, lumbar fusion is not recommended because it has not been shown to improve outcomes in individuals with isolated stenosis.||C||IV|
DDD: degenerative disc disease; GOR: grade of recommendation; LOE: level of evidence.
The 2 associations also provided recommendations on:
Information updated in 2015 by the American Academy of Orthopaedic Surgeons has indicated that the type of treatment required for idiopathic scoliosis in children and adolescents depends on the type and degree of the curve, child’s age, and number of remaining growth years until the child reaches skeletal maturity.
The National Institute for Health and Care Excellence (NICE; 2017) provided guidance on lateral interbody fusion for lumbar spine low back pain. NICE stated that lumbar fusion may be appropriate for “people with severe, life-limiting, chronic low back pain that does not respond to conservative treatments.” The evidence on lateral interbody fusion was considered “adequate in quality and quantity.” Also in 2017, NICE reexamined lumbar disc replacement and reported higher complication rates were found in individuals who underwent fusion. The conclusion was that disc replacement was not warranted and spinal fusion for nonspecific low back pain should only be performed as part of a randomized controlled trial.
The International Scientific Society on Scoliosis Orthopaedic and Rehabilitation Treatment (SOSORT) updated their guidelines on treatment of idiopathic scoliosis in 2018. In these guidelines, fusion is discussed in the context of other treatments, as an outcome measure indicating treatment failure.
Adolescent Idiopathic Scoliosis: The US Preventive Services Task Force updated their recommendations on screening for adolescent idiopathic scoliosis in 2018 and concluded that the current evidence is insufficient to assess the balance of benefits and harms of screening for adolescent idiopathic scoliosis in children and adolescents aged 10 to 18 years (I statement). The Task Force found no studies of surgical treatment in screening-relevant populations that met inclusion criteria.