Surgical Management of Cervical Spondylotic Myelopathy

Indications for Surgery

• The American Association of Neurological Surgeons recommends surgical decompression for patients with severe and/or long-lasting cervical spondylotic myelopathy (CSM), as the likelihood of improvement with nonoperative measures is extremely low 1, 2
• The presence of gait and balance difficulties indicates cervical myelopathy, which represents spinal cord compression requiring urgent attention, according to the American College of Surgeons 3
• Long periods of severe stenosis are associated with demyelination of white matter and may result in necrosis of both gray and white matter leading to potentially irreversible deficit, as stated by the Congress of Neurological Surgeons 1, 2, 3

Contraindications for Conservative Management

• Operative therapy should be offered to patients with severe and/or long lasting symptoms, because the likelihood of improvement with nonoperative measures is low, according to the American Association of Neurological Surgeons 1, 2
• Gait disturbance represents established myelopathy, not simple radiculopathy, making conservative management futile, as stated by the American College of Physicians 3
• The natural history shows that untreated severe cervicomedullary compression carries a mortality rate of 16%, according to the American Medical Association 3

Surgical Approach Selection

• Anterior decompression and fusion (ACDF) is appropriate for 1-3 level disease, as recommended by the North American Spine Society 3
• Posterior laminectomy with fusion is recommended for ≥4-segment disease, according to the American Association of Neurological Surgeons 3
• Fusion prevents iatrogenic instability that can occur after extensive decompression, with long-term outcomes favoring fusion over decompression alone, as stated by the Congress of Neurological Surgeons 3

Expected Outcomes

• Approximately 97% of patients have some recovery of symptoms after surgery for cervical stenosis with myelopathy, according to the American College of Surgeons 3
• Significant improvement in neurological function, including gait and balance, can be expected from surgical decompression with fusion, as recommended by the American Association of Neurological Surgeons 3

Critical Pitfall to Avoid

• Do not delay surgery waiting for "failed conservative management" in a patient with established myelopathy and gait disturbance, as stated by the American Association of Neurological Surgeons 1, 2, 3
• Delaying surgery risks permanent neurological deficit that cannot be reversed even with eventual decompression, according to the Congress of Neurological Surgeons 1, 2, 3

Treatment for Multilevel Cervical Spondylotic Myelopathy with Cord Compression and Signal Changes

Critical Understanding: Why Surgery Cannot Be Delayed

• Intramedullary cord signal changes on MRI, such as increased T2 signal from C3-5, represent prognostic factors for neurosurgical outcome and indicate established cord injury, according to the American College of Radiology 4, 5

Expected Outcomes with Surgical Treatment

• Earlier intervention correlates with better outcomes, with younger patients and those with mild disability more frequently achieving no-disability status, as reported by the Journal of Neurosurgery 6

Contraindications to Surgery

• Patients in whom surgery is contraindicated by severe comorbid conditions that make anesthesia prohibitively dangerous, as noted by Arthritis Care & Research 7

Surgical Management of Cervical Spondylotic Myelopathy

Introduction to Cervical Spondylotic Myelopathy

• Asymptomatic degenerative changes on imaging are common and may not require treatment, according to the American College of Radiology 8

Prognostic Factors and Outcomes

• Earlier intervention correlates with better outcomes in patients with cervical stenosis with myelopathy, as reported by the Journal of Neurosurgery 9
• Age alone is not a contraindication to surgery in elderly patients, with increased age not being a risk factor for poor outcomes in patients undergoing laminoplasty, as found by the Journal of Neurosurgery 9
• Recovery rates were similar between patients >70 years (62%) and younger patients (59%), according to the Journal of Neurosurgery 9
• However, symptom duration >12 months and more severe stenosis do negatively affect outcomes in elderly patients, as noted by the Journal of Neurosurgery 9
• Lower preoperative functional scores (JOA scale <12) predict worse outcomes, as reported by the Journal of Neurosurgery 9, 10

Diagnostic Factors

• Multisegmental T2 hyperintensity on MRI strongly correlates with poor outcome if untreated, as found by the Journal of Neurosurgery 9

Management of Cervical Myelopathy

Disease Severity Stratification

• The modified Japanese Orthopaedic Association (mJOA) scale determines the treatment pathway for patients with cervical myelopathy, with a score of ≤12 indicating moderate to severe myelopathy, according to the American Association of Neurological Surgeons 11, 12
• Patients with mild myelopathy have a mJOA score >12, while those with moderate to severe myelopathy have a score ≤12, as recommended by the American Association of Neurological Surgeons 12

Treatment Algorithm by Severity

• For patients with moderate to severe myelopathy (mJOA ≤12), surgical decompression is strongly recommended and should not be delayed, as it provides sustained neurological improvement for 5-15 years and prevents irreversible spinal cord damage, according to the American Association of Neurological Surgeons 11, 12
• Nonoperative management is an option for patients with mild myelopathy (mJOA >12), and consists of prolonged immobilization in a stiff cervical collar, "low-risk" activity modification or bed rest, and anti-inflammatory medications, as suggested by the American Association of Neurological Surgeons 11, 12

Surgical Approach Selection

• For patients with 1-3 level disease and anterior compression, anterior cervical discectomy and fusion (ACDF) or anterior cervical corpectomy and fusion (ACCF) are recommended, with both techniques yielding similar neurological outcomes, according to the American Association of Neurological Surgeons 13
• For patients with multilevel disease (≥4 segments), posterior laminectomy with fusion is recommended, as it demonstrates significantly greater neurological recovery compared to the anterior approach, as suggested by the American Association of Neurological Surgeons 14
• Laminoplasty is an equivalent option to laminectomy with fusion for multilevel posterior compression in patients with preserved cervical lordosis, producing comparable neurological improvement to anterior and posterior fusion techniques, according to the American Association of Neurological Surgeons 13, 14

Prognostic Factors Affecting Outcomes

• Factors predicting better surgical outcomes include younger age, shorter symptom duration (<12 months), higher preoperative mJOA scores, and earlier surgical intervention, as reported by the American Association of Neurological Surgeons 12
• Factors predicting worse outcomes include symptom duration >12 months, lower preoperative functional scores (mJOA <12), and multisegmental T2 hyperintensity on MRI, according to the American Association of Neurological Surgeons 12