What are the physical characteristics of Metatropic Dysplasia?

Initially, patients have shortened limbs and trunk height is preserved (short-limbed dwarfism). As the condition progresses, kyphoscoliosis of the spine develops that decreases trunk height (short-trunk dwarfism). Apparent shortening of the limbs also occurs over time, due to progressive joint contractures.

Face and Skull:

• Average facial features
• Macrocephaly due to hydrocephalus

Trunk, Chest and Spine:

• Small and narrow chest
• Pectus carinatum (pigeon chest) or pectus excavatum (depressed breast bone)
• Severe kyphoscoliosis
• In infancy, “coccygeal tail:” a prolongation of the normal tailbone consisting of cartilage material

Arms and legs:

• Signficantly shortened limbs with a characteristic dumb-bell shape
• Enlarged joints
• Progressive joint contractures during childhood

What are the x-ray characteristics?

The radiographic features of Metatropic Dysplasia include small, flat, diamond-shaped vertebral bodies in early infancy due to defective ossification. Later, platyspondyly and anterior wedging of vertebral bodies are characteristic. Appearance of a hump-like build-up of bone in both the central and posteriorportions of vertebral end plates, markedly in the lower posterior and upper lumbarspine. The thorax is narrow and ribs are short in both infancy and early childhood. Limbs are also short with marked metaphyseal flare and epiphyseal dysplasia. Deformed capital femoral epiphyses. Hyperplasia of proximal femoral metaphyses. The capital femoral epiphyses are typically deformed. Hyperplasia of proximal femoral metaphyses is usually observed. Finally, hypoplasia of basilar pelvis with crescent-shaped iliac crests and low-set anteriosuperior iliac spines is characteristic.

• What are the physical characteristics of Metatropic Dysplasia?
• How is the diagnosis made?
• Problems in the musculoskeletal system
• Problems elsewhere in the body
• What are things to watch out for?
• References