ABSTRACT
The restless legs syndrome (RLS) was probably described over 300 years ago by
Willis (1). Descriptions were then sporadic until the 1940s when Ekbom
described all of the primary and secondary features of RLS minus periodic limb
movements in sleep (PLMS), which were subsequently described by Lugaresi et
al. when polysomnography became available in the mid-1960s (2,3). Subsequent
descriptions of RLS through various versions of the International Classification
of Sleep Disorders (4,5) and the International Restless Legs Syndrome Study
Group (IRLSSG) (6,7) were attempts to discriminate essential from nonessential
diagnostic features.
