Essential Tremor

Essential tremor (ET) is one of the most common movement disorders.

It typically involves a tremor of the arms, hands or fingers but sometimes may involve the head, vocal cords or other body parts during movements such as eating and writing.

It usually occurs in people who are 40 or above. Although the exact cause of ET is not known, it is believed to run in families.

Curently there is no cure for essential tremor.

The main symptoms of essential tremor include:

• Uncontrollable shaking that occurs for brief periods of time
• A shaky voice
• Noddind head
• Tremors that worsen during periods of emotional stress and purposeful movements
• Tremors that lessen with rest
• Problems with balance

The uncontrollable movements seen in ET are also seen in other diseases like Parkinson's disease and multiple sclerosis.

However,the tremors seen in ET occur mostly when a person is using his/her hands and ET, unlike Parkinson's disease or multiple sclerosis does not cause other health problems.

Although the true cause of essential tremor is not known, it is thought that it is as a result of the abnormal electrical activities of the brain.

These electrical activities are processed through the thalamus, which is a part of the brain that coordinates and controls muscle activity.

Genetics have been shown to be responsible for causing ET in almost 50% of people with this condition.

Therefore, a parent who has ET has a 50% chance of passing it to his or her child. In some cases the child may never experience any symproms.

A diagnosis of essential tremor is usually made based on the symptoms that are reported by the patient and by a complete neurological exam.

A neurological exam checks the function of the nervous system.

The following are checked: tendon reflexes, muscle strength and tone, ability to feel certain sensations, posture, coordination and gait.

Performance tests can also be done to evaluate the tremor.

Blood tests can also be carried out to check for other conditions like thyroid disease and other metabolic disorders.

There is no cure for essential tremor and in mild cases, essential tremor does not require treatment. However, if it interferes with a person's day-to-day activities then treatment becomes necessary.

Two treatment options are availabe:

• medications,
• surgery.

Medications include drugs that reduce the severity of essential tremor such as Mysolin and Neurotin which are anti-seizure drugs.

• Beta blockers such as propranolol have been shown to relieve some symptoms of ET in some people.
• Botox injections can also be given since they have proven to be effective for vocal and head tremors.

A surgical procedure called deep brain simulation (DBS), is usually performed when therapy with drugs fails. In this procedure, electrical leads are implanted into the thalamus, this helps the thalamus to better control muscle movements.

Currently there is no known way to prevent essential tremors since the exact cause is not known.

There are several risks and complications associated with essential tremor.

Some possible risk factors for essential tremor include:

• autosomal dominant inheritance pattern,
• genetic mutations.

The inherited variety of essential tremor (familial tremor) is an autosomal dominant disorder. A defective gene from just one parent is all that it takes for next generation (children of affected parents) to have this condition.If only one parent has a genetic mutation for essential tremor, then children will have a 50 percent chance of developing the disorder.

Essential tremor is more common in people age 40 and older.

Complications often become worse with time. Some reports have linked ET with Parkinson's disease and migrane headaches.