Clinical Journal of Pain. 23(1):62-66, January 2007.
Authors and affiliations: Bentley, Alison J.*, Rosman, Kevin D., Mitchell, Duncan PhD.
Objectives: The sensations of restless legs syndrome (RLS) are described as paresthesias [tingling or pricking] and dysesthesias [burning or itching], sensations which also occur in neuropathic pain [pain sensations that continue after the initial cause has resolved, as after shingles – sometimes described as an “alarm system malfunction.”]. Whether validated pain assessment tools can be used to measure the quality and severity of RLS sensations has not been explored.
Methods: Patients with RLS (n=25) completed the RLS severity scale of the International Restless Legs Syndrome Study Group, the McGill Pain Questionnaire (MPQ), and a Visual Analog Scale. Words chosen frequently were also compared with those describing different pain types.
Results: The International Restless Legs Syndrome Study Group RLS severity scale score correlated significantly with the Pain Rating Index, and number of words chosen derived from the MPQ, but not with the visual analog scale estimate of pain intensity. The words chosen by patients with RLS showed no significant correlation with words chosen by patients with either neuropathic or nociceptive pain. [Nociceptive pain signals usually resolve when the injury or source of pain is resolved.]
Discussion: The quality and severity of the sensation of RLS can be measured on the MPQ, and severity calculated from MPQ indices correlates significantly with a standard RLS severity measure. Thus the nonpainful sensations of RLS appear to be a subclinical form of pain. [Subclinical: not yet identifiable via clinical findings/tests.]