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Information

Skull and Spine Disorders

= encroachment on central spinal canal, lateral recess, or neuroforamen by bone / soft tissue

Cause:

  1. Congenitally short pedicles
    1. idiopathic
    2. developmental: Down syndrome, achondroplasia, hypochondroplasia, Morquio disease
  2. Acquired:
    1. Hypertrophy of ligamentum flavum = buckling of ligament ← joint slippage in facet joint osteoarthritis (most common)
    2. Facet joint hypertrophy
    3. Degenerated bulging / herniated disk
    4. Spondylosis, spondylolisthesis
    5. Surgical fusion
    6. Fracture
    7. Ossification of posterior longitudinal ligament
    8. Paget disease
    9. Epidural lipomatosis

Age: middle-aged for congenital cause / elderly during 6th–8th decade for acquired cause; M >F

Location: generally involves lumbar spinal canal; cervical spinal canal may be similarly affected

Cervical Spinal Stenosis!!navigator!!

Location: multiple levels in mid- and lower cervical spine

  • sagittal diameter of cervical spinal canal <13 mm
  • hourglass narrowing of thecal sac with scalloping of the dorsal + ventral margins of the cord
  • greater degree of stenosis in hyperextended position ← buckling of ligamenta flava:
    • ± spinal block in hyperextended neck on AP views

Lumbar Spinal Stenosis!!navigator!!

Cause:

  1. Achondroplasia:
    • narrowed interpediculate distance progressive toward lumbar spine
  2. Paget disease: bony overgrowth
  3. Spondylolisthesis
  4. Operative posterior spinal fusion
  5. Herniated disk
  6. Metastasis to vertebrae
  7. Developmental / congenital

Age: presentation between 30 and 50 years of age

  • often asymptomatic until middle age (until development of secondary degenerative changes); low back pain
  • “neurogenic / spinal claudication” = bilateral lower extremity pain, numbness, weakness worse during walking / standing + relieved in supine position and flexion
  • cauda equina syndrome: paraparesis, incontinence, sensory findings in saddlelike pattern, areflexia
  • sagittal diameter of spinal canal <16 mm (normal range in adults: 15–23 mm)
  • diminished amount of CSF + crowding of nerve roots
  • unusual small quantity of contrast material to fill thecal sac
  • constricted anteroposterior + interpediculate diameter of spinal canal
  • dural sac area <100 mm2
  • hourglass configuration of thecal sac (SAG view)
  • triangular / trefoil shape of thecal sac (AXIAL view)
  • redundant serpiginous nerve roots above + below stenosis
  • thickened articular process, pedicles, laminae, ligaments
  • bulging disks

Outline