Effective treatment of cervical dystonia with botulinum toxin: Review

Cervical dystonia is the most common form of focal dystonia in adults. It is characterized by involuntary contraction of neck muscles, causing abnormal posture and movements of the head. Pain is present in about 75% of patients and usually considered the major cause of disability in these patients. Botulinum toxin injection into the dystonic neck muscles is considered the treatment of choice for patients with cervical dystonia. Botulinum toxin binds presynaptically to cholinergic nerve terminals causing decreased release of acetyl choline and reduction in muscle tone. It is important to precisely identify the sites of pain and the muscles responsible for the abnormal posture to have better success. The incidence of complications can be reduced by the proper choice of dose for specific muscles. In this article, the authors review the clinical features, course, and pathophysiology of cervical dystonia. Also reviewed are the chemistry, pharmacology, mechanism of action of botulinum toxin along with practical aspects of its use and complications associated with its use in the treatment of cervical dystonia.