Movement Disorder describe a variety of abnormal movements of the body that have a neurological basis. These abnormal movements are characterized by changes in the coordination and speed of voluntary movement. They may also involve the presence of additional movements that are not voluntary.

Causes

Movement disorder originate deep within the central nervous system. They are triggered by changes to specific regions of the brain or nervous system controlling movement. People with a movement disorder suffer from a breakdown in the normal flow of neurological messages and this leads to involuntary muscle movement. They may lose the ability to control these impromptu movements, or to properly coordinate their voluntary movements.

More about the causes of the following movement disorders:

• Parkinson's disease
• Spasticity
• Essential Tremor
• Dystonia

Parkinson's disease

While the exact causes are unknown, we now know that Parkinson's disease develops following a loss of cells in specific parts of the brain. A consensus has emerged that most cases of Parkinson's are caused by a combination of environmental and genetic factors, and that the combination may be different for different people.

Spasticity

• Spasticity can occur when neurological disorders or injuries damage parts of the motor pathways that control voluntary movement. It occurs when muscles receive improper nerve signals and contract - they become tense and short when they should be relaxed or unflexed.
• The most common causes of Spasticity include cerebral palsy, spinal cord injury, multiple sclerosis, stroke, and traumatic brain injuries (such as lack of oxygen, physical trauma, haemorrhage, or infection).
• Spasticity may not be present all the time. It can be brought on by rapid movement or by sensory stimulation. So an important part of both care and treatment is minimizing possible causes of these stimuli, including pain, pressure sores, urinary tract infection, ingrown toenails, restrictive clothing, constipation, and so on.

Essential Tremor

The symptoms of Essential Tremor can begin at any age from childhood through to late adulthood, with an average onset age of about 45 years. The cause of ET is unknown. It may occur sporadically and it can be inherited. In familial (inherited) cases, children of affected people have a 50 percent risk of inheriting the gene for Essential Tremor and eventually developing the disease. However, carrying the ET gene does not always lead to symptoms of tremor. Essential Tremor requires a clinical diagnosis; there is no definitive test. The condition can therefore remain undiagnosed if people delay seeking medical advice for their worsening symptoms. ET is best diagnosed by a movement disorder specialist who has experience with ET patients.

Some of the differences between ET and Parkinson's disease (Pd) are:

• Pd tremors generally occur at rest, whereas ET tremors will occur during activity but be absent when the patient rests.
• Pd patients also exhibit other symptoms, such as slowness and stiffness, while ET patients may only have the tremor symptom.
• Pd medication does not work for people with ET.

Treatment

Treatment for movement disorder depends on the underlying cause. In most cases, the goal of treatment is to relieve symptoms. Treatment may include medication, botulinum toxin injection therapy (BOTOX® therapy), and surgery.

Medications that may be used include the following:

• Antiepileptics (e.g., carbamazepine [Tegretol®], valproate [Depakote®])
• Antiseizure medications (e.g., primidone [Mysoline®], gabapentin [Neurontin®])
• Beta-blockers (e.g., propranolol [Inderal®])
• Dopamine agonists (e.g., bromocriptine [Parlodel®], pergolide [Permax®])
• Tranquilizers (benzodiazepines such as diazepam [Valium®] and clonazepam [Klonopin®])

Side effects of antiepileptics include dizziness, drowsiness, nausea, and vomiting. Antiseizure medications may cause a lack of coordination and balance (ataxia), dizziness, nausea, and fatigue. Benzodiazepines may cause blood clots (thrombosis), drowsiness, and fatigue. Side effects caused by beta-blockers include slowed heart rate (bradycardia), depression, light-headedness, and nausea. Dopamine agonists may cause nausea, headache, dizziness, and fatigue.