Meagan Smith

Cervical Dystonia

movement disorder characterized by motor manifestations, primarily involuntary muscle contractions causing twisting movements and abnormal postures

Persistent co-contraction of agonists and antagonistsPain is the primary cause of disability in patients with CD and

occurs in 2/3 to ¾ of patientsStress or self-consciousness and walking/fatigue/carrying objects

increased symptoms in >70% patientsAlso referred to as spasmodic torticollisnon-motor component including abnormalities in sensory and

perceptual functions, as well as neuropsychiatric, cognitive and sleep domains

widespread abnormalities detected in non-motor brain regions in functional imaging studies of patients with dystonia

Onset of symptoms occurres mainly between 40-60 yoFemale > malePrimary CD – idiopathic cause with no history of a secondary

cause for their symptomsOften gradual onset of symptoms

Secondary CD may have abnormal birth or developmental history, exposure to drugs known to cause dystonia (tardive dystonia), neurological illness,or recent traumaOften more acute onset, marked limitation of ROM, absence of

sensory tricks and lack of improvement after sleepRecommended if patient is < 40 yo to test for Wilson disease as this

often has dystonia associated with itTardive dystonia can be induced by long-term neuroleptic

medication, antiemetic agents or even some antivertiginous agents

Non-motor features

Sensory abnormalitiesNeuropsychiatric abnormalities

Temporal discrimination

Spatial discriminationVibration

Risk for Anxiety Risk for Depression

Neuropsychiatric abnormalitiesWith regard to depressive disorders, these appear to be

frequent in cervical dystonia The severity of depression in patients with dystonia is

usually not correlated with the severity of dystonia, suggesting a primary rather than a secondary abnormality.

some proportion of depression in patients with dystonia may be secondary to motor symptoms and pain as improvement in mood does occur with successful treatment of dystonia

In contrast to depression, anxiety disorders do not seem to represent a primary non-motor feature of dystonia

mild sensory symptoms such as discomfort in the neck months before cervical dystonia develops

Overt sensory signs in a patient with dystonia would indicate diagnoses other than primary dystonia; for example, some heredodegenerative forms of dystonia that cause sensory neuropathy, an incidental second disorder causing the sensory disturbance or secondary mechanical complications from abnormal postures, e.g. nerve root entrapment and carpal tunnel syndrome

Pain–pressure thresholds have been found to be two times lower in patients with dystonia

Geste antagonisteThe 'sensory trick' indicates an involvement of

sensory afferent input in dystonia and can be observed in up to 70% of patients with cervical dystonia and in lower percentages in other forms of focal dystonia

the sensory trick modifies EMG recruitment, sometimes even before the hand makes contact with the face

Holding the chin or touching the face

Cognitionattention deficit in patients with cervical dystonia

that improves after botulinum toxin treatment, suggesting that this might be a secondary phenomenon related to the distracting effects of dystonic spasms

evidence of little or no alteration of cognitive functions in primary dystonia, and evidence to suggest that the attention deficit and subtle cognitive alterations in some studies may well be related to the distracting effects of abnormal movements and pain.

Sleepsleep impairment may be a feature of primary

dystonia that is independent of the severity of the motor features of the disorder. It is, however, correlated with depression and therefore it is not clear at present if there is a primary sleep abnormality in dystonia

Quality of LifePatients with cervical dystonia seem to be more

severely impaired by pain and depressionThe impact of non-motor symptoms on quality of

life indicates the importance of taking non-motor symptoms into account for clinical assessment and treatment when developing and evaluating new treatments for primary dystonia.

Treatment reports of induction or worsening of dystonia with selective serotonin re-

uptake inhibitors and dopamine receptor antagonist Medications in low doses such as benzodiazepines, baclofen, or

anticholinergic agents are useful in the early stages of CD Intrathecal baclofen at a high cervical level has also been used to treat

hypertonicity Botulinum toxin treatment provides moderate to marked effect on the quality

of life (BoNT/A) = treatment of choice Provides graded, reversible denervation of the NMJ by preventing release of Ach

from presynaptic axons of the motor end plate Average duration of benefit is 12-16 wks

bilateral pallidal deep brain stimulation and selective peripheral denervation is used when a patient has not responded to pharmacological or other interventions Clinical sx should be stable for at least 1 year before surgery is considered DBS to the basal ganglia, thalamus, Gpi and subthalamic nucleus has been noted

Botox injections based on presentation

Torticollis – C/L SCM and ipsilateral trapezium and spleniusLaterocollis – Splenius, trapezium and ipsilateral SCMAnterocollis – B/L SCMRetrocollis – Trapezium and B/L paraspinalis

Recognition of the importance of non-motor symptoms in the clinical picture of primary dystonia may lead the way towards novel targets to improve the movement disorder.

The recognition of the sensory components of dystonia has led some to investigate if manipulating sensory input could be a way to correct primary or secondary abnormalities in sensory representations and improve motor symptoms

Questions?????

ReferencesCervical Dystonia; Camargo et al, Arq Neuropsiquiatr

2008; 66(1)15-21.Cervical Dystonia: Disease Profile and Clinical

Management; Beth E Crowner. Phys Ther. 2007; 87:1511-1526.

The Non-motor Syndrome of Primary Dystonia Clinical and Pathophysiological Implications Maria Stamelou; Mark J. Edwards; Mark Hallett; Kailash P. Bhatia Brain. 2012;135(6):1668-1681.

The Sensory and Motor Representation of Synchronized Oscillations in the Globus Pallidus in Patients with Primary Dystonia; Xuguang Liu et al. Brain (2008), 131, 1562-1573.