neurologic disorders
Cervical Dystonia
Symptoms and Signs of Cervical Dystonia
Cervical dystonia symptoms may begin at any age but usually begin between ages 20 and 60, with a peak between ages 30 and 50. Symptoms usually begin gradually; rarely, they begin acutely and progress rapidly. Sometimes symptoms begin with a tremor that rotates the neck (in a no-no gesture). The cardinal symptom of cervical dystonia is Painful tonic contractions or intermittent spasms of the sternocleidomastoid, trapezius, and other neck muscles, usually unilaterally, that result in an abnormal head position Unilateral sternocleidomastoid muscle contraction causes the head to rotate to the opposite side. Rotation may involve any plane but almost always has a horizontal component. Besides rotational tilting (torticollis), the head can tilt laterally (laterocollis), forward (anterocollis), or backward (retrocollis, common whendopamine-blocking drugs are the cause). Similarly, in the caput form, the head may tilt laterally (laterocaput), forward (anterocaput), or backward (retrocaput). Patients may discover sensory or tactile tricks that lessen the dystonic posturing or tremor (geste antagoniste). Touching the face on the side contralateral to the deviation is an example. Noting whether a sensory trick is effective can help clinicians differentiate pathophysiologic dystonia from psychogenic dystonia. Such tricks typically do not lessen psychogenic tremor. The presence of overflow or mirroring also indicates that a pathophysiologic etiology (eg, genetic, idiopathic, brain injury) is likely. Overflow refers to involuntary dystonic movement in another part of the body, distant to the primary voluntary movement. In mirroring, when patients voluntarily move the affected side of their body, they involuntarily mimic that movement with the opposite side of the body. During sleep, muscle spasms disappear. Spasmodic torticollis ranges from mild to severe. Usually, it progresses slowly for 1 to 5 years, then plateaus. About 10 to 20% of patients recover spontaneously within 5 years of onset (usually in milder cases with onset at a younger age). However, it may persist for life and can result in restricted movement and postural deformity. 