Chemodnervation for cervical dystonia: A clinical review

Cervical dystonia (CD) is a focal dystonia characterized by involuntary contractions of neck muscles that result in patterned movements and abnormal postures of the head and neck that have a directional quality. CD is the most common form of dystonia presenting to the movement disorders clinic. Botulinum toxin is an effective treatment for cervical dystonia. It has become the first-line treatment for cervical dystonia with a satisfactory relief of symptoms reported in more than 80% of the cases. Multiple small and large scale studies proven that fact and provided Class-A evidence for the benefit. However, 20% of the patients discontinue treatment due to adverse effects, treatment failure and other reasons. With the proper knowledge of toxins and the anatomy of the neck, much better results can be achieved with fewer and self-limiting adverse effects as compared to other modalities. However, the expert consensus recommendations are lacking to guide clinicians for optimal use of botulinum toxin for cervical dystonias. This paper discusses the different available treatments, botulinum injection techniques and the adverse effects involved with the procedure.