DYSMELIA

'Dysmelia' (from Greek Δύσ - = "bad" plus μέλος (plural μέλεα) = "limb") is a congenital disorder referring to the limbs.
Dysmelia can refer to

★ missing (aplasia) limbs: amelia, oligodactyly, congenital amputation

★ malformation of limbs: ectrodactyly, phocomelia, syndactyly, brachydactyly, clubfoot

★ too many limbs: polymelia, polydactyly, polysyndactyly

Contents

Occurrence rate

Causes

Occurrence rate

Birth defects involving limbs occur in 1 per 1000.

Causes

Dysmelia can be caused by

★ inheritance of abnormal genes, e.g. polydactyly, ectrodactyly or brachydactyly, symptoms of deformed limbs then often occur in combination with other symptoms (syndromes)

★ external causes during pregnancy (thus not inherited), e.g. via amniotic band syndrome

★ teratogenic drugs (e.g. thalidomide, which causes phocomelia) or environmental chemicals

★ ionizing radiation (atomic weapons, radioiodine, radiation therapy)

★ infections

★ metabolic imbalance