Metaphyseal Chondrodysplasia, Schmid Type

Schmid metaphyseal chondrodysplasia is a rare disorder characterized by moderately short stature with short limbs, coxa vara, bowlegs and an abnormal gait.

Epidemiology

Prevalence is unknown.

Etiology

The disorder is caused by mutations in the COL10A1 (6q21-q22) gene encoding the collagen alpha-1(X) chain.

Diagnostic methods

The condition is usually diagnosed during the second or third year of life. Diagnosis relies on detection of the metaphyseal lesions at radiography.

Differential diagnosis

Hypochondroplasia (see this term) and sequelae from rickets are the principle differential diagnoses. Other metaphyseal dysplasias (such as cartilage-hair hypoplasia or Jansen type metaphyseal chondrodysplasia; see these terms) can be excluded as they are associated with very short stature and other features.

Antenatal diagnosis

Prenatal diagnosis should not be proposed for this disease.

Genetic counseling

Schmid metaphyseal chondrodysplasia is transmitted in an autosomal dominant manner. Genetic counseling may be recommended with a 50% risk of recurrence.

Management and treatment

Orthopedic correction is the only possible treatment.