Professional Statements and Societal Positions Guidelines
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.
1. In disc herniation who fulfill criteria for discectomy. The NASS recommends fusion for individuals who meet any of the following criteria:
a. primary extraforaminal disc herniation is present at L5-S1, in which a far lateral approach is not feasible because of the presence of the iliac wings.
b. primary foraminal disc herniation for which facet resection is necessary to retrieve the disc, which will result in iatrogenic instability.
c. recurrent disc herniation.
d. primary disc herniation in the lumbar spine that is at the level of the spinal cord (i.e., low lying conus medullaris).
e. lumbar spinal fusion is not recommended as an adjunct to primary excision of a central or posterolateral disc herniation at any level in the absence of instability or spondylolisthesis.
2. In lumbar spinal stenosis who fulfill criteria for decompression. The NASS recommends fusion for individuals who meet any of the following criteria:
a. dynamic instability is present, as documented by flexion-extension radiographs or comparison of a supine and upright image, defined as a difference in translational alignment between vertebrae greater than 2 mm between views
b. spondylolisthesis (defined as at least 1-2 mm of anterolisthesis of the upper vertebra in relation to the lower vertebra) is present, either isthmic (i.e., secondary to a posterior arch stress fracture) or degenerative type
c. cases in which decompression will likely result in iatrogenic instability, such as foraminal stenosis, during which greater than 50 percent of the facet joint will be removed to adequately decompress the exiting nerve root.*
d. adjacent level disease, (e.g., stenosis) that has developed above or below a previous fusion
e. recurrent stenosis (e.g., that which developed at a level that has been previously operated)
*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 non-destabilizing 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.
3. In individuals with pseudarthrosis in the lumbar spine. The NASS recommends fusion for individuals who meet all of the following criteria (a-d) or demonstrate presence of a gross failure of the instrumentation (e.g., pedicle screw breakage, screw loosening, curve/correction decompensation):
a. mechanical low back pain that is approximately at the level of the pseudarthrosis, qualified as pain that can be somewhat positionally abated
b. a period of time following the index surgery during which the individual had symptomatic relief
c. nonoperative care for at least six (6) months
d. CT or plain films that are highly suggestive of nonunion at a lumbar segment at which a fusion had been previous attempted. These criteria include:
1. Lack of bridging bone
2. Dynamic motion noted on flexion-extension radiographs
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)."
American Association of Neurological Surgeons and Congress of Neurological Surgeons
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).
Table 13. Guidelines on Fusion Procedures for the Lumbar Spine
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
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.
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.
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.
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.
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.
There was insufficient evidence to recommend a standard fusion technique.
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.
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.
DDD: degenerative disc disease; GOR: grade of recommendation; LOE: level of evidence.
The 2 associations also provided recommendations on:
- Assessment of functional outcome following lumbar fusion (part 2),
- Assessment of economic outcome (part 3),
- Radiographic assessment of fusion status (part 4),
- Correlation between radiographic outcome and function (part 5),
- Interbody techniques for lumbar fusion (part 11),
- Pedicle screw fixation as an adjunct to posterolateral fusion (part 12),
- Injection therapies (part 13),
- Brace therapy (part 14),
- Electrophysiologic monitoring (part 15),
- Bone growth extenders and substitutes (part 16), and
- Bone growth stimulators (part 17).
American Academy of Orthopaedic Surgeons
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.
- Observation is appropriate when the curve is mild (<25°) or if the child is near skeletal maturity.
- The goal of bracing is to prevent scoliotic curves from worsening. Bracing can be effective if the child is still growing and has a spinal curvature between 25° and 45°. There are several types of braces, most being the underarm type.
- Surgery may be recommended if the curve is greater than 45° and the child is still growing. If the individual has reached skeletal maturity, surgery may still be recommended for scoliotic curves that exceed 50° to 55°. An implant made up of rods, hooks, screws, and/or wires is used to straighten the spine. Bone graft from the bone bank, or from the individual's hip region, is also used to help the operated portion of the spine heal solid.
- At present, the main research focus in idiopathic scoliosis is an investigation into genetic factors as a cause of scoliosis.
National Institute for Health and Care Excellence
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.
International Scientific Society on Scoliosis Orthopaedic and Rehabilitation Treatment (SOSORT)
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.
U.S. Preventive Services Task Force Recommendations
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.