What are the manifestations and treatment options for lumbar myelopathy?

Manifestations and Treatment of Lumbar Myelopathy

Lumbar myelopathy is a rare condition requiring prompt diagnosis and surgical intervention to prevent permanent neurological damage and improve quality of life.

Clinical Manifestations

Lumbar myelopathy presents with a characteristic pattern of neurological symptoms:

• Motor symptoms:

  • Progressive bilateral lower extremity weakness 1
  • Paraparesis or paraplegia 1
  • Hyperreflexia in lower extremities 2
  • Gait instability and deterioration 3, 2

• Sensory symptoms:

  • Back or leg pain 1
  • Sensory loss below the level of compression 1, 3
  • Radicular pain 3, 2

• Autonomic dysfunction:

  • Sphincter dysfunction 1

• Other presentations:

  • Subjective lower limb weakness that may be misdiagnosed as lumbar pathology 4
  • Symptoms may develop acutely or progress gradually over months 2, 4

Diagnostic Evaluation

Imaging

• MRI of the spine is the gold standard for diagnosis of lumbar myelopathy 1, 3, 5

  • Shows lesions in the dorsal column of the spinal cord 1
  • Can identify spinal cord compression and surrounding structures 3
  • Helps differentiate between compressive and non-compressive myelopathy 3

• CT myelography may be useful for:

  • Pre-surgical planning 1
  • Patients with contraindications to MRI 1
  • Further evaluation of arachnoid cysts/webs or ventral cord herniation 1

Additional Testing

• Electromyography and nerve conduction studies may help distinguish myelopathy from other neurological conditions 1

Etiology of Lumbar Myelopathy

Lumbar myelopathy can result from various causes:

1. Compressive causes:

   • Lumbar spinal stenosis 2, 6
   • Disc-osteophyte complexes 1
   • Spondylolisthesis 2
   • Ligamentum flavum hypertrophy 6
   • Tethered cord syndrome 2

2. Iatrogenic causes:

   • Intrathecal chemotherapy (methotrexate, cytarabine, cisplatin, carmustine, thiotepa) 1
   • Radiation-induced myelopathy 1

3. Other causes:

   • Vascular malformations 1
   • Metabolic disorders 1
   • Rare genetic disorders (e.g., Maroteaux-Lamy syndrome) 6

Treatment Approach

Surgical Management

Surgical decompression is the primary treatment for compressive lumbar myelopathy and should be performed promptly to prevent irreversible spinal cord injury 3, 2, 7.

• Surgical techniques:

  • Laminectomy with or without fusion 3, 2
  • Segmental sublaminoplasty 2
  • Minimally invasive approaches when appropriate 2

• Indications for surgery:

  • Moderate to severe myelopathy 7
  • Progressive neurological deterioration 7
  • Failure to improve with conservative management 7

Medical Management

For iatrogenic or medication-induced myelopathy:

• Discontinuation of causative agent is essential 1
• For methotrexate-induced myelopathy, high-dose folate metabolites may be considered 1
• For steroid-responsive conditions, steroids injected via lumbar route might be beneficial 1

Supportive Care

• Physical therapy and rehabilitation to improve function and prevent complications
• Management of neuropathic pain if present
• Monitoring for and addressing bowel/bladder dysfunction

Prognosis

• Recovery is variable and depends on:

  • Pretreatment neurological status 3
  • Duration of symptoms before treatment 3, 4
  • Extent of spinal cord damage 3
  • Underlying cause 1

• Better outcomes are associated with:

  • Early diagnosis and intervention 3, 4
  • Ambulatory status at presentation 3
  • Slower development of motor deficits 3
  • Complete surgical decompression 3

Important Considerations and Pitfalls

• Misdiagnosis risk: Lumbar myelopathy may be misdiagnosed as peripheral neuropathy or lumbar radiculopathy, especially when presenting with subjective lower limb weakness 4

• Diagnostic delay: Symptoms may be subtle initially, leading to delayed diagnosis and treatment 4

• Tandem stenosis: Consider the possibility of concurrent cervical or thoracic stenosis in patients with lumbar myelopathy 4, 6

• Iatrogenic causes: Always review medication history, especially in patients receiving intrathecal chemotherapy 1

• Post-surgical monitoring: Close follow-up is essential to detect any recurrence or progression of myelopathy 2, 4