Movement disorders

Movements disorders are divided into three broad categories: hyperkinetic (increased or exaggerated movement), hypokinetic (reduced or slow movement) and a third category dyskinesia, which results in abnormal involuntary movements.

Read more: Tardive dyskinesia

The following conditions come under movement disorders:

• Ataxia: Marked by impaired coordination, ataxia is a degenerative neurological condition in which the part of the brain which controls balance and coordination is affected. This can happen due to damage to the cerebellum, the nerves or the muscles in the body. Some of the features of this condition include slurred speech, falling down frequently and a general lack of coordination. (Read more: Friedreich's ataxia)
• Dystonia: Dystonia is a movement disorder that results in the patient's muscles contracting involuntarily. This causes the affected part of the body to twist abnormally, leading to unusual postures or repetitive movements that are often painful. It is a condition that can either affect a part of the body or the entire body. (Read more: Cervical dystonia)
• Parkinson's disease: The most common of all movement disorders, Parkinson's disease is another degenerative neurological condition that causes tremors, slowing down of movement and difficulty walking.
• Parkinsonism: This condition is a collection of disorders that have similar symptoms to the disease it borrows its name from.
• Huntington's disease: Another degenerative condition, Huntington's disease is usually inherited or genetic. In this condition, the nerves in the brain gradually lose their function - this includes the nerves that control movement in the body. Huntington's usually leads to chorea (involuntary and abrupt movements), a reduction in cognitive ability and other neuropsychiatric conditions.
• Tourette syndrome: Another widely known movement disorder, Tourette syndrome usually causes sudden twitching movements, tics or involuntary sounds. This condition usually appears early on in life, particularly before reaching adulthood.
• Tremors: Another common movement disorder, tremors are usually characterised by twitching, shaking or other involuntary movements that commonly affect the hands, feet, face, head or even voice. (Read more: Hand tremors)
• Multiple system atrophy: A rare movement disorder, multiple system atrophy can affect various bodily functions such as blood pressure, bladder function, motor movements as well as breathing.
• Restless legs syndrome: One of the more common expressions of a movement disorder, restless legs syndrome presents as an uncontrollable urge to move the legs, especially when sitting or lying down. A study by neurologists in Lagos, Nigeria, found a prevalence of about 9,800 people per 100,000 population. A study in South India put the prevalence at about 2.1% among city dwellers.
• Wilson's disease: A rare genetic condition, Wilson's disease is a neurological condition which occurs due to an abnormal build-up of copper in the body.
• Myoclonus: An involuntary movement disorder, myoclonus is often characterised by sudden jerks or contractions in the muscles. Hiccups are considered to be a type of myoclonus. Current medical opinion is that myoclonus doesn't usually cause any problems and is not related to any underlying condition.(Read more: Muscle cramps)
• Startle syndromes: An involuntary response to a sudden stimulus, a startle response could be vocal or physical. Startle syndromes encompass different conditions, including rare ones like hyperekplexia and Jumping Frenchmen of Maine. Some non-epileptic disorders are also categorised under this syndrome.

Though sudden involuntary movements are the common factor, the symptoms of movement disorders can vary depending on the underlying condition:

• Loss of coordination in the case of ataxia
• Involuntary contraction of the muscles in the case of dystonia
• The wasting away or degradation of nerve cells in Huntington's disease
• Tremors that cause jerking, shaking or trembling in different parts of the body
• Sudden twitches in movement or sounds, also known as tics
• The slowing down of movement or difficulty in walking like in the case of Parkinson's disease

The following may cause movement disorders:

• Brain injury, spinal cord injury, damage to the peripheral nerves
• Sudden brain condition such as stroke or vascular diseases (read more: Peripheral vascular disease)
• Infections
• Genetics: Some movement disorders are hereditary and passed on from either parent
• Certain medications are also known to cause movement disorders. For example, anti-convulsants used in the treatment of epilepsy and some bronchodilators used in asthma can cause tremors
• Metabolic disorders
• Toxins

Movement disorders are neurological conditions that can often be confused with another condition that has similar symptoms. To accurately diagnose the condition, other similar disorders must be ruled out.

The doctor will ask about the patient's medical history and symptoms. Next, he or she will perform a physical exam to assess the neurological functions. This exam may include checking the patient's reflexes and motor skills.

The doctor may also order some tests based on the symptoms and findings during the physical exam. These may include:

• Blood tests
• Cerebral spinal fluid test
• EMG or electromyography, a test performed to test the electrical impulses in the nerves and muscles
• EEG or an electroencephalogram that reads the functioning of the brain
• An ECG or electrocardiogram to check if problems in the heart are causing the symptoms
• MRI or CT scans to look for atrophy (wasting or thinning) in the brain, or blood clots or bleeding inside the brain
• Cerebral angiography, to examine the blood vessels in the head and neck. This test is conducted if MRI or CT scans show any activity that needs to be looked at in more detail

Many of the movement disorders mentioned above cannot be cured and thus treatment often includes clinical management to reduce the appearance of symptoms or any pain being caused by the underlying condition.

The treatment depends on the underlying condition.

Some conditions are degenerative and worsen with age and over time, and can result in the permanent impairment of movement or speech.

Early diagnosis can often help in slowing the progression of some types of movement disorders. Some disorders or their symptoms can be managed or slowed down with the help of medications, while physical therapy or occupational therapy can also help in maintaining the range of movement or restore function in the affected part of the body.

Muscle contractions are usually controlled through specific injections that can prevent the sudden onset of symptoms and the resulting pain.

In some cases, surgically inserting an implant to stimulate the part of the brain that manages movement in the body may help.