Pathophysiology and pharmacotherapy of spasmodic torticollis: a review.

The few existing neuropathological, neurochemical, and neuropharmacological studies have shed little light on the pathophysiology of spasmodic torticollis (ST). The relevance of experimental ST in animals and drug-induced ST in man to idiopathic ST is unclear. Most pharmacotherapeutic endeavors have focused on drugs affecting basal ganglia function. Unfortunately, problems of sample size, clinical heterogeneity of patient population, research design, objective evaluation of response, documentation of key data, and adequacy of duration of follow-up make interpretation of published results difficult. Because of the heterogeneity of ST, investigations aimed at establishing a neurotransmitter profile for each patient by observing the acute response to a test dose of drugs affecting cholinergic, dopaminergic, serotonergic, and gamma-aminobutyric acid systems may provide a more rational basis to the selection of treatment.