Anoop K. Reddy, MD
Neurologist located in Tampa, FL
Botox Injections for Cervical Dystonia Q & A
Synonyms of Cervical Dystonia
· focal dystoniaidiopathic cervical dystonia
· isolated (formally primary) cervical dystonia
· spasmodic torticollis
· spasmodic wryneck
Cervical dystonia, also known as spasmodic torticollis, is a rare neurological disorder that originates in the brain. It is the most common form of focal dystonia in an office setting. Cervical dystonia is characterized by involuntary muscle contractions in the neck that cause abnormal movements and postures of the neck and head. In some cases, these abnormal contractions may be sustained or continuous; in others, they may be present as spasms that can resemble tremor. The severity of cervical dystonia can vary, but the disorder can cause significant pain and discomfort as well as difficulty due to the abnormal postures. It can affect quality of life and activities of daily living including employment. Cervical dystonia typically begins in middle age, and rarely begins in adolescence and young adulthood. The cause of cervical dystonia is unknown, although a genetic susceptibility is thought to underlie some cases. If cervical dystonia begins in infancy or early childhood, secondary causes should be investigated.
Subtle features of cervical dystonia
Neck pain and tremor are common, but physicians should look for all of these:
· Neck Pain: 89% of patients with cervical dystonia
· Head tremor: 60% of patients with cervical dystonia
· Sensory tricks3,4
· Morning benefit (symptoms are milder in the morning)3
· Tenderness on palpation3
· Exacerbating factors—may be frequent and prominent3
· - Fatigue; stress; observation; motor tasks (eg, driving, walking, or writing)
Signs & Symptoms
The symptoms of cervical dystonia may begin slowly and can involve any of the muscles of the neck. The head posture in cervical dystonia can vary. The most common abnormal posture associated with cervical dystonia is the twisting of the chin toward a shoulder so that the head rotates sideways (torticollis). Other abnormal postures associated with cervical dystonia including anterocollis, in which the head tips forward; retrocollis, in which the head is tilted backward; or laterocollis, in which the head tilts toward one side. There can also be shifting of the head on the shoulders in a forward (anterior sagittal shift) or backward (posterior sagittal shift) direction. Often cervical dystonia is complex and combines several angles of head movement. In some people with isolated CD, there may also be a postural tremor of the hands. Symptoms of cervical dystonia vary over the course of the disorder. Studies of the natural history of CD are needed to better understand the natural history of this disorder. Symptoms may temporarily worsen with stress or excitement. The dystonia can be activated by certain postures or positions. This varies in individual patients. Symptoms may improve with the performance of sensory tricks, such as touching the cheek or the back of the head. A small percentage of individuals experience a spontaneous recovery (remission) after symptom onset. This remission is often temporary, lasting days to years, with recurrence of symptoms. It is likely that less than 1 percent of affected individuals have permanent remissions.
There can be secondary problems arising from cervical dystonia that include cervical spine arthritis, compression of nerve roots, and sometimes narrowing of the spinal cord in the neck (cervical stenosis). Pain related directly to cervical dystonia typically is on the same side as the head turn and is felt as muscular pain in the area of the overactive muscles. Pain can potentially become severe and disabling.
Cervical dystonia is classified as an isolated dystonia if there are no other associated abnormal findings, such as spasticity, Parkinsonism or ataxia. Most isolated cervical dystonia had no identifiable underlying causes. However, in some cases, cervical dystonia can arise from another underlying cause and be considered secondary (occurring as consequence of another disorder or condition). In most cases, isolated cervical dystonia is idiopathic although a genetic susceptibility may be present as evidenced by a positive family history in approximately 10-25% of cases. There are several gene mutations associated with cervical dystonia (GNAL, THAP1, CIZ1, ANO3) and several possible environmental factors. However, at this time there is no gene test that is recommended for clinical purposes in people with cervical dystonia. Some cases of cervical dystonia may have an identifiable cause (secondary cervical dystonia). In these cases, cervical dystonia may develop due to the use of certain drugs such as anti-psychotics or certain nausea medications with dopamine receptor blocking activity, , In most secondary cases, such as those due to toxins or degenerative brain diseases, there are additional signs and symptoms other than cervical dystonia. Whether trauma to the neck could cause cervical dystonia remains controversial. Cervical dystonia is a neurological disorder. However there are some non-neurological conditions that may mimic cervical dystonia. In children with slippage of the vertebrae in the neck (atlanto-axial subluxation), there may be a twisting of the head that is very painful and requires specialized orthopedic treatments. Some infants are born with a shortening of one of the muscles in the neck (congenital infantile torticollis) that causes a head turn. Is some children with esophageal reflux, there can also be posturing of the head. There are additional conditions, including functional movement disorders that may appear similar to cervical dystonia but are non-neurologic in origin.
Cervical dystonia affects women approximately twice as often as men. It is the most common form of focal dystonia in an office setting. Cervical dystonia may affect individuals of any age, but typically develops in people between 40 and 60 years of age. Cervical dystonia affects people of all ethnic backgrounds. The exact incidence or prevalence of cervical dystonia in the general population is unknown but is estimated to be about 60,000 people in the United States.
A diagnosis of cervical dystonia is based upon clinical examination, a detailed patient history, and knowledge of the disorder. No specific laboratory or imaging test confirms a diagnosis of cervical dystonia. There are no abnormalities in laboratory or imaging tests. Magnetic resonance imaging (MRI) of the brain is normal, and MRI of the neck does not help with the diagnosis unless compression of the spinal cord is suspected. Electromyography is not indicated unless there are additional signs of nerve irritation.
Not every treatment option for cervical dystonia is successful for all affected individuals. Therefore, no single strategy is appropriate for every case. Most therapies are symptomatic and are intended to relieve spasms, pain and disturbed postures or functions. Identifying the treatment regimen that is most effective in individual cases may require patience and perseverance on the part of the patient and physician.
There are essentially three treatment options: botulinum toxin injections, oral medications, and, in some cases, surgery. These treatments may be used alone or in combination. In addition, physical therapy may provide a helpful complement to medical treatment. In some cases, if there is a trick such as touching the chin, a soft cervical collar may be beneficial.
Botulinum toxin injections are the treatment of choice for cervical dystonia. Botulinum toxin is a neurotoxin that is injected into the dystonic neck muscles in small doses. Botulinum toxin works by preventing the nerve from releasing a messenger, called acetylcholine, that tells the muscle to contract. This causes weakness of the muscle. The effect of botulinum toxin on the muscle begins approximately 2-3 days following injection, peaks at around 4 weeks, and provides relief for approximately 2-6 months. Botulinum toxin treatment is not a cure, but rather a symptom treatment. When the effect of botulinum toxin wears off, the symptoms of cervical dystonia recur and another injection is needed to sustain benefit. In order for botulinum toxin injections to be successful, it is critical that the injecting physician be well-versed in cervical dystonia, the functional anatomy of the neck muscles, and the type and doses of botulinum toxin to use.
What is Botox?
Botox® is a neurotoxin. Although it’s perhaps most known for its aesthetic uses, it also has a number of medical uses. Doctors will sometimes recommend a Botox® injection for migraines, as well as for an overactive bladder, muscle spasms, muscle stiffness, and excessive sweating.
What Are Botox® Injections?
Botox® injections are a neurotoxin that’s administered via a small shot. Botox® is most widely known among the general population for its uses in aesthetic procedures, but it also has a number of medical uses. Doctors successfully use it to treat everything from overactive bladders to migraine headaches. As a neurotoxin, it’s especially effective at reducing muscle spasms, such as the neck spasms that patients with cervical dystonia experience.
Currently, there are no oral medications that are FDA approved for use in dystonia. Among the oral medications used, dopaminergic agents (levodopa), anticholinergic agents (benztropine, trihexyphenidyl), baclofen and clonazepam are the most frequently used. These drugs are usually most effective in children with generalized dystonia. In adults, the side effects of these agents, including memory problems and sedation, often occur before an effective dose can be reached. Surgical treatments for cervical dystonia are of two types. One is selective peripheral denervation in which the nerves to the dystonic muscles are cut. Although this has been reported to be effective, this approach is limited by the ability to access the nerve involved, the need for considerable expertise of the surgeon, and the potential for side effects. Side effects from the surgery are not uncommon and following surgery, there is a long period of rehabilitation.