Movement Disorder

 Movement Disorder

    PKGhatak, MD

Muscles move joints and joints move the body. Movement does not only refer to ambulatory movements but movements of part of the body when the person is stationary. In any movement, two groups of muscles work in a coordinated manner, one group contacts the other group must stay in a relaxed state for the movement to occur. If both groups contact simultaneously, the joint is held in a fixed position and is called spasm.

Well known Movement disorders:

Parkinson's disease, Parkinson syndrome, tremors, ataxia, chorea, tics, myoclonus and spasticity.

Parkinson's Disease (PD) and Parkinson Syndrome:

Parkinson's disease is due to the sickness of Dopamine (neurotransmitter) producing cells located in the Substantia nigra in the hindbrain. Slowly the cells die and many neurological abnormalities develop, including dementia and psychosis.

Movement abnormality in PD.

Slow movement and lack of associated movements, like swinging of arms while walking, are striking features. Increased muscle rigidity of neck, head, limbs and back muscles produces a stooping forward posture; and stiffness of legs and thighs produces a shuffling gait. Tremors of hands at rest produce pill-rolling movement of fingers; later writing, feeding, and grooming become difficult. Loss of balance causes frequent falls. The cause of PD is unknown.

Parkinson Syndrome. This term is reserved for Parkinson like features in patients with known causes, for example - poisoning from heavy metals and pesticides, repeated cerebral concussion, and adverse effects of drugs used in Psychosis, Schizophrenia, Depression, etc.

Parkinson's disease (PD) Subtypes.

Experts classify the movement abnormalities in two catigories.1. Tremor predominant. 2. Postural instability - gait difficulties.

1. Tremor-predominant.

Clinically tremor-predominant PD are of three kinds- Mild, Progressive malignant and intermediate varieties.

a. Mild.

Tremors are mostly seen while trying to work with hands.

B. Progressive malignant PD tremors.

Tremors are rapidly progressive type. The resting tremors are present during waking hours and in light sleep but during deep sleep, tremors disappear. Tremors prevent patients from doing most routine work - like cooking, cleaning, or answering telephone calls.

C. Intermediate

The symptoms of this subtype fall between the above two subtypes.

2. Postural instability-gait difficulty.

Due to increased rigidity, the patients assume a stooping posture. There is a lack of spontaneous corrective adjustments of posture. Decreased two-way communication with the cerebellum produces unsteady balance and a slight bump against a chair or wall the patient falls forward on the ground.

Subtypes of Parkinson's disease.

A. Progressive Supranuclear Palsy (PSP).

The most distinctive feature of PSP is recurrent sudden backward fall on attempted walking, however, during and after the fall the patient remains fully conscious.  Pseudobulbar palsy leads to difficulty in chewing and swallowing. Intranuclear ophthalmoplegia produces abnormal eye conjugate movements when looking downwards. The patient is unable to look upwards and on attempts to look upward produce horizontal nystagmus. The upper eyelids are kept half-closed. PSP patients have no rigidity and tremors unless the disease is far advanced.

B. Restless Leg Syndrome (RLS).

Patients develop an uncontrollable urge to move. Symptoms may be intermittent, and the degree may vary. Restlessness may also be felt in the arms, neck and head. Sitting on a chair for a long period, driving an automobile and sleeping at night become difficult. Patients also describe a strange sensation of insects crawling under the skin, pins and needles, throbbing and aching pain deep in the legs and lower body.

The use of Dopaminergic drugs -  Pramipexole, Ropinirole and Rotigotin  produce some relief in the early phase of the disease. Later L-dopa may be helpful.

C. Lewy body dementia.

Abnormal muscle movements are generally periodic, bizarre, uncontrollable and purposeless. Apathy and profound loss of memory lead to total dependence on others for activities of daily living.

Other Neurological Conditions.

Neurological conditions produce muscle disorders, for example, Multiple System Atrophy (MSP), Cortico-Bulbar syndrome, Low pressure hydrocephalous, Huntington disease, Wilson disease, Tourette syndrome, Motor stereotypies and Multi System Atrophy.

Multi System Atrophy. 

The impairment of the autonomic nervous system produces a loss of spontaneous adjustment of BP with postural changes and with physical activities. Postural hypotension is common. Of the GI symptoms constipation and difficulty in swallowing are common. Men may develop erectile dysfunction and difficulty in voiding urine. Olivopontocerebellar atrophy produces stiffness and incoordination of movements. loss of balance and slowness of movements.

Corticobulbar syndrome.

Degeneration of neurons in the motor and sensory cortex produces symptoms of poor muscle coordination, slowness of thought processing, language difficulty and speech abnormality. Increased and prolonged increased muscle tome produces stiffness of posture.

Huntington disease.

Huntington disease is an autosomal dominant inherited condition. Progressive severe dementia, obsessive compulsive disorder, mania, and bipolar disorder are major components. Writhing slow dance like movements, jerky movements of limbs, (called Chorea) language and speech abnormalities are present. Slow eye movements, muscle rigidity, impaired gait, balance and posture resemble PD. 

Wilson disease. It is a recessive mode of inherited disease involving excess copper accumulation in the brain and other vital organs. The muscle disorder includes tremors, difficulty in swallowing and speech and trouble in ambulation. Cirrhosis of the liver at an advanced stage is common. Copper accumulation at the periphery of the cornea of the eye produces a distinct diagnostic feature called the Kaiser Flacherie ring.

Tourette syndrome. It is an inherited disease, but the precise genetic abnormality is not known. Involuntary movements commonly involve the face and uncontrollable vocal sounds followed by the arms, legs, or trunk. Vocalizations of embarrassing words called Coprolalia often accompanied by obscene jesters, Copropraxia, make patients difficult to socialize with. The symptoms usually begin in childhood and spontaneously may disappear when older.

Motor stereotypes.

These are fixed repeated movements with no useful purpose, appear at the same predictable location and time. Movements last a minute or longer and occur several times a day. Typical motor stereotypes are thumb sucking, lip biting, hair twirling, teeth grinding and head banging. Symptoms start in childhood and rarely persist in adult life. Sometimes more complex motor dysfunctions involving hand and arm movements like waving arms and wiggling fingers in front of the face and closing and opening hands.

Essential tremors. In this disorder, rhythmic involuntary fine shaking movements of hands generally appear in midlife. Tremors mostly occur when the patient is in the company of others and performing normal tasks like drinking a cup of coffee or buttoning a shirt. Tremors may also happen in the head producing nodding of the head as yes-yes or no- no jesters.

Spasticity. Prolonged muscle contractions lead to increased tone of muscles that interfere with normal walking or performing activities of daily living. Spasticity is a feature of cerebral stroke, Multiple sclerosis, spinal cord injury, spina bifida and severe brain injury.

Dystonia. Dystonia is an involuntary muscle spasm producing twisting motion of the limbs or trunk producing abnormal posture and positions. An example is Writer's cramp. The onset of dystonia is gradual and always follows a specific muscle action. Muscles fail to relax in between contractions preventing smooth functioning.

Ataxia. Ataxia means uncoordinated muscle actions, mostly noticeable in arms and legs. Cerebellar ataxia is more common. In the younger age group, viral infections, tumors and cysts and vascular disruption in elderly people are common causes.

Tardive Dyskinesia (TD). Tardive means late onset. Dyskinesia is defined as difficulty in performing voluntary functions. Muscles of the face, tongue and upper extremity show repeated involuntary movements like grimacing, lip smacking, pursing of lips, eye blinking, and rapid involuntary arm, torso and finger movements. Long term use of anti-Schizophrenia, Anti choline and anti-depression drugs use are associated with TD. Discontinuation of drugs improves symptoms if done early.

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