Pii: S0304-3959(01)00292-5

For 20 years, botulinum toxin A has been used for treating a variety of disorders characterized by pathologically increased muscle contraction. Current research efforts focus on new areas of application for botulinum toxin A in speci®c pain therapy, particularly in primary headache syndromes and in myofascial pain syndromes of the neck, shoulder girdle and back. This opens up new options for patients with hitherto therapy-resistant chronic pain syndromes. From a scienti®c view, it offers new perspectives for basic research and clinical analyses of these syndromes. There is also a need to rethink and analyze the modes of action of botulinum toxin A. The use of botulinum toxin A in pain therapy, however, calls for a detailed knowledge of functional anatomy and for expertise in practical applications.