Morquio Syndrome

  • Etiology: lysosomal storage disorders which have excessive accumulation of mucopolysaccharides secondary to deficiencies in lysosomal hydrolase enzymes responsible for degradation of mucopolysaccharides
  • Imaging:
    — Osteopenia
    — Enlarged cranium with thickened calvarium
    — Anteroinferiorly beaked oval vertebral bodies which are hypoplastic
    — Dysplastic capital femoral epiphyses
    — Short and wide metacarpals and phalanges that taper proximally – clawlike hand
    — Dysostosis multiplex
    — Skull
    — Large and dolichocephalic
    — Poorly developed mastoids and paranasal sinuses
    — Elongated J shaped sella turcica
    — Malformed teeth
    — Thick diploic space
    — Spine
    — Gibbus deformity at T-L junction due to defective development of anterosuperior portion of vertebral bodies causing central beaking of vertebral bodies
    — Vertebral bodies oval and slightly flattened
    — Odontoid hypoplasia
    — Pelvis
    — Superior acetabular region underdeveloped -> widened acetabular roof and high acetabular angle (flared pelvis)
    — Coxa valga
    — Femoral heads delayed in development and dysplastic
    — Chest
    — Oar shaped ribs – widened but taper at vertebral margins
    — Thick, short, wide clavicles
    — Tubular bones
    — Short broad bones with diaphyseal and metaphyseal expansion
    — Delay in epiphyseal ossification
    — Cortical thinning
    — Changes more marked in upper than lower extremities
    — Constriction of humeral and femoral necks with varus deformities
    — Distal portions of radius and ulna taper, altering carpal angle
    — Hand
    — Diffuse osteopenia, cortical thinning
    — Proximal tapering of 2nd – 5th metacarpal bones
    — Proximal and middle phalanges short and wide
    — Terminal phalanges are hypoplastic
    — Carpal bones small and deformed
  • DDX: Universal platyspondyly unique to Morquio within mucopolysaccharidoses
  • Complications:
  • Treatment:
  • Clinical:
    — Is mucopolysaccharidoses Type IV
    — Short trunk
    — Short stature, lax joints, stiff neck
    — Die young
    — Have congenital heart disease

Radiology Cases of Morquio Syndrome

Radiograph of hands in Morquio syndrome
AP radiograph of the hands shows bilaterally wide metacarpals, irregular carpal bones and metaphyseal flaring in the distal radius and ulna.
Radiograph of hypoplasia of the odontoid in Morquio syndrome
Lateral vintage conventional tomogram in the midline of the cervical spine shows hypoplasia of the odontoid process of the C2 vertebral body.
Spine radiograph of Morquio syndrome
AP radiograph of the thoracolumbar spine (left) shows ribs that are widened but then taper at their vertebral insertions (oar-shaped ribs). Lateral radiograph of the thoracolumbar spine (right) shows the vertebral bodies to be hypoplastic and oval in appearance and to be beaked anteriorly, resulting in a gibbus deformity at the thoracolumbar junction. Overall there is diffuse platyspondyly of the spine.
Radiograph of gibbus deformity of the spine in Morquio syndrome
Lateral radiograph of the spine shows central beaking of the anterior aspect of the vertebral bodies resulting in a short-segment thoracolumbar kyphosis (gibbus deformity). There is also diffuse flattening of the vertebral bodies (platyspondyly).
Pelvis radiograph of Morquio syndrome
AP radiograph of the pelvis shows bilateral flattening of the proximal femoral epiphyses with bilateral subluxation and dislocation of the femoral heads.