Diagnosis

Spinal stenosis

Etiology

Cause [3em][znh][c5m]

• Aquired spinal stenosis (91%):

  • Degenerative osteoarthritis of the spine or spondylosis

  • Space-occupying lesions

    • Synovial or neural cyst

    • Neoplasm/lipoma

    • Traumatic/postoperative changes: Fibrosis

    • Skeletal disease: Ankylosing spondylitis, rheumatoid arthritis, or Paget disease

• Congenital spinal stenosis (9%):

  Spinal dysraphism, segmentation failure, achondroplasia, osteopetrosis, early vertebral arch ossification, shortened pedicles, thoracolumbar kyphosis, apical vertebral wedging, anterior vertebral beaking (Morquio syndrome), osseous exostosis, spina bifida, spondylolisthesis, and myelomeningocele

Pathophysiology [zrz][c5m][kgy]

1. Spinal stenosis is part of the aging process (common in the lumbar and cervical level)

2. Degenerative osteoarthrites lead to narrowing of the central canal and neural foramina

   • Facet joints hypertrophy/arthropathy

   • Ligamentum flavum hypertrophy

   • Posterior longitudinal ligament

   • Vertebral body osteophyte formation (bone spurs)

   • Intervertebral disk herniation

   • Loss of disc height

   • Epidural fat

   • Spondylolisthesis (translation of one vertebral body anteriorly or posteriorly)

3. No clear association between spinal stenosis and the presence of symptoms

4. Mechanical compression from spinal stenosis may result in:

   • Reduced blood flow --> neurogenic claudication --> spinal ischemia

   • Myelopathy

   • Radicular pain

   • Decreased impulse conduction at the nerve roots: Paresis/paresthesia

Risk factors [c5m]

• Age

• Heavy work

• BMI

• Family history

Complications [c5m][kgy]

• Lower extremity radicular pain

• Muscle wasting

• Disability

• Spinal deformity

• Pulmonary embolism

• Reduced quality of life

• Cauda equina or conus medullaris syndrome

Epidemiology

Incidence per 100.000 [wur][tsc][3vb][f9h]

Approach

• Neurology: motor, sensory, reflex, anal sphincter tone

• Vascular status

• Blood test: Sedimentation rate, ALP, calcium, serum protein electrophoresis

• MRI

• CT myelography

• Electromyography: not routinely used, may be helpful in some special clinical conditions where the radiographic images cannot explain the symptoms of patients [znh]

Diagnostic criteria: [bdg]

1. Clinical findings: age, neurogenic claudication, radiating buttock/leg pain, exacerbated with lumbar extension and relieved with lumbar flexion, wide based gait

2. Radiological findings:

   • Normal diameter of the lumbar canal: 22-25 mm

   • Relative spinal stenosis: 10-12 mm

   • Diameter <10 mm is considered absolute stenosis

Treatment

1. Prophylaxis: Exercise, diet or changes in lifestyle

2. Conservative treatment: [bdg][znh][c5m]

   • Lifestyle modifications (weight loss, quit smoking), NSAIDs, muscle relaxants, physiotherapy (strength/flexibility exercises, balance training, acupuncture), cervical collar, corset

   • Epidural injections: local anesthetic injection with or without steroids (short term effect)

3. Surgery: severe symptoms and/or progressive myelopathy

   • Decompressive laminectomy with or without fusion

   • Interspinous spacers

   • Lumbar fusion: transforaminal lumbar interbody fusion (TLIF) and oblique lumbar interbody fusion (OLIF)

   • Minimally invasive posterior microdecompression or TLIF (MI-TLIF): percutaneous endoscopic interlaminar and transforaminal microdecompression

Differential diagnoses

Amyotrophic lateral sclerosis, Ankylosing spondylitis, Brain tumor, Cauda equina syndrome, Chronic limb ischemia, Compression fracture, Discitis, Hydrocephalus, Hyperparathyroidism, Metastatic bone tumors, Multiple myeloma, Multiple sclerosis, Myofascial pain, Osteoarthritis, Osteomalacia, Osteomyelitis, Peripheral neuropathy, Polyneuropathy, Rheumatoid arthritis, Scoliosis, Spinal cord infarction, Spinal cord infection, Spinal cord tumor, Spinal disc herniation, Spinal hematoma, Spondylodiscitis, Spondylolisthesis, Spondylolysis