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Prevalence is estimated at around 1/100,000.

The disorders are characterized by platyspondyly (flattened vertebrae) and marked hip and knee metaphyseal lesions. The different forms of spondylometaphyseal dysplasia are distinguished by the localization and severity of involvement of the affected metaphyses. The most common form is the Kozlowski type of spondylometaphyseal dysplasia (see this term). The form of spondylometaphyseal dysplasia referred to as the 'corner fracture' or Sutcliffe type (see this term) results in very severe coxa vara. A rarer form (Algerian or Schmidt type; see this term) appears to have more predominant knee involvement. Lastly, some moderate forms are at present not well classified and other forms have also been identified, including type A4, and an axial type associated with retinitis pigmentosa and optic atrophy (see these terms). Spondylometaphyseal dysplasia may also occur in association with other clinical manifestations such as facial dysmorphism and dentinogenesis imperfecta (see this term).

Kozlowski type of spondylometaphyseal dysplasia results in severe kyphoscoliosis and is caused by mutations in the TRPV4 gene (locus 12q24.1).

Kozlowski type of spondylometaphyseal dysplasia is transmitted in an autosomal dominant manner, as well as the form of spondylometaphyseal dysplasia referred to as the 'corner fracture' or Sutcliffe type and the Algerian (or Schmidt) type. Some moderate forms also generally appear to be transmitted as autosomal dominant traits. Several autosomal recessive forms have also been identified, including type A4 and an axial type associated with retinitis pigmentosa and optic atrophy. A form of spondylometaphyseal dysplasia with X-linked transmission has also been reported (see this term).