Historical aspects

In 1880 Strümpell published what is considered to be the first clear description of HSP. He reported a family in which two brothers were affected by spastic paraplegia. The father was said to be “a little lame”, suggesting autosomal dominant transmission.1 Both Strümpell and Lorrain added similar cases to the literature in subsequent years.2 3 Shortly after these landmark descriptions, numerous reported cases of HSP appeared in the literature. However, Pratt, who considered the presence of additional neurological features to be incompatible with the original descriptions, labelled many of these as HSP plus syndromes.4 Early reviews of these and other cases attempted to identify “pure” cases as had been described by Strümpell. However, the definition of “pure” varied among authors.5-8 It was Harding in 1981 who, after detailed clinical evaluation of 22 families, suggested criteria for classifying HSP into pure and complicated forms which have since been adopted and are discussed below.9 Further subdivision of pure HSP was also suggested by Harding based on the age of onset of the disease. It was found that families could be separated into two groups, one with onset before 35 years (type I) and the other with onset after 35 years (type II). There seemed to be clinical differences between the groups, with the type I patients having a slow …