Treatment of Cervical Spondylotic Myelopathy
For moderate to severe CSM (mJOA score ≤12), surgical decompression is strongly recommended and should not be delayed, with benefits maintained for 5-15 years postoperatively. 1
Treatment Algorithm Based on Disease Severity
Mild CSM (mJOA Score >12)
For patients with mild myelopathy, either surgical decompression or nonoperative therapy can be offered for the first 3 years, though this equivalency is based on Class II evidence with methodological limitations including nonblinded allocation and potential selection bias. 1, 2
Nonoperative therapy components include:
- Prolonged immobilization in a stiff cervical collar 1
- "Low-risk" activity modification or bed rest 1
- Anti-inflammatory medications (NSAIDs) 1
- Physical therapy focusing on neck stabilization and range of motion 2
Critical caveat: The evidence supporting nonoperative management is limited to 3 years, and it remains unclear whether patients deteriorate significantly after this timepoint. 1 Additionally, patients with symptoms present for less than one year before surgery show better results across all treatment modalities, making early surgical consideration reasonable even in mild disease. 3
Moderate to Severe CSM (mJOA Score ≤12)
Surgical decompression is the definitive treatment, demonstrating statistically significant improvement in mJOA scores beginning at 6 months and continuing through 24 months postoperatively, with benefits maintained for 5-15 years. 1, 2, 3
Patients with severe disability (mean mJOA score of 9.5) show significant improvement after surgical intervention (mean mJOA score 10.9 at 2 years postoperatively). 1
Surgical Approach Selection
The choice of surgical technique depends on the number of levels involved, location of compression, and cervical alignment. 2, 3
Anterior Approaches
For 1-3 level disease with anterior compression at the disc level:
Anterior cervical discectomy with fusion (ACDF) or anterior cervical corpectomy with fusion (ACCF) are recommended, yielding similar results with improvement rates of approximately 73-74%. 1, 2
Anterior plating is standard of care, achieving 97% fusion rates when combined with bone graft and providing immediate stability. 4
ACDF and ACCF with anterior plating allow for equivalent fusion rates between these techniques. 1
If anterior fixation is not used, ACCF may provide a higher fusion rate than multilevel ACDF, but is associated with a higher graft failure rate. 1
ACDF is preferred for short segment decompression when technically feasible, particularly to avoid the late deterioration associated with laminectomy alone. 1
Posterior Approaches
For multilevel disease (≥4 segments), developmental canal narrowing, or posterior compression:
Laminoplasty is recommended, preserving motion and reducing axial neck pain, with comparable improvement to anterior approaches. 1, 2, 3
Laminectomy with fusion prevents post-laminectomy kyphosis and demonstrates significantly greater neurological recovery (average 2.0 Nurick grade improvement) compared to anterior approach (1.2 grade improvement) or laminectomy alone (0.9 grade improvement). 2, 3
Laminectomy with lateral mass fusion resulted in neurological improvement in 97% of patients with mean JOA score improvement from 12.9 to 15.6. 3
Critical Surgical Pitfall
Laminectomy alone (without fusion) should be avoided due to a concerning 29% late deterioration rate, increased risk of postoperative kyphosis, and postoperative instability. 1, 4, 2, 3 While both anterior and posterior approaches produce comparable near-term improvements, laminectomy without fusion is associated with late deterioration that significantly impacts long-term outcomes. 1
Prognostic Factors
Better surgical outcomes are associated with:
- Younger age 2, 5
- Shorter duration of symptoms (particularly <1 year) 2, 3, 5
- Better preoperative neurological function 2, 5
Poor prognostic indicators requiring urgent surgery include:
- Progressive signs and symptoms 4, 5
- Presence of myelopathy for 6 months or longer 5
- MRI-documented severe spinal cord compression with increased T2 signal indicating edema or myelomalacia 4
Common Clinical Pitfalls to Avoid
Delaying surgery in progressive myelopathy with cord signal changes can worsen outcomes and lead to irreversible spinal cord damage. 4, 3 Long periods of severe stenosis result in potentially irreversible damage to the spinal cord. 3
Do not delay appropriate referral for patients with:
- Progressive neurological symptoms 2
- Hand dysfunction, lower extremity weakness, gait disturbance 4
- Bilateral symptoms indicating cord compression 4
- MRI evidence of cord compression with T2 signal changes 4
Smoking cessation efforts should not delay surgery in patients with progressive myelopathy and cord signal changes. 4
Inadequate stabilization during surgery can lead to cage movement and pseudarthrosis, occurring in approximately 10.9% of cases. 3