Compliance with the provisions in this LCD may be monitored and addressed
through post payment data analysis and subsequent medical review audits.

**History/Background and General Information**

**Covered Indications**

**A. Cervical fusion surgery is considered medically reasonable and necessary
for the decompression of symptomatic cervical nerve root impingement when all
of the following requirements are met:**

  1.     1. Persistent or recurrent moderate or severe arm pain (4 or more on the visual analog scale or equivalent) present for a minimum of 12 weeks within the current episode of neck pain with documented failure to respond to multimodal conservative management (as tolerated) in the absence of exceptional circumstances (below) **AND**
    2. Nerve compression negatively impacts activities of daily living **AND**
    3. All other potential sources of pain/neurological deficit have been excluded **AND**
    4. Imaging (MRI or CT) evidence of central, lateral recess or foraminal stenosis at the level corresponding with clinical myotome signs or symptoms and including at least one of the following: 
      1. Cervical degenerative disc disease as indicated by the presence of one or more of the following findings: herniated nucleus pulposus, narrowing of the intervertebral disc, disc osteophytes, facet hypertrophy, or synovial cysts.
      2. Tumors (primary or metastatic)
      3. Post infection radiographic findings 
      4. Spinal instability as defined by subluxation or translation more than 3.5 mm on static lateral views or dynamic radiographs OR sagittal plane angulation of more than 11 degrees between adjacent segments.1

Limitations

The following is considered not reasonable and necessary for the decompression
of symptomatic cervical nerve root impingement:

  1. Isolated chronic axial cervical pain

_Exceptions to conservative therapy requirement for decompression of
symptomatic cervical nerve root impingement:_

  1. Myelopathy 
    1. Cervical myelopathy class III or above **OR**
    2. Progression of neurological deficits during the trial of conservative treatment.
  2. Radiculopathy 
    1. Presenting with progressive motor weakness **OR**
    2. Significant motor weakness interfering with ADLs
    3. Severe radicular pain defined as pain limiting ability to perform activities of daily living (AOLs) and 7/10 on VAS or equivalent scale2 AND associated with confirmatory imaging (computed tomography, magnetic resonance imaging) and clinical-radiological correlation.
  3. Cauda equina syndrome

**B. Cervical fusion surgery is considered reasonable and necessary for the
decompression of symptomatic cervical canal stenosis when the following
requirements are met:**

1\. Persistent or recurrent moderate or severe arm pain (4 or more on the
visual analog scale (VAS) or equivalent) present for a minimum of 12 weeks
within the episode of arm pain with documented failure to respond to
multimodal conservative management (as tolerated) in the absence of
exceptional circumstances (below) **OR**

2\. Nerve compression negatively impacts activities of daily living **OR**

3\. Spastic gait, loss of manual dexterity, problems with sphincter control
**AND**

4\. All other potential sources of pain/neurological deficit have been
excluded **AND**

5\. Imaging (MRI or CT) evidence of central stenosis at the level
corresponding with clinical signs or symptoms and including at least one of
the following:

  1.     1. Cervical degenerative disc disease as indicated by the presence of one or more of the following findings: herniated nucleus pulposus, narrowing of the intervertebral disc, disc osteophytes, facet hypertrophy, or synovial cysts.
    2. Congenital short pedicles
    3. Tumors (primary or metastatic)
    4. Post infection radiographic findings
    5. Ossification of the posterior longitudinal ligament.
    6. Spinal instability as defined by subluxation or translation more than 3.5 mm on static lateral views or dynamic radiographs OR sagittal plane angulation of more than 11 degrees between adjacent segments.
    7. Cord compression with or without increased cord signal. 

**Limitations**

**The following are considered not reasonable and necessary for**
**decompression of symptomatic cervical canal stenosis:**

  1. Isolated chronic axial cervical pain.
  2. Asymptomatic myelopathy (regardless of severity on imaging findings).

_Exceptions to conservative therapy requirement for decompression of
symptomatic cervical canal stenosis:_

  1. Myelopathy 
    1. Cervical myelopathy class III or above **OR**
    2. Progression of neurological deficits during the trial of conservative treatment.
  2. Radiculopathy 
    1. Presenting with progressive motor weakness **OR**
    2. Significant motor weakness interfering with ADLs **OR**
    3. Severe radicular pain defined as pain limiting ability to perform activities of daily living (AOLs) and 7/10 on Visual Analog Scale (VAS) or equivalent scale2 AND associated with confirmatory imaging (computed tomography, magnetic resonance imaging) and clinical-radiological correlation.

  3. Cauda equina syndrome

**C. Cervical fusion surgery is considered reasonable and necessary for the
decompression or stabilization of the cervical spine for the following
indications:**

1\. Traumatic injuries including fractures, dislocations, facture-
dislocations, or traumatic ligamentous disruption when3:

  1.     1. Fractures or dislocations which are likely to result spinal instability without neurological defects **OR**
    2. Fractures or dislocations associated with neurological defects at the affected level **OR**
    3. Instability is present.

2\. Spinal tumors involving the spine or spinal canal when:3

  1.     1.       1. Malignant or benign tumors which have caused instability or neurologic deficit where treatment of the tumor will likely require stabilization of the spine.4 **OR**
      2. Expected treatment of the tumor whether by chemotherapy or radiation therapy or surgery will likely cause spinal instability or neurologic deficits.4 **OR**
      3. Instability is present.

3.Infection involving the spine in the form of discitis, osteomyelitis, or
epidural abscess when3:

  3. Imaging or other studies (MRI, biopsy, bone aspirate) demonstrating infection **AND**
  4. Imaging evidence of vertebral body destruction OR documentation that spinal debridement will cause vertebral instability5,6 **OR**
  5. Instability is present.

4\. Deformities that include the cervical spine including when3:

  1. Cervical kyphosis associated with cord compression or Atlantoaxial (C1-C2) subluxation or Basilar invagination of the odontoid process into the foramen magnum; _or_ Subaxial (C2-T1) instability kyphosis, head drop syndrome, post-laminectomy deformity OR
  2. Symptomatic pseudarthrosis (non-union of prior fusion) with radiological (e.g., CT or MRI) demonstration of non-union of prior fusion (lack of bridging bone or abnormal motion at fused segment) after 12 months since fusion surgery _or_ with radiographic evidence of hardware failure (fracture or displacement). OR
  3. Spinal instability after laminectomy **OR**
  4. Rheumatoid arthritis with associated instability **OR**
  5. Cervical degenerative spondylolisthesis with spinal instability (Anterolisthesis/Posterolisthesis)

**AND**

f. Substantial functional limitation is present such as severe neck pain,
difficulty ambulating and decrease ability to perform ADLs or ability to
maintain forward gaze.

**AND**

g. Progression of deformity

**Limitations**

Cervical Fusion for the decompression or stabilization of the cervical spine
**** is not reasonable and necessary when all the above criteria are not
fulfilled.

**Provider Qualifications**

The Medicare Program Integrity Manual states services will be considered
reasonable and necessary only if performed by appropriately trained providers.

Patient safety and quality of care mandate that healthcare professionals who
perform cervical fusion are appropriately trained and credentialed by a formal
residency/fellowship program. Credentialing or privileges are required for
procedures performed in inpatient and outpatient settings.

All aspects of care must be within the provider's medical licensure and scope
of practice. Reimbursement for procedures utilizing imaging techniques may be
made to providers who meet training requirements for the procedures in this
policy only if their respective state allows such in their practice act and
formally licenses or certifies the practitioner to use and interpret these
imaging modalities (ionizing radiation and associated contrast material,
magnetic resonance imaging, ultrasound). At a minimum, training must cover and
develop an understanding of anatomy and drug pharmacodynamics and kinetics as
well as proficiency in diagnosis and management of disease, the technical
performance of the procedure, and utilization of the required associated
imaging modalities.

**Notice:** Services performed for any given diagnosis must meet all the
indications and limitations stated in this LCD, the general requirements for
medical necessity as stated in CMS payment policy manuals, all existing CMS
national coverage determinations, and all Medicare payment rules.

****

**Definitions**

**Acute Pain** ** - **an unpleasant sensory and emotional experience
associated with actual or potential tissue damage which is present for up to 6
weeks.7

**Baseline Pain-** An initial measurement of the pain which is taken at a
specified time point and used for comparison over time to look for changes in
the pain levels.

**Cervical Radiculopathy-** Pain in a radicular pattern in one or both upper
extremities related to compression and irritation of one or more cervical
nerve roots.8

**Chronic Pain** ** - **The temporal definition of pain persisting at least 12
weeks after the onset of the acute pain.

**Conservative Therapy** ** - **Consists of an appropriate combination of
medication in therapeutic dosages (e.g., non-steroidal anti-inflammatory
[NSAIDs], serotonin and norepinephrine reuptake inhibitors (SNRIs),
analgesics, etc.) administered for a sufficient amount of time to determine
efficacy, in combination with either physical therapy, spinal manipulation
therapy, cognitive behavioral therapy (CBT), home exercise program,
acupuncture, or other interventions based on the individual's specific
presentation, physical findings, and imaging results.

**Consistent Improvement - **The progressive, incremental, and clinically
meaningful improvement of physical signs or symptoms.

**Disability** - Activity limitations or participation restrictions in an
individual with a health condition, disorder or disease.9

**Functional Impairment -** A physical or functional or physiological
impairment causing deviation from the normal function of a tissue or organ.
This results in a significantly limited, impaired or delayed capacity to move,
coordinate actions or perform physical activities and is exhibited by
difficulties in one or more of the following areas: physical and motor tasks;
independent movement; performing basic life functions.9

**GRADE** - A system developed by the GRADE Working Group to address the
shortcomings of present grading systems in healthcare. The GRADE system uses a
common, sensible, and transparent approach to grading the quality of evidence.
The results of applying the GRADE system to clinical trial data are displayed
in a table known as a GRADE profile.

**Hangman 's Fracture **\- a bilateral fracture traversing the pars
interarticularis of cervical vertebrae 2 (C2) with an associated traumatic
subluxation of C2 on cervical vertebrae 3 (C3).10

**Multidisciplinary Biopsychosocial Rehabilitation (MBR** _)_ - Targets
physical as well as psychological and social aspects of pain and involves a
team of healthcare providers with different professional backgrounds and
training. __

**Myelopathy-** An inclusive term describing a compression of the spinal cord
resulting in neurological deficits e.g., spasticity (sustained muscle
contractions), hyperreflexia, pathologic reflexes, paresthesia affecting the
extremities, muscle weakness, digit/hand clumsiness, or gait disturbance.11,12

**Nonspecific low back pain** ** - **Back pain that cannot be attributed to a
specific disease or spinal pathology **.**

**Session-** A session is a time period, which includes all procedures (e.g.,
SIJIs and RFA ablations) that are performed during the same day.

**Sustained and Constant Pain Relief** \- The pain relief must continue for
the defined time period and without interruption or regression to the primary
(index) pain.

**Symptomatic pseudarthrosis** \- (non-union of prior fusion) with
radiological (e.g., CT or MRI) demonstration of non-union of prior fusion
(lack of bridging bone or abnormal motion at fused segment) 12 months or more
since fusion surgery _or_ with radiographic evidence of hardware failure
(fracture or displacement).13

**Unstable Spine-** cervical spinal instability has been defined as
destruction of either the anterior or posterior elements of the spine making
them nonfunctional, more than 3.5 mm of displacement of one vertebra in
relation to another or greater than 11 degrees of rotational difference
between adjacent vertebrae.1,14

**Contractor Advisory Meeting**

A Multi-MAC Contractor Advisory Committee (CAC) Meeting was hosted by Noridian
and included **** Noridian Healthcare Solutions, CGS Administrators, National
Government Services, Palmetto GBA, WPS Government Health Administrators, First
Coast Service Options and Novitas Solutions on August 16, 2023. The transcript
and audio for this meeting is posted on each MACs website. Feedback from the
subject matter experts is included through the evidence summary.

_Conservative Treatment_

Treatment of cervical radiculopathy can range from conservative management to
surgery. Conservative care is considered initial management for cervical
radiculopathy from degenerative disorders as most cases will be self-limited
and resolve spontaneously over a variable length of time without specific
intervention.8 Conservative management for cervical radiculopathy may include
oral analgesics or short course of oral glucocorticoids, avoidance of
provocative activities, short term immobilization with cervical collar or
pillow, active physical therapy, manual therapy, and cervical traction.15,16
In a published analysis of clinical practice guidelines for neck pain and
radiculopathy the following interventions were listed as recommended
components of conservative therapy16:

  * Pharmacotherapies: analgesics, Paracetamol (Acetaminophen), NSAIDs (non-steroidal anti-inflammatory drugs), SNRIS, opioids (including tramadol), topical medications including NSAIDS.
  * Non-Pharmacologic Interventions: exercise programs/physical therapy, thermotherapy, manual therapy (combined with other treatment), acupuncture, epidural steroid injection.

Studies have shown that surgery and conservative interventions achieve similar
long-term results, and that conservative treatment is often the preferred
option because it avoids the risks of surgical treatment.8,17 A systematic
review found sufficient low-quality evidence to support the role of
conservative measures as a first-line approach for the management of cervical
radiculopathy.18 Observational data reports 40-80% of patients with cervical
radiculopathy will improve with conservative measures.15 Exercise alone or in
combination with other treatments was shown to be beneficial for cervical
radiculopathy in a systematic review and meta-analysis.19 Physical therapy
accompanied by home exercise for 6 weeks has been shown in a randomized trial
to substantially reduce neck and arm pain for patients with cervical
radiculopathy.20 A RCT compared cervical collar or physical therapy and found
improvement over a wait and see approach suggesting that an active treatment
approach results in better outcomes.21 A RCT demonstrated that patient who
proceed to surgery for management of cervical radiculopathy had more rapid
resolution of symptoms compared to those who remained in physical therapy but
outcomes at 2 years were similar and conclude structured physiotherapy should
be considered first line management.22 Further investigation with the same
author reported anterior cervical decompression and fusion (ACDF) plus PT was
superior to PT alone.23 Subject matter experts agreed that conservative
therapy is an acceptable first line approach and that there are modifiable
risk factors such as diabetes management, smoking cessation and weight loss
that can impact disease course and surgical outcomes.24

NASS Guidelines state: "As the majority of patients with cervical
radiculopathy will improve with nonoperative treatment, particularly within
three months from onset, most practitioners would agree that a 6- to 12-week
period of nonoperative care seems reasonable. Specific provisions of what
should be included during the course of nonoperative treatment were not
outlined as there is no universally agreed upon group of modalities. The types
of treatment that one would consider, however, should include physical
therapy, anti-inflammatory pain medications and epidural steroid injections."3

A multi-disciplinary, international panel established consensus-based guidance
on effective nonsurgical treatment modalities for individuals in different
stages (i.e., acute, subacute, and chronic) of cervical radiculopathy.25 These
guidelines include patient education with positive reinforcing and non-nocebo
content, spinal manipulative therapy, exercise, sustaining pain-relieving
positions, cognitive behavioral therapy, general aerobic exercise, strength
training, postural education and workplace and vocational/ergonomic
assessment.

Berman, et al compared the American College of Radiology appropriateness
criteria for MRI to the specific criteria in 56 commercial policies and
clinical management organizations in the USA, for neck pain both with and
without radicular symptoms.26 While the focus was on coverage criteria for
MRIs, the study also summarized organizational positions on conservative care.

  * Different definitions of conservative care are used e.g., "a multimodality approach consisting of a combination of active and inactive components" and "a combination of strategies to reduce inflammation, alleviate pain, and improve function."
  * All organizations require the failure of at least six weeks of conservative management. Some organizations require conservative management within the preceding 3 or 6 months, while others do not specify how recently conservative treatment needs to take place.
  * Conservative interventions are 'provider-directed treatment' that includes education, activity modification, nonsteroidal anti-inflammatory (NSAIDs), narcotic and non-narcotic analgesic medications, oral or injectable corticosteroids, a provider-directed home exercise/stretching program, cross-training, avoidance of aggravating activities, physical/occupational therapy, spinal manipulation, interventional pain procedure, and other pain management techniques. Only a single organization requires two separate forms of conservative treatment, although the guidelines do not specify what these are.

**Imaging Modalities**

North American Spine Society (NASS)8 Evidence-Based Clinical Guidelines on the
Diagnosis and Treatment for Cervical Radiculopathy from Degenerative Disorders
state MRI is the recommended study for correlative compressive lesions in
cervical spine patients who have failed conservative therapy and being
considered for intervention based on Grade B recommendation. The consensus of
the group was that CT can be considered in those who have a contraindication
to MRI. Computed tomography myelography was recommended for patients with
discordant findings on MRI or contraindication to MRI based on Grade B
Recommendation. There was insufficient evidence to make a recommendation for
or against the use of electromyography (EMG) for cervical radiculopathy
evaluation.

**__**

**Cervical Radiculopathy**

Cervical radiculopathy is a common condition that usually occurs when a nerve
root is inflamed by a herniated disc or bone spur. As a result, the inflamed
nerve root may result in neck pain, numbness or muscle weakness and sensory
symptoms. This condition impacts approximately 85 out of 100,000 people.27

**_Clinical Outcomes_**

Seven evidence syntheses with publication dates ranging from 2016-2022 that
assessed clinical outcomes were identified.28-34 Two reviews included only
RCTs.28,30 Four studies included both non-randomized studies of interventions
(NRSI) and a small number (range 1-6) of RCTs.29,31-33 The number of primary
studies in the syntheses ranged from 7-23, with generally small sample sizes.
Half the studies diagnosed participants with single-level, unilateral cervical
radiculopathy. Comparators included different fusion techniques, foraminotomy,
arthroplasty, and conservative interventions. Anterior cervical discectomy and
fusion was an intervention in each study. Timing to follow-up ranged from 24
to 47 months.

Broekema, et al. (2020) conducted a systematic review with meta-analysis that
included 1,567 participants described in 21 RCTs.28 Thirteen of the studies
had data from less than 100 participants. The clinical effects of ACDF were
compared with posterior cervical foraminotomy (PCF), anterior cervical
discectomy without intervertebral spacer (ACD), ACD with poly-
methylmethacrylate as an intervertebral spacer (PMMA), autologous bone graft
(ABG), ACDF with autologous bone graft plus plating (ABGP), cervical disc
arthroplasty (CDA), and physical therapy. ACDF had a significantly better
success rate compared to ACD. Among the remaining comparisons, there were no
significant differences in success rates. Six subgroup comparisons found no
significant differences in work status across interventions. Aside from a
significant effect favoring ACDF over CDA, there were no differences in
disability outcomes at mean follow-up. Improvement in arm pain favored ACDF
with a cage over ABGP, ACD over ACDF with a cage, and ACDF over CDA. The
clinical significance of these differences was not described. Limitations in
this evidence synthesis included an overall high risk of bias (only 3 of 21
included studies had a low risk of bias), indirectness (the mean age across
studies was 43.8 years), and imprecision due to the small sample sizes across
sizes, with 62% of studies having less than 100 participants.

Fang, et al. (2020) included 3 RCTs and 12 NRSI with a total of 52,705 (~51K
from a single cohort study) participants diagnosed with single-level
unilateral cervical radiculopathy in a systematic review with meta-analysis.
Outcomes comparing ACDF with PCF were measured at a mean of 47 months.29 No
statistically significant differences were identified for measures of
disability (function), neck pain, arm pain, or satisfaction. Limitations
impacting the certainty of the evidence included inherent drawbacks due to
most of the primary study designs (12 of 15 studies were retrospective cohort
designs) and the 3 RCTs either did not contribute to or contributed minimally
to the pooled analyses, indirectness (the mean ages across studies ranged from
39 to 53.8 years), and significant heterogeneity was observed in subgroup
analyses of ACDF vs. PCF using open and minimally invasive techniques.

In a network meta-analysis, Gao, et al. (2022) performed direct and indirect
comparisons of ABG, ACD, ACF, PCF, ACDFP (ACDF plus plating), CDA, PMMA, and
physical therapy.30 Twenty-three RCTs (N=1,844) were assessed at a mean of 26
months. There were no statistical differences among the different
interventions in measures of success rate, arm/neck pain, or disability. There
were limitations in this network meta-analysis including an overall high risk
of bias (only 13% [3 of 23] of the studies had a low risk of bias),
indirectness (the mean/median age among the included studies ranged from 41 to
50.5 years and only 2 of 23 studies were conducted within the United States),
imprecision (sample sizes were small [27-209]), and inconsistency (clinical
and statistical heterogeneity).

Goedmakers, et al. (2020) systematically reviewed 6 RCTs and 2 NRSI (N=777) in
comparing ACDF with CDA.31 Timing to follow-up in the studies ranged from 1-7
years. A single study reported a statistically significant difference between
interventions for disability; however, the difference did not achieve clinical
relevance. Another five studies found no significant difference between CDA
and ACDF. None of the studies reported a significant difference in neck pain
after 2 years post-surgery. Limitations of this systematic review included all
articles showed intermediate to high risk of bias, indirectness (mean age was
~45 years), imprecision (sample sizes were small [41-209]), and inconsistency
(high heterogeneity precluded pooling the results of individual studies).

A systematic review with meta-analysis of 658 patients (1 RCT; 11 NRSI) with
single-level cervical radiculopathy compared traditional ACDF vs. stand-alone
ACDF vs. CDA.32 The reviewers found no statistically significant differences
in disability measures at a minimum of 1 year for the different interventions.
Limitations included the drawbacks inherent in observational studies (11 of 12
included studies were cohort designs), uncertainty about the internal validity
of the studies (risk of bias of the included studies was not assessed),
imprecision (the mean sample size was 54.8), and inconsistency (high
heterogeneity was present in the pooled analysis for disability outcomes).

Liu, et al. (2016) produced a systematic review of 1,336 patients with
cervical radiculopathy (3 RCTs, 7 NRSI) who underwent either ACDF or PCF.33 At
a mean of 3.7 years following the procedure, there were no between-group
differences in patient-reported measures of pain and disability. Based on a
single study, ACDF showed a significantly higher success rate (93.6%) than the
PCF group (85.1%). Limitations of this review included the drawbacks inherent
in observational studies (7 of the 10 studies were retrospective cohort
designs), all the RCTs were judged to have a high risk of bias, and
indirectness (the mean age of the included participants was ~46 years
[39-53.3]).

Zou, et al. (2022) conducted a systematic review with a meta-analysis of 1,175
patients with unilateral cervical radiculopathy.34 One RCT and 6 NRSI compared
clinical outcomes for groups receiving ACDF or MI-PCF (minimally invasive
posterior cervical fusion). At a mean post-surgical follow-up of 47 months, no
statistically significant differences were observed in patient-reported
disability, neck pain, or arm pain. Limitations in this evidence synthesis
included those inherent in observational study designs, indirectness (the mean
age of the participants was 48.9 years), and inconsistency (high heterogeneity
was reported for arm pain outcomes).

In aggregate, the clinical effects associated with the different surgical and
conservative interventions did not result in statistically significant or
clinically relevant differences. The only exception was ACDF, which showed a
better success rate than ACD. Overall, the certainty of the evidence was
determined to be very low. Limitations included those inherent in
observational study designs, high risk of bias in most RCTs, indirectness,
imprecision, and heterogeneous outcomes.

**__**

**_Surgical Outcomes_**

Three evidence syntheses reported on perioperative measures. Operative time
was assessed in all studies.29,30,34 Length of stay (LOS) was included in two
reviews.29,34 A single study analyzed blood loss.29

Fang, et al. (2020) compared ACDF with open PCF or MI-PCF for patients with
single-level, unilateral cervical radiculopathy in a systematic review with
meta-analysis.29 The reviewers reported that compared to ACDF, open PCF had a
shorter operation time, while there was no difference between ACDF and MI-PCF.
Based on data from 2 studies, there was no significant difference in blood
loss among the surgical techniques. The PCF group was associated with a
significantly shorter length of hospitalization than the ACDF group.
Limitations impacting the certainty of the evidence included inherent
drawbacks due to most of the primary study designs (12 of 15 studies were
retrospective cohort designs) and the 3 RCTs either did not contribute to or
contributed minimally to the pooled analyses, indirectness (the mean ages
across studies ranged from 39 to 53.8 years), and significant heterogeneity
was observed in subgroup analyses of ACDF vs. PCF using open and minimally
invasive techniques.

Gao, et al. (2022) assessed operative time for different surgical procedures
in a network meta-analysis.30 Direct and indirect comparisons showed ABGP,
ACD, ACDF, and ACDFP had shorter surgery times compared with ABG. ACDF had a
shorter surgery time compared with PMMA. There were limitations in this
network meta-analysis including an overall high risk of bias (only 13% [3 of
23] of the studies had a low risk of bias), indirectness (the mean/median age
among the included studies ranged from 41 to 50.5 years and only 2 of 23
studies were conducted within the United States), imprecision (sample sizes
were small [27-209]), and inconsistency (clinical and statistical
heterogeneity).

Zou, et al. (2022) performed a systematic review with meta-analysis comparing
ACDF with MI-PCF.34 The analysis did not find any significant difference in
operative time between the two cohorts. Data from 3 retrospective studies
observed a statistically significant difference in LOS favoring MI-PCF.
Limitations in this evidence synthesis included those inherent in
observational study designs, and indirectness (the mean age of the
participants was 48.9 years).

In summary, the observed perioperative results varied by the comparators and
the type of outcome. Compared to open PCF, ACDF had significantly longer
operative time and LOS. MI-PCF also had a significantly less LOS than ACDF.
When ACDF was compared to other surgical techniques, no significant
differences were found in operative time and blood loss. The overall certainty
of the evidence was rated as very low due to the high risk of bias in the
included RCTs, limitations inherent in observational studies, and uncertainty
about the applicability of the results to the U.S. Medicare population
(indirectness).

**_Radiographic Outcomes_**

Two evidence syntheses described post-surgical radiographic results associated
with individuals diagnosed with cervical radiculopathy.32,33

Katsuura, et al. (2019) performed a systematic review with meta-analysis that
compared traditional ACDF vs. stand-alone ACDF vs. CDA.32 At a minimum of
1-year post-surgical follow-up, no significant differences in the C2-C7 (Cobb)
angle were observed. Limitations of this evidence synthesis included the
drawbacks inherent in observational studies (11 of 12 included studies were
cohort designs), uncertainty about the internal validity of the studies (risk
of bias of the included studies was not assessed), and imprecision (the mean
sample size was 54.8).

Liu, et al. (2016) systematically reviewed data from 3 RCTs and 7 NRSI,
encompassing 1,335 patients; however, only a single RCT provided data
regarding radiographic outcomes.33 The postoperative ROM of the caudal
adjacent segment was 11.33  5.07 in the ACDF group and 8.73  5.92 in the
PCF group. The significance of this difference was not described. Limitations
of this review included the drawbacks inherent in observational studies (seven
of the ten studies were retrospective cohort designs), all the RCTs were
judged to have a high risk of bias, and indirectness (the mean age of the
included participants was ~46 years [39-53.3]).

Overall, there was limited evidence concerning radiographic outcomes following
cervical fusion in patients diagnosed with cervical radiculopathy. No
significant between-group differences were reported for Cobb angle or ROM. The
overall certainty of the evidence was judged as very low due to a high/unknown
risk of bias, study design limitations, imprecise data, and indirectness.

**_Undesirable Effects_**

Six evidence syntheses described undesired effects associated with cervical
fusion surgery.28,30,31,33-35 Assessment timeframes ranged from 24 to 57
months.

Broekema, et al. (2020) performed a systematic review with meta-analysis of
1,567 participants diagnosed with cervical radiculopathy who underwent
anterior or posterior surgical interventions and were compared with other
surgical techniques.28 There was a higher complication rate in the group with
ABG from the iliac crest. This effect disappeared when donor-site
complications were left out. No other significant effect was observed in the
comparison between ACDF with ABG and ACDF with a cage. Subgroup comparisons
found no significant differences in reoperation rate across the different
surgeries. Limitations in this evidence synthesis included an overall high
risk of bias (only 3 of 21 included studies had a low risk of bias),
indirectness (the mean age across studies was 43.8 years), and imprecision due
to the small sample sizes across sizes, with 62% of studies having less than
100 participants.

Gao, et al. (2022) conducted a network meta-analysis of 23 RCTs that included
direct and indirect comparisons of ACDF, ABG, ACD, ACF, PCF, ACDFP, CDA, PMMA,
and physical therapy.30 There were no statistical differences among the
various interventions, including physical therapy for complication and
reoperation rates. There were limitations in this network meta-analysis
including an overall high risk of bias (only 13% [3 of 23] of the studies had
a low risk of bias), indirectness (the mean/median age among the included
studies ranged from 41 to 50.5 years and only 2 of 23 studies were conducted
within the United States), imprecision (sample sizes were small [27-209]), and
inconsistency (clinical and statistical heterogeneity).

Goedmakers, et al. (2020) systematically reviewed 777 participants with
cervical radiculopathy from 6 RCTs and 2 NRSI in comparing CDA to ACDF.31 The
authors concluded the reporting on the level of reoperation is heterogeneous
and incomplete; however, the results suggested reoperations were most frequent
at the adjacent level for the ACDF group and at the index level for the CDA
group. Four articles described adjacent segment disease (ASD), of which only
one article described a significantly higher incidence of ASD in ACDF
patients. No other statistically significant differences in complication rates
were described between groups. Limitations of this systematic review included
all articles showed intermediate to high risk of bias, indirectness (mean age
was ~45 years), imprecision (sample sizes were small [41-209]), and
inconsistency (high heterogeneity precluded pooling the results of individual
studies).

Gutman, et al. (2018) performed a systematic review with meta-analysis that
focused on the comparative undesired effects of participants with single-level
cervical radiculopathy who prospectively underwent ACDF, CDA, or MI-PCF.35 The
rate of revision surgery following ACDF (14.46) was greater than double that
of MI-PCF (7.00) and CDR (6.49). Compared to ACDF (21.29), the rate of adverse
events was significantly less for MI-PCF (3.00), but greater for CDA (27.27).
Limitation in this review included the risk of bias of the primary studies was
not assessed, indirectness (the mean age for each of the included studies was
less than 50 years [43-49.3]), imprecision (the number of studies was few [4],
with small sample sizes), and uncertainty concerning inconsistency
(heterogeneity was not assessed).

Liu, et al. (2016) assessed the overall complication rate in a systematic
review that compared patients who had received either ACDF or PCF.33 The mean
complication rate was 7% in the ACDF group and 4% in the PCF group. The
difference was not statistically significant. Limitations of this review
included the drawbacks inherent in observational studies (seven of the ten
studies were retrospective cohort designs), all the RCTs were judged to have a
high risk of bias, and indirectness (the mean age of the included participants
was ~46 years [39-53.3]).

Zou, et al. (2022) employed a systematic review with meta-analysis of 1,175
patients who underwent either ACDF or PCF.34 In the ACDF group, complication
rates ranged between 1.8% and 10.5%. In the MIS-PCF group, the rate was
between 0% and 14.3%. The between-group difference was not significant. The
reoperation rate was between 0-7.5% in the ACDF group and 0 -14.3% in the MIS-
PCF group. The difference was not significant. Limitations in this evidence
synthesis included those inherent in observational study designs, and
indirectness (the mean age of the participants was 48.9 years).

In aggregate, the complication rates associated with different surgical
procedures and physical therapy are generally similar; however, the rate of
adverse events with ACDF appears to be greater than MI-PCF, and the rate of
ASD is lower with CDA vs. ACDF. The overall results of the different evidence
syntheses were heterogeneous concerning reoperation rates. No significant
differences were found among the surgical interventions studied apart from a
small systematic review (Gutman, et al.; 2018) that concluded the revision
surgery rate of ACDF was double that of CDA and MI-PCF. The credibility of
these findings was very low due to a lack of quality appraisal (risk of bias)
for the included RCTs, the small numbers of studies (4) and participants
(506), uncertain applicability to the U.S. Medicare population, and omitting
an assessment of heterogeneity. Overall, the certainty of the evidence was
judged to be very low due to multiple limitations i.e., study designs,
high/unclear risk of bias, indirectness, imprecise results, and unexplained
heterogeneity.

**_Societal Input_**

The North American Spine Society (NASS) has published appropriateness criteria
for cervical fusion surgery as a treatment for cervical radiculopathy.3

Cervical radiculopathy: from degenerative disorders (either from disc
herniation or bony stenosis), as an adjunct to disc excision, that meets ALL
the following criteria:

  * Pattern of radiculopathy explained by imaging.
  * Six to 12 weeks of an appropriate course of nonoperative treatment.
  * The following can mitigate the need for an initial nonoperative trial: 
    * Severity of symptoms prevents the patient from working.
    * Functionally limiting motor weakness.

Cervical fusion may NOT be indicated in cases that do not fulfill the above
criteria including cervical radiculopathy from isolated foraminal stenosis
treated with a partial medial facetectomy/foraminotomy.

****

**Degenerative Cervical Myelopathy**

**_Clinical Outcomes_**

Six evidence syntheses with publication dates ranging from 2014-2022 that
assessed clinical outcomes were identified.36-41 Three of the syntheses
included only non-randomized studies of an intervention (NRSI).37,39,40 Three
studies included both NRSI and a small number (1-4) of RCTs.36,38,41 The
number of primary studies in the syntheses ranged from 5-18, with generally
small sample sizes. Participants were mostly diagnosed with multilevel
cervical spondylotic myelopathy (CSM). Comparators included different fusion
techniques, arthroplasty, and hybrid surgery. Anterior cervical discectomy and
fusion was an intervention in each study. Timing to follow-up was variable
(1-60+ months).

Fei, et al. (2015) conducted a systematic review with meta-analysis that
compared two fusion techniques, ACDF and ACCF (anterior cervical corpectomy
and fusion).36 Eighteen primary studies (1 RCT, 17 NRSI) were included in the
review. Outcomes were assessed at a minimum of 6 months post-operation.
Neurological status (success) and pain intensity outcomes were similar between
surgical groups. There were several limitations in this study including those
associated with observational studies (17 of 18 studies were cohort or case-
control designs), indirectness (17 of 18 studies included participants located
in China or South Korea, and all the studies had a mean/median between 32-59
years), imprecision (all studies had small sample sizes with confidence
intervals that crossed the indicator for no effect), and inconsistency of
effects across studies (significant heterogeneity for all secondary outcomes).

In a systematic review with meta-analysis, Han, et al. (2014) reported on 14
NRSI that compared ACDF and ACCF.37 At a postoperative minimum of 24 months,
all clinical measures (success rate, neurological status, pain, and function
[disability]) were statistically similar ( _p_ >0.05). Limitations of this
review involved the inclusion of only low-quality studies (all included
studies were observational cohort or case-control designs), indirectness (mean
ages ranged from 44-58.74 yrs.), imprecision (all studies had small sample
sizes and pain outcomes had small numbers of pooled data), and high
statistical heterogeneity (inconsistency) was present for functional outcomes.

Li, et al. (2019) performed a network meta-analysis that included 4 RCTs and
12 NRSI.38 The analysis included direct and indirect comparisons of ACDF,
ACCF, cervical disc arthroplasty [replacement] (CDA), and hybrid surgery. At a
mean of 33.3 months following surgery, CDA demonstrated a statistically
significant difference in disability outcomes compared to the other surgical
procedures. The clinical significance of these results was not described.
Limitations in this network meta-analysis were associated with low-quality
studies (12 of 16 studies were case-control designs), indirectness (indirect
comparisons were a core component of the methodology and 14 studies took place
in Asia [China, South Korea, Singapore]), and imprecision (all studies had
small sample sizes).

Montano, et al. (2019) systematically reviewed and meta-analyzed 5 NRSI (487
participants) with multilevel CSM.39 No difference in neurological status was
found between ACDF and laminoplasty at a mean of 35.4 months post-surgery (MD
= -0.053; 95% CI, -0.511 to 0.404; _p_ = 0.819). Limitations involved the low-
quality of all included studies (observational cohort or case-control
designs), indirectness (all studies had mean ages between 54 and 56.8 years.),
imprecision (too few events for all outcomes and wide confidence intervals for
all pooled outcomes measured).

A systematic review without meta-analysis of 11 primary studies (2 RCTs, 9
NRSI) included a total of 570 participants with single or multilevel CSM.41
Clinical outcomes were assessed between 12 and 60 months postoperatively. No
statistically significant differences in ACDF and ACCF were found for
neurological status, pain, or function (disability). Review limitations
included the overall low-quality primary study designs (9 of the 11 included
studies were observational cohort or case-control), indirectness (none of the
studies were performed in the United States and all studies had a mean age
between 46.8 and 57.7 years), imprecision (all the studies had small sample
sizes), and inconsistency (I2 test revealed high heterogeneity [>75%] across
studies for all outcomes).

Wang, et al. (2022) included 14 NRSI with wide variation in sample sizes
(40-2188) that comparatively assessed ACDF and ACCF.40 There was no between-
group difference in patient-reported function; however, improvement in
neurological status at 1-60+ months follow-up favored ACDF (OR = 0.49, 95% CI:
0.06 to 0.91; _p_ = 0.02). Limitations involved the selection of low-quality
studies (all studies were retrospective observational cohorts or case-control
designs) and indirectness (11 of the studies were conducted in Asia [China,
South Korea]).

Primary Studies

One RCT that was not included in any evidence synthesis was identified. El-
Ghandour, et al. (2020) compared ACDF with posterior laminectomy with or
without fusion in the management of degenerative cervical myelopathy (DCM).42
Sixty-eight patients (mean age 53 years) were enrolled in a 1:1 randomized
trial. Clinical outcomes were assessed after 1 year. There were significantly
better outcomes in patient-reported disability (function) and pain scores in
the ACDF group compared to posterior surgical approaches. The Nurick
myelopathy grading scale showed a nonsignificant improvement with using the
posterior approach. The authors noted several methodologic limitations
including a high risk of bias in the randomization process, small sample size,
and short-term follow-up.

In aggregate, clinical outcomes were found to be largely equivalent regardless
of surgical technique. The overall certainty of the evidence was judged to be
very low due to limitations inherent in the included study designs,
indirectness (uncertainty about the applicability to the US Medicare
population), imprecision (variability within studies in the direction and
clinical relevance of effects), and inconsistencies across studies in the
magnitude of effect.

**__**

**_Surgical Outcomes_**

A total of seven evidence syntheses evaluated surgical (perioperative) outcome
measures.36-40,43,44 All syntheses included NRSI, while RCTs were represented
in two reviews.4,5 Sample sizes were small, patients were diagnosed with
multilevel CSM, comparisons were between surgical interventions, and follow-up
assessments were variable.

Fei, et al. (2015) reported on data from 1,246 patients included in 18 primary
studies (1 RCT, 17 NRSI).38 Compared to ACCF, patients who underwent ACDF had
superior perioperative outcomes (length of stay [LOS], operative time, and
blood loss). Limitations included the preponderance of low-quality studies (17
of 18 studies were of observational designs), indirectness (17 of 18 studies
included participants located in China or South Korea, and all the studies had
a mean/median between 32-59 years), imprecision (all studies had small sample
sizes with confidence intervals that crossed the indicator for no effect), and
inconsistency (significant heterogeneity for all secondary outcomes).

Han, et al. (2014) included 15 NRSI (1,372 participants) in comparing ACDF and
ACCF.37 No significant difference in operative time was found (MD = -9.34, 95%
CI = -42.99 to 24.31; _p_ = 0.59). LOS (MD = -5.60, 95% CI = -7.09 to - 4.11;
_p_ <0.00001) and blood loss (MD = -151.35, 95% CI = -253.22 to -49.48; _p_ =
0.004) were both less (better) in the ACDF group vs. the ACCF group.
Limitations involved the low-quality of all included studies (observational
cohort or case-control designs), indirectness (mean ages ranged from 44-58.74
years), imprecision (all studies had small sample sizes), and inconsistency
(high statistical heterogeneity was present for blood loss and operative
time).

A network meta-analysis that included 1,639 patients with multilevel CSM found
that ACDF resulted in a shorter operative time compared (directly and
indirectly) to other surgical techniques (ACCF, CDA, and hybrid surgery).38
Limitations included low-quality studies (12 of 16 studies were case-control
designs), indirectness (indirect comparisons were a core component of the
methodology, 14 studies took place in Asia [China, South Korea, Singapore],
and only a single study included a U.S. population), and imprecision (all
studies had small sample sizes).

Montano, et al. (2019) compared the results of ACDF and laminoplasty in 5 NRSI
(487 patients).39 There was a statistically significant difference favoring
ACDF regarding blood loss (MD = -131.381; 95% CI, -259.522 to -3.240; _p_ =
0.044). No between-group difference was seen in operative time (MD = -10.231;
95% CI, -58.612 to 38.149; _p_ = 0.679). Limitations related to the low-
quality of included studies (all were observational cohort or case-control
designs), indirectness (all studies had mean ages between 54 and 56.8 years),
imprecision (too few events for all outcomes and wide confidence intervals for
all pooled outcomes measured), and inconsistency (high heterogeneity involving
operative time and blood loss).

A total of 5,249 patients from 14 NRSI provided data on surgical outcomes for
a systematic review with meta-analysis.40 Compared to ACCF, blood loss was
significantly less in patients that underwent ACDF (OR = -528.63, 95% CI:
-586.86, -470.39; _p_ < 0.00001). Operative time was comparable between the
two surgical groups. Limitations were due to the low-quality of the included
studies (all studies were retrospective observational cohorts or case-control
designs) and indirectness (11 of the studies were conducted in Asia [China,
South Korea]).

Xu, et al. (2017) pooled data from 6 NRSI (379 patients) in comparing ACDF
with posterior laminoplasty (LAMP).43 No significant differences between the
two surgical groups were found for operative time (MD = 32.81, 95% CI = -26.76
to 92.38; _p_ = 0.28) and blood loss MD = -24.16, 95% CI = -174.47 to 126.15;
_p_ = 0.75). Limitations included the low-quality study designs (All studies
were retrospective observational cohorts or case-control), indirectness (all
studies had mean ages between 44.7 and 67 years), imprecision (data were
derived from small studies with wide confidence intervals that crossed the
indicator for no effect), and inconsistency (very high unexplained
heterogeneity).

A systematic review with meta-analysis of 669 participants (4 NRSI) assessed
surgical outcomes between ACDF and hybrid surgery.44 Blood loss significantly
favored ACDF over hybrid surgery (SMD = -30.29, 95% CI = -45.06, -15.52; _p_
<.00001), while operative time was similar. The limitations of this review
involved the low-quality study designs (all studies were retrospective
observational cohorts or case-control designs), and indirectness (none of the
studies were performed in the United States, and the mean age among studies
ranged from 46.1 to 54.36 years).

Primary Studies

One RCT that was not included in any evidence synthesis was identified. El-
Ghandour, et al. (2020) compared ACDF with posterior laminectomy with or
without fusion in the management of degenerative cervical myelopathy (DCM).42
Sixty-eight patients (mean age 53 years) were enrolled in the 1:1 randomized
trial. The mean operative duration was significantly longer in the ACDF group
(p < 0.001). The mean hospital stay was significantly longer in the posterior
group (p < 0.001). The authors noted several methodologic limitations
including a high risk of bias in the randomization process, small sample size,
and short-term follow-up.

Overall, the observed perioperative results varied by the comparators and the
type of outcome. Compared to open PCF, ACDF had significantly longer operative
time and LOS. MI-PCF also had a significantly less LOS than ACDF. When ACDF
was compared to other surgical techniques, no significant differences were
found in operative time and blood loss. The overall certainty of the evidence
was rated as very low due to the high risk of bias in the included RCTs,
limitations inherent in observational studies, and uncertainty about the
applicability of the results to the U.S. Medicare population (indirectness).

**_Radiographic Outcomes_**

Five evidence syntheses included assessments of radiographic outcomes (fusion
rate, range of motion [ROM], alignment, and lordotic.36,37,39,40

Fusion rate was recorded in a systematic review with meta-analysis of 18
primary studies (1 RCT, 17 NRSI).36 After a minimum of 6 months post-surgery,
the authors found the fusion rate was 100% for patients that underwent ACDF
and ACCF. Review limitations involved the low-quality of selected studies (17
of 18 studies were of observational designs), indirectness (17 of 18 studies
included participants located in China or South Korea, and all the studies had
a mean/median between 32-59 years), imprecision (all studies had small sample
sizes with confidence intervals that crossed the indicator for no effect), and
inconsistency (there was significant heterogeneity for all secondary outcomes
except fusion rate).

In another systematic review with meta-analysis, Han, et al. (2014) also
reported no difference in fusion rates between ACDF and ACCF (OR = 1.17, 95%
CI = 0.34 to 4.11; _p_ = 0.80).37 Cobb and segmental angles were measured at a
minimum of 24 months follow-up. ACDF showed statistically significant outcomes
compared to ACCF. The limitations in this review included the low-quality of
the selected studies (all studies were observational cohort or case-control
designs), indirectness (mean ages ranged from 44-58.74 years), imprecision
(all studies had small sample sizes), and inconsistency (high statistical
heterogeneity was present for fusion rate and Cobb angle).

Montano, et al. (2019) conducted a systematic review with meta-analysis that
compared radiographic outcomes reported in 5 NRSI between ACDF and
laminoplasty.39 The Cobb angle (cervical lordosis) results were significantly
better for the ACDF group (MD = 5.63; 95% CI, 1.663-8.469; _p_ = 0.004), while
ROM favored laminoplasty (MD = -5.399; 95% CI, -10.584 to -0.214; _p_ =
0.041). Limitations included the low-quality of analyzed studies (all were
observational cohort or case-control designs), indirectness (all studies had
mean ages between 54 and 56.8 years) imprecision (too few events for all
outcomes and wide confidence intervals for all pooled outcomes measured), and
inconsistency (high heterogeneity involving cervical lordosis and ROM.

A systematic review with meta-analysis of 14 NRSI (5,249 patients diagnosed
with multilevel CSM) reported statistically significant results favoring ACDF
versus ACCF in sagittal and segmental angles, as well as fusion rate.40
Limitations were due to the low-quality of the included studies (all studies
were retrospective observational cohorts or case-control designs) and
indirectness (11 of the studies were conducted in Asia [China, South Korea]).

Zhao, et al. (2018) evaluated the radiographic effects of ACDF compared to
hybrid surgery.44 The meta-analysis of 669 patients (4 NRSI) found no
significant differences in fusion rate and C2-C7 (Cobb) angle at 24 to 38
months post-surgery. Review limitations included the low-quality of the
selected studies (all were retrospective observational cohorts or case-control
designs), indirectness (none of the studies were performed in the United
States and the mean age among studies ranged from 46.1 to 54.36 years),
imprecision (wide confidence angles that represented variable outcomes were
found in the pooled data fusion rate), and inconsistency (heterogeneity of
effects in the pooled analyses for C2-C7 angle and fusion rate).

In aggregate, radiographic outcomes - obtained at variable time points -
showed equitable or favorable results in fusion rate, angular measurements,
and alignment for ACDF compared to ACCF, laminoplasty, and hybrid surgery.
Laminoplasty was superior to ACDF in preserving ROM. The certainty of the
evidence was determined to be very low due to the types of included study
designs (mostly retrospective NRSI), uncertainty about the generalizability to
the U.S. Medicare population, imprecise results, and heterogeneity of
findings.

**_Undesirable Effects_**

Six evidence syntheses provided findings regarding a range of undesirable
effects associated with cervical fusion surgeries.36-40,44 Four reviews
focused on the total or overall complication rate.36-39 In addition to the
total complication rate, two syntheses detailed the results of a range of
undesirable effects.40,44

Fei, et al. (2015) reported that the total complication rate was significantly
lower for individuals with ACDF than ACCF (RR= 0.51, 95% CI: 0.33, 0.80; p =
0.003).36 This result was based on a meta-analysis of 1,246 patients, with a
minimum of 6 months follow-up. Limitation of this evidence synthesis were the
low-quality of the selected studies (17 of 18 studies were of observational
designs), indirectness (17 of 18 studies included participants located in
China or South Korea, and all the studies had a mean/median between 32-59
years), imprecision (all studies had small sample sizes with confidence
intervals that crossed the indicator for no effect), and significant
heterogeneity was present.

Another systematic review with meta-analysis of 1,372 patients diagnosed with
multilevel CSM also determined the incidence of overall complications was
significantly greater in the ACCF group compared to those who had ACDF surgery
(OR = 0.50, 95% CI = 0.35 to 0.73; _p_ = 0.0003).37 In this review the minimum
follow-up period was 24 months. Limitations involved the low-quality of all
included studies (observational cohort or case-control designs), indirectness
(mean ages ranged from 44-58.74 years), and imprecision (all studies had small
sample sizes)

A network meta-analysis calculated both direct and indirect comparisons of
overall complications for patients who had undergone ACDF, ACCF, CDA, or
hybrid surgery.38 At a post-operative mean of 33.3 months, CDA resulted in a
lower incidence of complications than different types of cervical fusion
procedures. The limitations of this network meta-analysis included the low-
quality of most study designs (12 of 16 studies were case-control designs),
indirectness (indirect comparisons were a core component of the methodology,
and only a single study included a U.S. population), and imprecision (all
studies had small sample sizes).

A systematic review with meta-analysis included 5 NRSI (N=487) that compared
outcomes (mean 35.4 months) between ACDF and laminoplasty.39 There was no
statistically significant difference regarding the complication rate (OR =
1.604; 95% CI, 0.972-2.648; _p_ = 0.065). Limitations included the low-quality
of the selected studies (all included studies were observational cohort or
case-control designs), indirectness (all studies had mean ages between 54 and
56.8 years), and imprecision (wide confidence intervals for all pooled data).

Wang, et al. (2022) included data from 5,249 participants (14 NRSI) in a
systematic review with meta-analysis.40 The number of total complications was
significantly less for individuals that received ACDF compared to ACCF
(OR=0.56, 95% CI: 0.48-0.65; p < 0.00001). This study provided additional
details about specific undesired effects. No significant difference between
ACDF and ACCF was found for dysphagia, hoarseness, cerebrospinal fluid (CSF)
leakage, infection rate, epidural hematoma, axial pain, hardware breakage, and
pseudoarthrosis. ACDF demonstrated statistically superior outcomes regarding
the event rate of C5 palsy, revision surgeries, graft subsidence, and graft
dislodgement. The limitations of this review were related to the low-quality
of all the selected studies (retrospective observational cohorts or case-
control designs), and indirectness (11 of the studies were conducted in China
or South Korea).

Zhao, et al. (2018) compared ACDF to hybrid surgery, pooling data from 4 NRSI
that comprised 669 patients.44 Post-surgical outcomes were captured between 24
and 38 months. There was a significant difference in total complications
favoring ACDF (OR = 0.66, 95% CI = 0.44-0.98; P = .04). At the discrete
outcome level, there was no significant difference between ACDF and hybrid
surgery seen for graft subsidence, C5 palsy, infection, CSF leakage,
dysphagia, or epidural hematoma. Limitations related to the low-quality of all
the selected studies (retrospective observational cohorts or case-control
designs), and indirectness (none of the studies were performed in the United
States, and mean age among studies ranged from 46.1 and 54.36 years), and
imprecision (wide confidence intervals, representative of variable outcomes,
were found in the pooled data subgroup analyses for graft subsidence,
infection rate, and CSF leakage).

Primary Studies

One RCT that was not included in any evidence synthesis was identified. El-
Ghandour, et al (2020) compared ACDF with posterior laminectomy with or
without fusion in the management of degenerative cervical myelopathy (DCM).42
Sixty-eight patients (mean age 53 years) were enrolled in the 1:1 randomized
trial. No significant difference in postoperative complications was found,
except postoperative dysphagia was significantly higher in the anterior group
(p < 0.05). The authors noted several methodologic limitations including a
high risk of bias in the randomization process, small sample size, and short-
term follow-up.

A retrospective cohort compared the short-term outcomes for laminoplasty,
laminectomy with fusion, and ACDF.45 Data from 546 patients resulted in the
authors concluding that laminectomy with fusion carries the highest risk for
morbidity, mortality, and unplanned readmissions in the short-term
postoperative period. Laminoplasty and ACDF cases carry similar short-term
complications and risks. Study limitations include the retrospective design,
short-term (30-day) outcomes, and clinical heterogeneity.

Overall, apart from CDA, the complication rate favored ACDF over other types
of fusion and non-fusion surgeries. The certainty of the evidence was judged
to be very low due to inherent study design limitations, indirectness,
imprecision involving subgroup analyses, and significant heterogeneity.

****

**Cervical Myeloradiculopathy (Mixed)**

Cervical myelopathy occurs when there is compression of the spinal cord in the
neck area. Patients present with issues with fine motor skills, pain or
stiffness in the neck and loss of balance. Causes of cervical myelopathy may
include Rheumatoid arthritis, cervical spine trauma, spinal infection, spinal
tumors or cancer.46

Myelopathy and cervical spine instability severity is classified based on the
criteria put forth by Ranawat.47,48

  * Class I - No neurologic deficit
  * Class II - Subjective weakness with hyperreflexia and dysesthesia
  * Class IIIA - Objective weakness with long-tract signs; remains ambulatory
  * Class IIIB - Objective weakness with long-tract signs; nonambulatory and quadriparetic

**_Clinical Outcomes_**

Four evidence syntheses with publication dates ranging from 2013-2022 that
assessed clinical outcomes were identified.49-52 All the syntheses included
only randomized controlled trials. The number of primary studies in the
syntheses ranged from 8 to 30, with generally small sample sizes. The
eligibility criteria included participants that were diagnosed with single or
multilevel cervical radiculopathy, myelopathy, or both (myeloradiculopathy).
All reviews compared the effects of ACDF to CDA. Timing to follow-up was
variable (29 months to ~8 years).

Nunez, et al. (2022) published a systematic review with meta-analysis that
comprised 9 RCTs with sample sizes ranging from 44 to 541.49 Clinical outcomes
were assessed at a mean of 7.8 years post-surgery. The overall success rate in
the CDA group was significantly higher than in the ACDF group (OR = 1.98, 95%
CI: 1.57-2.49, p < 0.001) with moderate heterogeneity (I2 = 36%, p = 0.16).
There were no significant differences between the 2 groups regarding neck pain
(SMD =  0.17, 95% CI:  0.37-0.04, p = 0.11) with high heterogeneity (I2 =
74%, p = 0.002). Patient-reported arm pain results significantly favored the
CDA group (SMD =  0.16, 95% CI:  0.29 to  0.04, p = 0.01) with moderate
heterogeneity (I2 = 31%, p = 0.20). The physical SF-36 (quality of life)
component significantly favored the CDA group (SMD = 0.13 95% CI: 0.03-0.23, p
= 0.01) with very low heterogeneity (I2 = 1%, p = 0.40). No significant
differences were found between the 2 groups in the mental SF-36 component (SMD
= 0.19, 95% CI:  0.03-0.41, p = 0.10), with substantial heterogeneity (I2 =
69%, p = 0.02). Limitations of this review included a high or unclear risk of
bias involving all RCTs, indirectness (the mean age across studies was ~44.5
years), some imprecision involving overall treatment success, significant
heterogeneity was present in all pooled clinical results.

Peng, et al. (2022) produced a systematic review with meta-analysis of 9,329
participants with single or multilevel cervical radiculopathy or myelopathy.
At multiple follow-up time points, overall success favored CDA (total, OR
1.91, 95% CI 1.73 to 2.11, p=0.000).50 Neurological success results also
favored CDA in all follow-up periods (total, OR 1.74, 95% CI 1.49 to 2.04, p =
0.000). Disability results in all follow-up periods favored CDA (total, OR
1.70, 95% CI 1.49 to 1.94, p = 0.000). Limitations of this analysis included
all primary studies were rated as having unclear (some concerns) or high risk
of bias, indirectness (the mean age among the studies ranged between 40-50
years), and imprecision (all pooled analyses for each follow-up period had
confidence intervals that crossed the null value).

Xing, et al. (2013) included 8 RCTs with sample sizes ranging from 19 to 541.
Participants (N=1,617) had single-level cervical radiculopathy or myelopathy
[Xing]. Outcomes were measured between 24 and 48 months. For overall success,
CDA was significantly superior to ACDF (OR = 1.84, 95% CI = 1.43 to 2.36; p <
0.00001), with no heterogeneity (I2 = 0%). The neurological success rate
results showed CDA was significantly superior to ACDF (OR = 1.75, 95% CI =
1.20 to 2.55; p = 0.004), with no heterogeneity (I2 = 0%). There was no
significant difference between the two treatment groups concerning disability
measures. For arm pain, there was a significant difference between the two
groups favoring CDA (MD = -4.86, 95% CI = -6.42 to -3.30; p < 0.00001) with
low heterogeneity (I2 = 8%). There was a significant difference between the
two groups favoring CDA (MD = -7.90, 95% CI = -10.36 to -5.44; p < 0.00001)
with no heterogeneity (I2 = 0%) regarding neck pain outcomes. Limitations of
this evidence synthesis included all primary studies were rated as having
unclear (some concerns) or high risk of bias, indirectness (the mean age of
included studies was 43 years), imprecision (six of eight [75%] of studies had
sample sizes smaller than 400 and all pooled analyses exhibited confidence
intervals that crossed the null value), and inconsistency (moderate
heterogeneity in the pooled results for disability).

Zhang, et al. (2020) included 1,238 participants from 13 RCTs in a systematic
review with meta-analysis.52 Outcomes were assessed at a mean of 83 months.
The overall success rate significantly favored the CDA group compared to the
ACDF group (OR = 1.68, 95% CI: 1.29-2.19, p < 0.001) with low heterogeneity
(I2 = 0%, p = 0.62). The CDA group had significantly higher neurological
success than the ACDF group (OR = 1.54, 95% confidence interval [CI]: 1.14-
2.08, p = 0.004) with moderate heterogeneity (I2 = 34.0%, p = 0.18). For
disability results, the CDA group was significantly improved versus the ACDF
group (MD =  0.20, 95% CI:  0.36 to  0.05, p = 0.009), with moderate
heterogeneity (I2 = 37.8%, p = 0.20); however, the effect size did not reach
clinical relevance. Measures of quality-of-life were better in the CDA group;
however, neither statistical nor clinical significance was achieved. Both neck
and arm pain were significantly better in the CDA group than in the ACDF
group (MD =  0.20, 95% CI:  0.35 to  0.05, p = 0.01 and MD =  0.23, 95%
CI:  0.38 to  0.07, p = 0.004, respectively), with low heterogeneity (I2 =
31.6%, p = 0.23 and I2 = 24.3%, p = 0.27, respectively). Limitations of this
evidence synthesis included studies were rated as having unclear (some
concerns) or high risk of bias, indirectness (the mean age across studies was
~44.5 years), imprecision (confidence intervals crossed the null effect), and
inconsistency (moderate to substantial heterogeneity was found in the pooled
analyses for neurological success and disability outcomes).

In aggregate, CDA demonstrated statistically significant improvement across
clinical outcomes apart from quality-of-life measures, which were similar to
ACDF. The clinical significance of the results was not described when
assessing most pooled results for specific outcomes. Overall, the certainty of
evidence was judged to be very low. All the included RCTs were rated as having
unclear (some concerns) or a high risk of bias. The mean age among the studies
ranged between 40-50 years and clinical relevance was not usually assessed
(indirectness). More than 50% of studies had small sample sizes and wide
confidence intervals suggesting variable effects (imprecision).

**_Surgical Outcomes_**

A single evidence synthesis provided data regarding surgical results.

Peng, et al. (2022) conducted a systematic review with meta-analysis of 30
RCTs.50 Participants (N=9,329) with single or multilevel cervical
radiculopathy or myelopathy randomly underwent ACDF or CDA. The pooled data
showed ACDF had a significantly longer operative duration (OR,  0.28; 95% CI,
 0.37 to  0.2; p = 0.000). There were no significant differences between CDA
and ACDF for blood loss and LOS (OR, 0.63; 95% CI,  2.83 to 4.1; p = 0.72;
OR,  0.01; 95% CI,  0.08 to 0.05; p = 0.68, respectively). The limitations
of this analysis included all primary studies were rated as having unclear
(some concerns) or high risk of bias, indirectness (the mean age among the
studies ranged between 40-50 years), and imprecision (all pooled analyses for
each follow-up period had confidence intervals that crossed the null value).

Based on limited data, CDA demonstrated more than a 25% reduction in operative
time compared to ACDF. There were no other perioperative outcomes that
revealed significant differences between CDA and ACDF. The certainty of the
evidence was rated as very low. All included primary studies had unclear (some
concerns) or a high risk of bias. There was uncertainty about the
applicability of the results to the U.S. Medicare population (indirectness).
All pooled analyses for each follow-up period had confidence intervals that
crossed the null value (imprecision).

**_Radiographic Outcomes_**

Three evidence syntheses reported on radiographic results in comparing ACDF
with CDA.49,51,52

Nunez, et al. (2022) systematically reviewed and meta-analyzed data from 9
RCTs (N=2,664) who received either ACDF or CDA.49 The fusion rate was 94.06%
in the ACDF group, with no data for CDA. The heterotopic ossification rate for
CDA = 10.3%, with no data for ACDF. The ROM rate in the CDA group was
significantly higher (SMD = 1.86, 95% CI: 1.63-2.08, p < 0.001) with no
heterogeneity (I2 = 0%, p = 0.52). Less superior adjacent segment disease
(ASD) was reported in the CDA group (OR = 0.33, 95% CI: 0.17-0.65, p = 0.001)
with substantial heterogeneity (I2 = 81%, p < 0.001). Less inferior ASD was
reported in the CDA group (OR = 0.31, 95% CI: 0.15-0.66, p = 0.002), with
substantial heterogeneity (I2 = 75.1%, p = 0.05). Limitations of this review
included a high or unclear risk of bias involving all RCTs, indirectness (the
mean age across studies was ~44.5 years), and inconsistency (significant
heterogeneity was present in all pooled results except ROM).

Xing, et al. (2013) measured radiological success as part of a systematic
review with meta-analysis.51 There was no significant difference between the
ACDF and CDA groups (OR = 0.87, 95% CI = 0.36 to 2.09; _p_ = 0.76).
Limitations of this evidence synthesis included all primary studies were rated
as having unclear (some concerns) or high risk of bias, indirectness (the mean
age of included studies was 43 years), and imprecision (six of eight {75%} of
studies had sample sizes smaller than 400 and all pooled analyses exhibited
confidence intervals that crossed the null value).

Zhang, et al. (2020) pooled data from 13 RCTs (N=1,238) in assessing ROM
between patients who had ACDF or CDA.52 The CDA group had significantly larger
ROM than the ACDF group (MD = 1.76, 95% CI: 1.57- 1.94, p < 0.001) with low
heterogeneity (I2 = 0%, p = 0.38). Limitations of this evidence synthesis
included all studies having unclear (some concerns) or high risk of bias,
indirectness (the mean age across studies was ~44.5 years), imprecision
(confidence intervals crossed the null effect), and inconsistency (moderate
heterogeneity regarding ASD outcomes).

Overall, apart from overall success, CDA demonstrated statistically greater
radiological results when compared to ACDF. The certainty of the evidence was
determined to be very low. Limitations included high or uncertain risk of bias
across all included trials, indirectness, imprecision, and heterogeneity (ASD
outcomes).

**_Undesirable Effects_**

Four evidence syntheses reported the pooled results of undesirable effects
associated with cervical spine surgeries. All studies were conducted as
systematic reviews with meta-analysis of RCTs.49-52

Nunez, et al. (2022) described outcomes for 2,664 participants obtained from 9
RCTs.49 For overall complication rate, no significant differences were found
between CDA (33.1%) and ACDF (38.9%) (OR = 0.84, 95% CI: 0.56-1.27, _p_ =
0.42), with moderate heterogeneity ( _I_ 2 = 37%, _p_ = 0.13). (p = 0.42).
Reoperations occurred in 4.4% of CDA patients, a significantly lower rate
compared with 15.6% of the ACDF group (OR = 0.26, 95% CI: 0.19-0.37, _p_ <
0.001), with no heterogeneity ( _I_ 2 = 0.0%, _p_ = 0.97). The limitations of
this review included a high or unclear risk of bias involving all RCTs,
indirectness (the mean age across studies was ~44.5 years), and inconsistency
(significant heterogeneity was present in the pooled results).

Peng, et al. (2022) included 30 RCTs (N=9,329) in the review comparing ACDF
with CDA.50 In assessing implant events, no significant difference was found
between the CDA and ACDF groups in short-term, mid-term, and long-term follow-
up and total analysis (total, OR 1.14, 95% CI 0.92 to 1.42, p = 0.23). The
incidence of ASD was higher in the ACDF group in long-term follow-up and total
analysis (total, OR 0.71, 95% CI 0.55 to 0.94, p = 0.01). The incidence of
dysphagia and dysphonia was higher in ACDF in short-term follow-up. There were
no significant differences in total, mid- and long-term follow-up between CDA
and ACDF (total, OR 0.9, 95% CI 0.73 to 1.09, p = 0.28). The reoperation rate
was higher in ACDF in all follow-ups (total, OR 0.37, 95% CI 0.29 to 0.46, p =
0.000). This analysis had limitations including all primary studies were rated
as having unclear (some concerns) or high risk of bias, indirectness (the mean
age among the studies ranged between 40-50 years), and imprecision (all pooled
analyses for each follow-up period had confidence intervals that crossed the
null value).

Xing, et al (2013) compared the overall complication rates of ACDF and CDA for
a mixed (cervical radiculopathy or myelopathy) population.51 The meta-analysis
found there was no significant difference between the two surgical methods (RR
= 0.77, 95% CI = 0.48 to 1.23; _p_ = 0.27) with moderate heterogeneity ( _I_ 2
= 39%). Limitations of this evidence synthesis included all primary studies
were rated as having unclear (some concerns) or high risk of bias,
indirectness (the mean age of included studies was 43 years), and imprecision
(six of eight {75%} of studies had sample sizes smaller than 400 and all
pooled analyses exhibited confidence intervals that crossed the null value).

Zhang, et al. (2020) provided a comprehensive meta-analysis of undesired
effects for 1,238 participants who underwent ACDF or CDA.52 The difference in
complication rates was not significant between the two groups (OR = 1.01, 95%
CI: 0.77-1.32, p = 0.96), with low heterogeneity (I2 = 8.4%, p = 0.37). For
reoperations at the index level, the rate was significantly lower in the CDA
group than in the ACDF group (OR = 0.41, 95% CI: 0.25-0.69, p = 0.001), with
substantial heterogeneity (I2 = 61.0%, p = 0.004). For reoperation at an
adjacent level, the rate was significantly lower in the CDA group than in the
ACDF group (OR = 0.34, 95% CI: 0.26-0.46, p < 0.001), with low heterogeneity
(I2 = 23.4%, p = 0.22). Limitations of this evidence synthesis included all
studies having unclear (some concerns) or high risk of bias, indirectness (the
mean age across studies was ~44.5 years), imprecision (confidence intervals
crossed the null effect), and inconsistency (substantial heterogeneity
regarding the reoperation rate).

In aggregate, ACDF and CDA demonstrate similar overall complication rates;
however, CDA resulted in fewer reoperations and less ASD. ACDF and CDA result
in equitable long-term dysphagia and dysphonia outcomes. The overall certainty
of the evidence was determined to be very low due to the high or unclear risk
of bias in the included RCTs, indirectness, imprecise results, and
inconsistency (heterogeneity) affecting multiple outcomes.

**__**

**_Societal Guidance_**

**North American Spine Society (NASS)** **3** appropriateness criteria for
cervical fusion surgery as a treatment for cervical myelopathy states "While
there are some non-fusion procedures available to decompress the spinal canal
such as laminoplasty and anterior cervical discectomy without fusion, the
workhorses of surgical treatments for cervical spondylotic myelopathy (CSM)
are ACDF, anterior corpectomy and fusion, and posterior laminectomy and
fusion. It is well-accepted that non-operative care is acceptable in patients
with mild myelopathy and that surgery should be considered in most. Anterior
cervical decompression and fusion has become the most common surgical approach
and technique for treating patients with CSM. With the availability of modern
posterior cervical screw fixation, posterior cervical laminectomy and fusion
has become an additional workhorse for treatment of CSM, with equivalent
results as anterior surgery."

Cervical myelopathy: (either from disc herniation, bony stenosis, or
ossification of posterior longitudinal ligament [OPLL]) may be considered as
an adjunct to decompression when anterior cervical discectomy, corpectomy or
posterior laminectomy is planned for decompression of the spinal cord.

**A multidisciplinary expert panel** defined appropriate use criteria (AUC) of
cervical fusion for the treatment of degenerative conditions of the cervical
spine [Reitman]. Appropriate use criteria were developed using the RAND/UCLA
appropriateness methodology. All scenarios included a surgical plan as either
cervical fusion (nonspecific) or specified as anterior cervical fusion (ACF),
posterior cervical fusion (PCF), or combined (APCF). Clinical scenarios
involving myelopathy was most strongly associated with an "Appropriate"
rating. A total of 92% of scenarios with myelopathy, and well controlled
medical or mild psychosocial comorbidities, or smokers, received a final
rating of "Appropriate." All (100%) scenarios with myelopathy and poorly
controlled medical or mild psychosocial comorbidities, or smokers, received a
final rating of "Appropriate" for cervical fusion surgery.

**AOSpine North America and the Cervical Spine Research Society** **53**
published clinical practice guidelines that outline recommendations about how
to best manage (1) patients with mild, moderate, and severe myelopathy and (2)
nonmyelopathic patients with evidence of cord compression with or without
clinical symptoms of radiculopathy.

Recommendations based on 5 systematic reviews of the literature concerning the
value of surgery and nonsurgical approaches for CSM were as follows: (1) "We
recommend surgical intervention for patients with moderate and severe DCM."
(2) "We suggest offering surgical intervention or a supervised trial of
structured rehabilitation for patients with mild DCM. If initial nonoperative
management is pursued, we recommend operative intervention if there is
neurological deterioration and suggest operative intervention if the patient
fails to improve." (3) "We suggest not offering prophylactic surgery for
nonmyelopathic patients with evidence of cervical cord compression without
signs or symptoms of radiculopathy. We suggest that these patients be
counseled as to potential risks of progression, educated about relevant signs
and symptoms of myelopathy, and be followed clinically." (4) "Non-myelopathic
patients with cord compression and clinical evidence of radiculopathy with or
without electrophysiological confirmation are at a higher risk of developing
myelopathy and should be counseled about this risk. We suggest offering either
surgical intervention or nonoperative treatment consisting of close serial
follow-up or a supervised trial of structured rehabilitation. In the event of
myelopathic development, the patient should be managed according to the
recommendations above."

**The World Federation of Neurosurgical Societies (WFNS) The Spine Committee
of the World Federation of Neurosurgical Societies (WFNS)** formulated an
evidence-based consensus meeting on the management of CSM to develop
recommendations for global applicability.54 With some adaptations, the WFNS
Spine Committee endorsed the guidelines of AOSpine North America and the
Cervical Spine Research Society.53 Additional recommendations include: using
mJOA or its regional modifications to classify CSM as severe, moderate or mild
and suggest offering surgical intervention or rehabilitation for patients with
mild CSM (modified Japanese Orthopedic Association scale [mJOA] score 15-17\.
They state there is a consistent lack of evidence regarding the value of
nonoperative treatment of cervical myelopathy in the literature hence
nonoperative treatment may not be the final decision in most cases. They also
share that predicting factors that indicate a possible deterioration during
nonoperative, important predictors of myelopathy development include the
presence of symptomatic radiculopathy, prolonged motor evoked potentials and
somatosensory evoked potentials and electromyography signs of anterior horn
cell lesions (low evidence), patients are likely to achieve a better result
after surgery if they have a shorter duration of symptoms (low evidence) and a
call for additional RCTs.

**World Federation of Neurosurgical Societies (WFNS) Spine Committee**
recommendations include:

  * In patients with CSM, the indications for surgery include persistent or recurrent radiculopathy nonresponsive to conservative treatment (3 years); progressive neurological deficit; static neurological deficit with severe radicular pain when associated with confirmatory imaging (computed tomography, magnetic resonance imaging) and clinical-radiological correlation.
  * The indications of anterior surgery for patients with CSM include straightened spine or kyphotic spine with a compression level below.

They clarify in the elderly age groups with bony ankylosis due to osteophytes
at C5-6-7, CSM may manifest at higher levels where motion segments are
preserved, especially the C3-4 level and also at lower levels such as the
C7-T1 level. These guidelines provide directives for future research with
suggested outcome measures, variabilities to consider as well as patient and
surgery selection guidance.

**The Italian Neurosurgical Society (SINch)** **55** analyzed and proposed
their own recommendations for the management of CSM in accordance with the
recommendations published by the spine committee of the WFNS. The majority of
WFNS recommendations were adopted with a few modifications.

**The Japanese Orthopaedic Association (JOA)** published 2023 clinical
practice guidelines on the management of cervical spondylotic
myelopathy(CSM).56 The recommendations relevant to this evidence analysis are
reported here:

  * For mild cases of CSM, conservative treatment is primarily selected; however, at present there is insufficient evidence regarding treatment outcomes. Surgery is considered suitable for progressive myelopathy in which conservative treatment is unsuccessful.
  * It is possible that conservative treatment can delay the progression of mild-to-moderate   
CSM, and therefore, performing conservative treatment is weakly recommended.
For severe and progressive CSM, surgery is likely the first choice of
treatment. However, there are few reports regarding the choice of treatment
for mild and moderate CSM, and thus, it is difficult to draw a conclusion.

  * There is no clear recommendation regarding which surgeries to perform

**Additional Systematic Review/Meta-Analysis**

Youssef57 et al. conducted a systematic review and meta-analysis to evaluate
the patient-reported and clinical outcomes of adult patients who underwent
subaxial posterior cervical fusion with decompression for spondylosis, spinal
stenosis and degenerative disc disease resulting in radiculopathy or
myelopathy. PubMed and Embase were searched for applicable literature
resulting in a total of 33 and 31 articles which included in the systematic
review and the meta-analysis, respectively. Changes in values of preoperative
to postoperative patient-reported outcomes (visual analog scales for arm pain
and neck pain, Neck Disability Index (NDI), JOA score, modified JOA score, and
Nurick pain scale) were evaluated. Patient reported outcomes, successful
fusion, revision surgeries, and complications/adverse events were considered.
A subgroup analysis was performed in two instances; one for studies that
included surgical indications for only myelopathy or radiculopathy (or
combination) and another for studies that included surgical indications for
only myelopathy or ossifications of the posterior longitudinal ligament (or
combination). Cumulative changes in PROMs improved for all surgical
indications including the two subgroup analyses. All surgical indications
resulted in pooled outcomes rates of 98.25% for successful fusion, 1.09% for
revision, and 9.02% for complications/adverse events. Axial pain, C5 palsy,
transient neurological worsening, and wound infection were the most common
complications. Limitations include high risk of bias, reporting bias,
confounding, high heterogeneity, included 20/31 retrospective studies, and
combining of different PROMs. Authors report many conflicts of interest but
none that seem to impact this study; however, the study was funded by
Providence Medical Technology, Inc.

**_Unstable Spine_**

**Systematic Review/Meta-Analysis** Mahmoud58 and colleagues conducted a
systematic review comprised of 627 patients and 36 articles to review the
surgical indications, complications, and functional outcomes of different
approaches for hangman fractures. Selected literature contained at least one
of the primary outcomes: functional outcomes, complication rates, operation
time, and blood loss. Minimally invasive surgery, C2 direct pedicle screw, C2-
C3 fusion, and ACDF techniques were reviewed. VAS scores fell in all four
groups when comparing pre- and postoperative scores, with the lowest VAS
scores observed in the minimally invasive surgery group. In unstable fracture
patterns, the literature showed that ACDF was preferred. Complications
remained low in all groups with the greatest blood loss occurring in the
posterior approach (255.9 mL in open posterior approach, 75.8 mL in MIS, and
64.3 mL in ACDF). Authors concluded if indicated, posterior approach may be
preferred due to lower blood loss and disc access. When considering posterior
approach, MIS may improve outcomes and have fewer complications. Limitations
of the present study are inclusion of studies with retrospective study design,
variations in reporting methods making data points challenging to categorize
and lack comparative outcome studies.

Lee59 and associates performed a meta-analysis comparing biomechanical and
clinical outcomes between anterior-only and combined anterior and posterior
fusions to determine which method of cervical fusion yielded better results
for unstable cervical injuries. Ultimately, the analysis included 12 studies
(eight biomechanical and four clinical studies) which included published dates
between 2000-2019. Authors concluded cervical stability can be successfully
restored following subaxial cervical injuries by anterior-only and combined
anterior and posterior methods. No significant differences in clinical
outcomes were observed while some advantages were associated with combined
fusion in terms of biomechanical stability. Selective use of methods should be
determined based on type of injury. Authors also note need for control of
technical factors of surgery that may have impacted results of cervical
fusion. Limitations include a small sample size, in vitro studies, low number
of studies included for analysis, and risk of bias.

**Prospective**

Yang60 et al. performed a prospective study to propose a novel classification
and scoring system called the posterior ligament-bone injury classification
and severity score (PLICS) that offers a quantitative score to guide the need
for posterior stabilization in addition to anterior reconstruction for
subaxial cervical fracture dislocations (SCFDs). The study included 456 SCFD
patients. High risk patients were defined as having PLICS  7 together with
extremely unstable lateral mass fracture (EULMF). All others were defined as
low-risk patients. Anterior only reconstruction was performed in the low-risk
patients and additional posterior lateral mass fixation and fusion was
performed after anterior reconstruction in the high-risk patients. The visual
analogue score (VAS), the NDI, the American Spinal Injury Association (ASIA)
impairment scale were utilized for outcomes. At 12 month follow up, 321
patients in the low-risk group and 49 patients in thehigh-risk group were
still participating. VAS scores from preoperative to 12 months significantly
improved (from 6.1 + 0.3 to 1.1 + 0.2 in the low-risk group, P < 0.001; from
6.4 + 0.2 to 1.4 + 0.2 in the high-risk group, P < 0.001). In the low-risk
group at 12 month follow up the average NDI score was statistically low 8.8 +
2.5 vs 13.8 + 3.4, P = 0.034). With regards to the ASIA scale, 80.5% of
patients experienced _>_ 1 grade improvement. Authors concluded for SCFD
patients, EULMF and a PLICS score of 7 or greater may serve as a threshold for
posterior stabilization in addition to anterior reconstruction. Limitations
include the study design, patient selection methods, and exclusion of
ankylosing spondylitis (AS) patients.

Madan61 et al. conducted a prospective cohort study to assess the functional,
neurological, and radiological outcomes of the patients with traumatic
cervical spine instability. A total of 99 patients with subaxial cervical
spine injuries were admitted and operated on at a single center between
February 2014 and February 2016 and included prospectively. In all patients,
bony fusion, neurological recovery, NDI and complications were assessed during
the mean follow up period of 27 months (range 12-42 months). Corpectomy
procedures that involved 1 level were 77.8% (n=77), 2 levels were 19.2% (n=19)
and 3 levels were 3% (n=3). Neck Disability Index resulted in a mean of 7.57 
5.42. Grade 1 fusion was reported in 64.6% of cases. The most frequent adverse
event was dysphagia 79.8% (n=79). Authors concluded an appropriate treatment
option for subaxial cervical spine injuries is anterior cervical corpectomy
and stabilization with cage filled with bone and cervical reflex locking
plate. Authors further state this procedure is associated with favorable
fusion rates and is likely a procedure of choice for posttraumatic multiple
disc prolapse. Limitations of this study include study design, single center
inclusion, risk of bias and sample size.

**Retrospective**

Zheng62 and associates conducted a single center, retrospective, observational
study comprised of 79 patients to investigate the role of ACDF in alleviating
symptoms in patients with cervical vertigo associated with cervical
instability. A significant relief of vertigo and dizziness was reported
following anterior cervical surgery during the 2 year follow up period.

Yang63 and associates performed a retrospective chart review to investigate
the efficacy and safety of halo vest application before and during surgery in
25 patients with AS and severe thoracic kyphosis who underwent surgical
treatment of cervical fracture-dislocation. Posterior or combined anterior-
posterior surgery was performed on all patients. Authors conclude that use of
the halo vest before and during the surgery is safe and effective while
assisting with positioning, awake nasoendotracheal intubation, nursing, and
the procedure by providing satisfactory reduction and immobilization.

Wang64 et al. performed a retrospective chart review comprised of 36 patients
to investigate the safety and efficacy of the halo-vest in the treatment of
cervical fracture in patients with ankylosing spondylitis (AS) and kyphosis.
Authors concluded The AS patient should undergo early surgical stabilization
utilizing a halo-vest to aid in spinal deformity correction and to avoid
neurological decline.

Skeppholm65 and associates conducted a cohort study of 28 patients with
artificial disc replacement (ADR) or anterior cervical decompression which
were recruited from a larger RCT cohort to evaluate in vivo motion and
stability of implanted artificial discs. Authors concluded most of the ADRs
resulted in favorable mobility and proper attachment years after implantation
with instability detected in only 8% of patients.

Rustagi66 and colleagues conducted a retrospective chart review of 29 patients
to present a series of posterior-only operated occiput-cervical fixation (OCF)
cases following metastasis to the upper cervical spine (UCS) and
craniocervical junction (CCJ). Authors concluded posterior OCF without tumor
resection and anterior reconstruction can effectively manage symptomatic
metastasis while offering pain relief and improved quality of life.

Luksanapruksa67 and associates conducted a retrospective cohort study of 33
patients to evaluate surgical outcomes and complications of cervical spine
fractures in ankylosing spondylitis (CAS) patients who were treated using
either the posterior (P) or combined approach after experiencing neck pain
after a fall. Authors conclude, although not statistically significant,
posterior surgery was associated with lower blood loss, rate of complications,
and shorter length of stay as compared to the combined approach. Limitations
include study design, small sample size, and moderate lost to follow up rate.

Li68 et al. conducted a retrospective study comprised of 38 consecutive
patients to describe the authors' method of anterior discectomy/corpectomy and
fusion combined with internal fixation for the treatment of unstable hangman's
fractures and to evaluate the clinical and radiological outcomes. Authors
conclude study results indicate to address unstable hangman's fractures, an
anterior discectomy/corpectomy and fusion combined with internal fixation is a
favorable approach.

Lee69 and associates conducted a retrospective review of radiologic images of
patients (n=34) who underwent C1-2 fusion. Patients were divided into one of
two groups (the C-arm group or O-arm group). Authors concluded in cases of
unstable C1-2 pathologies posterior fixation can reduce the operative time by
utilizing intraoperative cone-beam CT scans for spinal navigation.

Lang70 and colleagues conducted a cohort study comprised of 33 patients to
assess the radiological and mid-term patient-reported outcome of traumatic
subaxial cervical fractures treated with different plate systems. Authors
concluded regarding a fragile fracture, that dynamic plate provided adequate
stability with no significant loss of reduction when compared to the rigid
plates. Patient-reported outcome were satisfactory in both groups.

Kong71 and associates retrospectively analyzed clinical data of 46 patients
who underwent C2-3 ACDF combined with internal fixation for unstable hangman's
fractures to investigate the changes in the sagittal parameters of the
cervical spine and the clinical efficacy of C2-3 ACDF combined with internal
fixation. Authors conclude that anterior reconstruction of the anterior and
middle columns with plate internal fixation can successfully achieve
stability, correct displacement and angulation of C2, and restore sagittal
balance while maintaining a high rate of fusion with few complications.

Kim72 and colleagues conducted a retrospective analysis of 65 patients who
were treated for a C1 fracture at single site between 1999 and 2016. Authors
concluded type 3 fractures are most likely to be unstable while type 2
fracture and MVC are associated with higher rates of fusion failure. Most
fractures were managed conservatively.

Bakhsheshian73 systematic case review comprised of eight cases series and 64
patients was performed to evaluate studies that utilized C2 lag screw
placement in patients with traumatic spondylolisthesis of the axis (TSA).
Authors concluded while freehand placement of C2 pedicle lag screws may be a
reasonable option in some cases, C2 lag screw fixation resulted in positive
fusion in most TSA patients. However, this study does not demonstrate
superiority over conservative treatment or other surgical methodologies and
evidence is limited to level IV studies.

Jin74 et al. conducted a retrospective clinical study to assess clinical
outcomes and sagittal balance after unstable hangman fracture in 45 patients.
Authors concluded that both anterior and posterior approaches are effective in
treating unstable hangman fractures. They further state recovery of cervical
sagittal balance was achieved by utilizing the posterior approach as compared
to the anterior approach.

Garrido75 and colleagues conducted a retrospective data review of 71 cases to
assess the clinical outcomes of both rigid and nonrigid occipitocervical (OC)
fusion constructs of a multicenter cervical spine study group. Authors
conclude a statistically significant decrease in complication rates are
associated with rigid occipitocervical construct as compared to nonrigidly
fixed.

Dagtekin76 et al. conducted a single center retrospective study comprised of
88 patients were included to evaluate OCJ injuries and to discuss the
treatment modalities of these traumas and examine cadaveric studies for a
better understanding. Authors concluded while it is essential to consider
fracture pathophysiology and fracture type, they believe the most appropriate
modality for atlantoaxial stabilization is C1-C2 segmental stabilization.

Clark77 et al. conducted a retrospective chart review comprised of 43
consecutive patients to evaluate 30-day and 1-year mortality rates and review
complications associated with posterior C1-2 fusion in an octogenarian cohort.
Authors conclude in the octogenarian population a greater mortality rate is
associated with Initial fracture displacement. Lower mortality rates resulted
with posterior C1-2 fusions with unstable type II odontoid fractures as
compared to nonoperative management mortality rates.

Candura78 et al. performed a retrospective case series on 64 consecutive
patients with Type II odontoid fractures. who presented to the Vertebral
Surgery Unit. Authors conclude odontoid Type II fractures can be successfully
treated with conservative treatment modalities in elderly patients.

Aldrian79 et al. conducted a retrospective chart review on 46 patients to
evaluate outcomes following surgical or nonoperative treatment of Hadley type
IIA odontoid fractures. Authors conclude following nonoperative management,
Hadley type IIA odontoid fractures are associated with increased risk for
secondary loss of reduction and bony nonunion.

**Surgical Approach**

Multiple studies have compared surgical approaches and have not demonstrates
superiority of one approach over another. A RCT compared ventral to dorsal
surgical approach for CSM and found among 163 subjects the approaches shared
similar outcomes at one year.80 Other studies report similar results with some
advantages and disadvantages found for each approach. A meta-analysis reports
on 4,348 subjects and concludes that laminectomy and fusion techniques offer
comparable clinical outcomes.81 A 2023 systematic review and meta-analysis
also found no significant difference in functional outcomes from ACDF vs.
posterior discectomy (PD) with moderate evidence per GRADE analysis.82 The
subject matter experts summarize that an individualized approach should be
tailored to the individual patient's pathology to determine the optimal
surgical route.

A 2023 systematic review on cervical degenerative disease treatment by the
Agency for Healthcare Research and Quality83 included 57 RCTs, 56
nonrandomized studies and one systematic review that enrolled patients with
radiculopathy and/or myelopathy at one or more levels and analyzed various
surgical approaches used. They report there were few comparative studies of
non-operative treatments, and most studies were rated moderate risk of bias
with most evidence rated lower insufficient strength to draw conclusions on
comparative benefits and harms. They included ACDF, anterior versus posterior
approach, standalone cage versus plate and cage in ACDF, and laminoplasty
versus laminotomy with fusion. They conclude there were few differences in
benefits between surgical approaches and techniques for the treatment of
cervical degenerative disease however there was some differences in the
frequency of adverse events for some comparison.

The Washington State Dept. of Labor & Industries' Industrial Insurance Medical
Advisory Committee (IIMAC) published a "Guideline for Diagnosis and Treatment
of Cervical Radiculopathy and Myelopathy" Labor & Industries84 and states:
"The ideal surgical approach for radiculopathy related to herniated disc
remains a matter of debate. Various studies have compared the different
surgery types and found no significant difference among them. Cervical
surgeries can be divided into 2 major approaches: anterior (with or without
fusion) and posterior. Except for hybrid surgeries, the choice of surgical
procedure is left to the discretion of the surgeon. Hybrid surgeries combine
artificial disc replacements and anterior cervical discectomy with fusion at
select vertebral bodies (adjacent or non-adjacent) in a single procedure. They
state there is insufficient evidence in medical literature to permit
conclusions on its safety and efficacy."

North American Spine Society (NASS) Evidence-Based Clinical Guidelines on the
Diagnosis and Treatment for Cervical Radiculopathy from Degenerative Disorders
agrees that there is a lack of evidence that one surgical approach is
superior. They reviewed multiple surgical approaches and found outcomes
comparable with a Grade B Recommendation.8

**Axial Neck Pain**

**_Background_**

Axial neck pain is a prevalent condition that causes significant morbidity and
productivity loss.85 Nonspecific (primary) axial neck pain is distinguished
from neck pain associated with specific causes (e.g., radiculopathy,
myelopathy, stenosis, fracture). The pain distribution is localized to the
neck and immediate surrounding structures and does not involve dysfunction of
the arms, hands, fingers, or other body regions. It is characterized primarily
by dull, achy pain in the nuchal region (posterior) neck.86 The pain can
sometimes travel to the base of the skull, shoulder, or scapulae. Other
symptoms may include neck stiffness, headaches, and localized areas of muscle
pain or paresthesia. Most axial neck pain is diagnosed based on ruling out
specific causes of neck pain. There is a wide range of pharmacologic and non-
pharmacologic treatment options for axial neck pain. The appropriateness of
surgery for axial neck pain is uncertain.87 The purpose of this analysis is to
summarize the evidence on the impact of fusion surgery procedures for the
management of primary axial neck pain.

**_Literature Analysis_**

In a systematic review with meta-analysis, van Middelkoop, et al. (2012)
identified 10 RCTs that compared additional fusion upon anterior decompression
surgical techniques. The reviewers found there was no additional benefit of
fusion techniques applied within an anterior discectomy procedure in patients
with neck pain without radiculopathy on pain, recovery, and return to work.
For recovery, the pooled risk difference in the short-term follow-up was -0.06
(95% CI -0.22 to 0.10) and -0.07 (95% CI -0.14 to 0.00) in the long-term
follow-up. The pooled risk differences for pain and return to work all
demonstrated no differences.88

Riew, et al. (2010) conducted a systematic review that examined the clinical
outcome in patients undergoing ACDF for axial neck pain without radicular or
myelopathic symptoms.89 No comparative studies were identified; however, three
case series were evaluated. All studies showed a mean improvement of pain of
at least 50% approximately 4 years following surgery. Functional outcomes
improved between 32% and 52% from baseline. Most patients reported
satisfaction with surgery, 56% in one study and 79% in another. Complications
varied among studies ranging from 1% to 10% and included pseudoarthrosis (9%),
nonunion and revision (3%), and screw removal (1%). The authors concluded,
"There is low evidence suggesting that patients with axial neck pain without
radicular or myelopathic symptoms may receive some improvement in pain and
function following ACDF. However, whether this benefit is greater than
nontreatment or other treatments cannot be determined with the present
literature." The authors reported several limitations in their review. These
included low-quality primary study designs (noncomparative case series),
indirectness (the mean age of patients ranged from 42-56 years) imprecise data
(small sample sizes, and the proportion of patients who achieved a clinically
meaningful improvement in pain and function >30% was not reported), and
inconsistency regarding the selection of fusion levels and integrity of discs
adjacent to the operated levels, and the role of provocative testing)

As part of a Neck Pain Task Force, Carragee, et al. (2008) conducted a best-
evidence synthesis of literature from 1980 through 2006 on surgical
interventions for neck pain alone in the absence of serious pathologic
disease. The reviewers found that cervical fusion for neck pain without
radiculopathy was not supported by current evidence.90 The literature search
identified 4 frequently cited studies, which were deemed to be scientifically
inadmissible, pertaining to cervical Fusion for non-radicular neck pain with
only common degenerative changes.

  * Palit, et al. (1999) retrospectively reported on the outcomes of 38 patients out of a possible 175 subjects (22%) who underwent ACDF for neck pain and degenerative disc disease (DDD).91 No concurrent, historical, or retrospective controls were identified. Fusion levels were determined by a painful and concordant response to disc injections. An unknown number of patients were excluded by the authors or declined surgery. Some potential patients (again, the number is unknown) were excluded because of psychological risk factors. The number of subjects lost to follow-up or who refused follow-up was not reported. There was no apparent standard assessment interval, and the intervals between the surgery and the reported assessment varied widely, from 2 to 7 years. Other interventions that the subjects might have received during this period-- which could have affected outcomes--are not reported. Of the reported cases, the mean numerical pain rating after surgery remained greater than 4 (of 10), and the Oswestry Disability Index score showed moderate-to-serious impairment in most of the select group of patients followed. No neck-specific functional outcomes were assessed. Only 18 patients out of an unknown number (between 38 and 175) who were operated on by the authors for neck pain and degenerative disc disease said that the surgery had 'met their expectations'.
  * Garvey, et al. (2002) reported on 87 of 112 (78%) retrospectively identified patients who underwent ACDF for a diagnosis of 'mechanical cervical spine pain' (defined by the authors as patients who had more neck pain than arm pain).92 Patients were evaluated 5 to 10 years after surgery. The number of patients evaluated or considered for surgery is unknown. The selection process and screening were not detailed. Other treatments received were not reported.

The group was heterogeneous for diagnosis: an unknown proportion of patients
had some radiculopathy, radiographic instability, or cervical deformity. The
validity of the outcomes reported is uncertain. For example, it is not clear
if pain and functional impairment measurements were recorded both before and
after surgery; if validated functional assessments for neck pain were used;
and whether subjects considered the occurrence of surgery to have been
advantageous to their litigation claim (78%). Only 58 of these 112 patients
(52%) reported feeling 'somewhat better' or 'much better' than they did before
their surgery; only 25 patients (23%) reported feeling at least 'somewhat
satisfied' with their neck condition on follow-up. The authors cited
historical controls treated by nonoperative care of neck pain alone, 21% of
whom reported complete pain relief and 49% who reported partial relief. These
cited 'control' outcomes were similar to the authors' reported surgical
outcomes.

  * Two additional studies are frequently cited to support surgical treatment of neck pain.93,94 Both are retrospective case series with poorly reported recruitment procedures and follow few acceptable study design methods for outcome evaluation. For example, in these studies surgical outcomes are based solely on surgeons' perceptions of patient improvement as opposed to validated outcome instruments. Simmons, et al. report that the operating surgeon determined that 30 of 31 (97%) patients undergoing ACDF for neck pain were "all found to have immediate lessening" of symptoms after surgery; they further state that in every case "all pain was gone in a week after surgery"94 This observation is unlike any recorded by validated outcomes measures or collected by independent examiners.



Carragee, et al.95 go on to state, "It is well documented that neck pain
without serious underlying disease shows wide and spontaneous variations in
severity and any accompanying impairment. Thus, none of these frequently
cited, uncontrolled studies can confidently estimate how much, if any, of the
reported improvement was due to a surgical intervention, how much was due to
natural history, and how much might be explained by various nonspecific and
unidentified factors. Although these studies are frequently cited as
demonstrating clear efficacy of cervical fusion for primary neck pain, none of
these were found to be scientifically admissible by the Neck Pain Task Force.
Instead, after critical review of the methods and data we found no clinical
evidence, even in the best-known studies purporting definitive efficacy, to
support the use of either cervical fusion or cervical disc arthroplasty in
patients with neck pain without radiculopathy or serious underlying
pathology."

In addition to the methodological shortcomings of these studies described by
Carragee, et al. (2008), there were further limitations. There was
indirectness regarding the Medicare population (mean ages ranged from 42 to 45
years) and the target condition, nonspecific axial neck pain, (the study
authored by Simmons, et al. included mostly [64%] of participants with
specific causes of neck pain i.e., fracture, radiculopathy, myelopathy). All
the studies had small sample sizes (n= 34-84) producing imprecise results.

In addition to these earlier primary studies, a single more recent RCT
compared anterior fusion surgery with multidisciplinary rehabilitation for the
treatment of individuals who were refractory to conservative treatment for
chronic whiplash-associated disorders (WAD).96 This study included 49 patients
(mean ages were 38 and 40 years for the surgery and rehabilitation groups,
respectively) with predominate midline neck pain, who had no neurological
abnormalities and no specific changes seen on X-ray and MRI. The primary
endpoint was the patient's perceived change in neck pain assessed on the
follow-up, using the disease-specific Balanced Inventory for Spinal Disorders
(BIS) questionnaire. Follow-up evaluations were performed at variable time
points ranging from 17 to 50 months. Analyses were performed by intention-to-
treat and per-protocol. At follow-up, 67% of the patients in the surgery group
and 23% (95% CI 15 to 64) in the rehabilitation group assessed improvements in
the ITT analysis. Corresponding proportions in the per-protocol analysis were
83% and 12%, respectively. This study was judged to have a high risk of bias
due to the lack of blinding or incomplete blinding, and the outcome
measurement (self-reported change in pain perception) was likely to be
influenced by the lack of blinding. Additionally, there was very serious
indirectness (all participants had neck pain caused by a motor vehicle
accident and the mean ages were well below the Medicare population), and
imprecision (small sample size and wide confidence intervals suggesting
variable effects).

Taking into consideration all the relevant studies, the certainty of evidence
was judged to be very low due to study design and execution limitations,
indirectness, and imprecision.

**Appropriate Use Criteria/Coverage Recommendations**

The North American Spine Society (NASS) assessed the appropriateness of
cervical fusion for axial neck pain without stenosis and concluded that the
surgical procedure was never considered appropriate.97 The authors
additionally commented, "There was a trend to be rarely appropriate for 2 or
greater level fusions, whereas there was more uncertainty for 1 level fusions.
Although uncertain, anterior procedures were overall favored over posterior or
anterior and posterior procedures."

In the 2023 NASS Coverage Recommendations3), the committee states "Concerning
the scenarios in which cervical fusion is not indicated, recent evidence-based
medicine reviews have concluded that there is little to no evidence that
fusion is an effective treatment for axial neck pain without neurological
symptoms." 3

Evidence-based, clinical practice decision-support guidance explicitly does
not recommend surgical intervention for the management of non-radicular neck
pain in adults due to a lack of high-quality data demonstrating benefit and
the possible risk of harm.98

****



Cervical fusion alone or in combination with other spine surgical procedures
is often performed for the management of multiple spinal conditions. There are
three overall categories: cervical radiculopathy, cervical myelopathy, and
unstable spine. There are multiple etiologies which can be revealed on imaging
including herniated disc, spinal stenosis, spinal degeneration, synovial cyst
and symptomatic pseudoarthrosis from non-union of prior fusion. In all cases
the history, physical exam findings and imaging must correlate with the
neurological deficits attributable to the affected region of the cervical
spinal cord and other causes must be excluded.

The natural disease course of cervical radiculopathy is improvement with time
and conservative measures so surgical management is reserved for refractory
cases or when motor weakness creates significant functional limitations
necessitating escalation of treatment. While the evidence supporting
conservative therapy is low quality there are multiple RCTs and systematic
review/meta-analysis as well as societal input and subject matter expert agree
on a trial of conservative measures prior to surgical interventions. There is
a paucity of data on how long the conservative period should be with reports
ranging from 6 weeks to 3 or more months. As the data on disease course finds
most improvement within the first 3 months a 12-week trial of conservative
management is established, however the policy does acknowledge the need for
some patients with progression during this time to shift to surgical
management.

Cervical myelopathy (degenerative and mixed) is typically treated surgically
due to the higher rate of neurological symptoms and risk of progression. In
mild cases resolution with conservative therapy is possible and a trial of
conservative treatment is indicated with education on progressive symptoms and
intervention if worsening. Guidelines consist of a 6-12-week trial and 12
weeks was selected to allow time for the natural history of resolution or
progression to determine if surgical intervention is necessary. In cases where
there are progressive symptoms with neurological deficits surgical
intervention prior to the 12-week time period can be considered.

In cases of unstable spine surgical intervention is necessary and there are
few alternative options to consider. Malignant or benign spinal tumors leading
to intractable pain or instability or anticipated instability due to treatment
may necessitate stabilization with fusion. In some cases, spinal infection
with destruction of bone and cervical kyphosis with cord compression may
require surgical intervention to stabilize the spine.

There is not sufficient evidence to support surgical intervention for axial
neck pain. Systematic review evaluating outcome for ACDF for axial neck pain
with and without radiculopathy or myelopathy reported low quality evidence and
the benefit of the surgery over time could not be established as compared to
nonsurgical treatment options. The remaining evidence reviewed concludes very
low quality and therefore this is not considered reasonable and necessary.
This is consistent with societal guidelines.

Investigation into the optimal surgical procedure has explored outcomes with
various approaches. While there are clear benefits and disadvantages of the
various approaches the overall outcome is largely equivalent. As there is no
evidence to support one surgical approach over another the decision for the
optimal surgical approach is determined by the surgeon and patients with
consideration of the pathology and evaluation of risk and benefits of the
various approaches. This is consistent with societal guidance and expert
opinion.