Cervical Spine in Down’s Syndrome

FACTS

  • DS patients have C1-2 abnormalities with widened ADI of varying degrees
  • incidence is 20%, but generally symptomatic in only 1-2%
  • pathophysiology: laxity of TAL, though decreases with age as it stiffens

HPI

universal ROS
  • gait difficulties
  • neck pain
  • limited neck motion
  • clumsiness
  • sensory deficits
  • myelopathy screen

PHYSICAL EXAM

Universal neuro exam
  • comment on neck posture

IMAGING

  1. XR Cervical spine: measure ADI and PADI
  1. +/- Cervical flex-ex
  1. +/- MRI C-spine without contrast (see below)
Measure ADI: distance between anterior margin of dens and closest point of anterior arch of C1 (normal 2-4mm) and PADI (neural canal width): back of odontoid to anterior aspect of posterior C1 ring.
Measure ADI: distance between anterior margin of dens and closest point of anterior arch of C1 (normal 2-4mm) and PADI (neural canal width): back of odontoid to anterior aspect of posterior C1 ring.
A/P
  • counsel: most will NOT progress to instability of initial imaging are normal
 
Surgical Management
  • Asymptomatic atlantoaxial subluxation (AAS)
    • ADI ≤ 4.5mm AND PADI ≥ 14mm: no further imaging
    • ADI > 4.5 mm OR PADI < 14 mm: MRI Cervical
      • MRI showing neural impaction: fusion
      • MRI showing no neural impaction: follow-up in 1 year, prohibit high risk activities in the interim
  • Symptomatic AAS
    • if ADI > 4.5 mm or PADI < 14 mm → C1-C2 fusion
  • AAS w/ os odontoideum: fusion (very high risk of sudden subluxation