What Is Cervical Dystonia, A Quick Refresher

What is Cervical Dystonia?

Dystonia refers to a sustained, involuntary muscle contraction that causes abnormal movements. Cervical dystonia (CD), also known as spasmodic torticollis, is the most common form of focal dystonia. Patients may exhibit sustained or jerky movements of the cervical musculature and awkward posturing of the head, neck, and shoulders. CD is more prevalent in women and more than 70% of known cases occurs between the fourth and sixth decades of life, peaking in the fifth decade. Due to varying presentations of the disease, it has been frequently misdiagnosed and appropriate therapeutic treatments are often delayed.

Causes

The reason behind cervical dystonia is not well understood. It is generally believed to be an abnormality in central motor neuron processing. Other factors that may contribute to the development or progression of the disease include:

1. Genetic factors;
2. Trauma;
3. Altered sensory input;
4. Primary vestibular abnormality;
5. Impaired basal ganglia functioning.

Signs and Symptoms

Clinical features depend on the severity of the disease, the muscles involved, and the head positioning assumed. The characteristic trait of cervical dystonia is the involvement of “geste antagoniste.” The majority of patients find temporary relief from symptoms through certain tricks. An example of this is gently touching the face or neck; this action reduces muscle spasm, allowing the head to return to its normal position. It is unclear how sensory tricks work, but they tend to lose effectiveness as the disease progresses.

Early manifestations:

1. Head tremors
2. Neck spasms
3. Abnormal head posture

Other symptoms:

1. Neck pain
2. Head twisting
3. Head jerking
4. Headache

Classification of Cervical Dystonia

Based on etiology:

1. Idiopathic or primary cervical dystonia—occurring without other neurological symptoms or pathological abnormalities
2. Secondary cervical dystonia—occurring with other neurologic disorders such as brain lesions and trauma.

Based on dominant head position:

1. Torticollis – head twisting (most common type)
2. Laterocollis – lateral head tilt
3. Retrocollis – backward head tilt
4. Anterocollis – forward flexion of the neck

Treatment

There is currently no cure for dystonia, but the introduction of botulinum toxin has improved CD treatment modalities substantially.

Drugs – Oral pharmacologic therapy, when combined with Botox, showed satisfactory results. Oral medication commonly used to manage CD symptoms are:

1. Anticholinergic agents;
2. GABA (gamma-aminobutyric acid) mimetic agents;
3. Dopamine depleting agents;
4. Dopamine receptor agonists.

Surgery – For patients that are unresponsive to botulinum toxins or combination therapies. A number of patients may experience spontaneous remission; hence, this procedure must be reserved for those who have the disease longer than 1 year.

Relaxation therapies – Includes behavior therapy, hypnosis, meditation, and electromyographic (EMG) biofeedback. They are found to be effective in some cases.

Botulinum Toxin (BT) Therapy – Detailed information about CD therapy with Botox and other botulinums here.