Sensory trick and benefit from botulinum toxin in cervical dystonia

Dystonia, which is defined as uncontrolled and sometimes painful muscle movements (spasms), is the third most common movement disorder. A movement disorder is a group of nervous system (neurological) conditions that cause abnormal increased movements. It is estimated that as many as 300,000 people in North America may be affected. Cervical dystonia (CD) is a painful chronic neurological condition in which the neck involuntarily turns to the left, right, upwards, and/or downwards. This may be associated with shaking of the head and neck. Without adequate diagnosis and treatment, CD can be highly disabling. Botulinum toxin is a Food and Drug Administration (FDA) approved treatment for dystonia. Botulinum toxin is neurotoxic, meaning it alters the structure or function of the nervous system, and it is produced by the bacterium Clostridium botulinum. In the correct dose, it has therapeutic benefits. Most patients with cervical dystonia eventually require it for management of bothersome cervical dystonia. Sensory tricks are specific maneuvers that alleviate dystonia in a manner that is not easily physiologically perceived as necessary to counteract the involuntary movement. These vary considerably across patients, and may include touching the lower part of face, a towel around the neck or even yawning. Sensory tricks are thought to be most effective early on in the disease course and may completely alleviate posturing and associated disability in some individuals.

Understanding the therapeutic potential of sensory tricks by assessing comparative benefit with botulinum toxin, can directly improve pain and disability in patients suffering from this rare condition. The study will examine the effectiveness of sensory tricks relative to the dose of botulinum toxin required for symptom benefit. It will further the literature on non-pharmacological approaches to treatment in dystonia.