Hereditary spastic paraparesis: a review of new developments.

Hereditary spastic paraparesis (HSP) or the Strümpell-Lorrain syndrome is the name given to a heterogeneous group of inherited disorders in which the main clinical feature is progressive lower limb spasticity. Before the advent of molecular genetic studies into these disorders, several classifications had been proposed, based on the mode of inheritance, the age of onset of symptoms, and the presence or otherwise of additional clinical features. Families with autosomal dominant, autosomal recessive, and X-linked inheritance have been described.