What is the diagnosis and treatment for cervical dystonia (CD)?

From the Guidelines

Cervical Dystonia (CD) Diagnosis and Treatment Cervical dystonia is characterized by involuntary contractions of the neck and upper shoulder muscles, resulting in abnormal postures or movements of the neck, shoulders, and head 1.

Diagnosis

The diagnosis of CD is primarily clinical, based on the presence of involuntary muscle contractions in the neck, resulting in abnormal postures and movements.

Treatment

Treatment options for CD include botulinum toxin injections, such as onabotulinumtoxinA (Botox) or incobotulinumtoxinA (Xeomin), administered every 3-4 months, with typical doses ranging from 100-200 units per session 1.

• Other FDA-approved formulations of botulinum neurotoxin, such as AboBoNT-A and rimaBoNT-B, are also effective and should be considered for treatment 1.
• Oral medications, such as trihexyphenidyl (Artane) or clonazepam (Klonopin), may also be used to manage symptoms, although their efficacy is generally lower than that of botulinum toxin injections.
• Nerve-stabilizing agents, such as pregabalin, gabapentin, and duloxetine, may be prescribed for pain management and spasm control as indicated 1. It is recommended that primary care clinicians assess patients for cervical dystonia and refer them to a rehabilitation specialist for comprehensive neuromusculoskeletal management if CD is found 1.

From the FDA Drug Label

Treatment of cervical dystonia with botulinum toxins may weaken neck muscles that serve as accessory muscles of ventilation. Patients treated with botulinum toxin may require immediate medical attention should they develop problems with swallowing, speech or respiratory disorders.

The diagnosis of cervical dystonia (CD) is not explicitly stated in the drug label. The treatment for CD with onabotulinumtoxinA (IM) is mentioned, but the label does not provide a comprehensive treatment plan. Key considerations for treatment with botulinum toxins include:

• Weakening of neck muscles that serve as accessory muscles of ventilation
• Risk of swallowing or breathing difficulties, particularly in patients with pre-existing conditions
• Need for immediate medical attention if problems with swallowing, speech, or respiratory disorders occur 2

From the Research

Diagnosis of Cervical Dystonia (CD)

• Cervical dystonia (CD) is a form of dystonia that involves neck muscles, characterized by sustained involuntary muscle contractions causing twisting and repetitive movements or abnormal posturing 3.
• The diagnosis of CD is based on clinical evaluation, and patients are classified into two groups: primary CD (idiopathic) or secondary CD (symptomatic) 3.
• Primary CD has no identifiable cause, while secondary CD may be caused by central or peripheral trauma, exposure to dopamine receptor antagonists, neurodegenerative disease, and other conditions associated with abnormal functioning of the basal ganglia 3.

Treatment Options for CD

• The most widely used and accepted therapy for CD is local intramuscular injections of botulinum toxin (BoNT) type A 3, 4.
• BoNT is effective in reducing dystonic symptoms, pain, and improving quality of life in patients with CD 5, 6.
• Other treatment options include supportive therapy, physical therapy, pharmacotherapy (e.g., anticholinergics, dopaminergic depleting and blocking agents), and surgical therapy (e.g., deep brain stimulation) 3, 7.
• IncobotulinumtoxinA (Xeomin®) is a BoNT/A agent that has been shown to be safe and effective for the treatment of CD, with a lower risk of immunogenicity compared to other BoNT agents 4.

Botulinum Toxin Treatment

• Botulinum toxin treatment is the first-line recommended treatment for CD, with a response rate of up to 90% of patients 6.
• The treatment involves injecting the affected muscles with BoNT, with repeated injections every 3 to 6 months based on individual response duration 7.
• BoNT treatment has been shown to improve pain, dystonic symptoms, and quality of life in patients with CD, although the effect on health-related quality of life is unclear 5.
• Adverse events associated with BoNT treatment are usually mild and self-limiting, including dry mouth, neck weakness, dysphagia, and voice changes 5.