Paralysis (redirected from paralyse)

Paralysis 

Definition

Paralysis is defined as complete loss of strength in an affected limb or muscle group.

Description

The chain of nerve cells that runs from the brain through the spinal cord out to the muscle is called the motor pathway. Normal muscle function requires intact connections all along this motor pathway. Damage at any point reduces the brain's ability to control the muscle's movements. This reduced efficiency causes weakness, also called paresis. Complete loss of communication prevents any willed movement at all. This lack of control is called paralysis. Certain inherited abnormalities in muscle cause periodic paralysis, in which the weakness comes and goes.

The line between weakness and paralysis is not absolute. A condition causing weakness may progress to paralysis. On the other hand, strength may be restored to a paralyzed limb. Nerve regeneration or regrowth is one way in which strength can return to a paralyzed muscle. Paralysis almost always causes a change in muscle tone. Paralyzed muscle may be flaccid, flabby, and without appreciable tone, or it may be spastic, tight, and with abnormally high tone that increases when the muscle is moved.

Paralysis may affect an individual muscle, but it usually affects an entire body region. The distribution of weakness is an important clue to the location of the nerve damage that is causing the paralysis. Words describing the distribution of paralysis use the suffix "-plegia," from the Greek word for "stroke." The types of paralysis are classified by region:

Causes and symptoms

Causes

The nerve damage that causes paralysis may be in the brain or spinal cord (the central nervous system) or it may be in the nerves outside the spinal cord (the peripheral nervous system). The most common causes of damage to the brain are:

Damage to the spinal cord is most often caused by trauma, such as a fall or a car crash. Other conditions that may damage nerves within or immediately adjacent to the spine include:

Damage to peripheral nerves may be caused by:

Symptoms

The distribution of paralysis offers important clues to the site of nerve damage. Hemiplegia is almost always caused by brain damage on the side opposite the paralysis, often from a stroke. Paraplegia occurs after injury to the lower spinal cord, and quadriplegia occurs after damage to the upper spinal cord at the level of the shoulders or higher (the nerves controlling the arms leave the spine at that level). Diplegia usually indicates brain damage, most often from cerebral palsy. Monoplegia may be caused by isolated damage to either the central or the peripheral nervous system. Weakness or paralysis that occurs only in the arms and legs may indicate demyelinating disease. Fluctuating symptoms in different parts of the body may be caused by multiple sclerosis.

Sudden paralysis is most often caused by injury or stroke. Spreading paralysis may indicate degenerative disease, inflammatory disease such as Guillain-Barré syndrome or CIDP, metabolic disorders, or inherited demyelinating disease.

Other symptoms often accompany paralysis from any cause. These symptoms may include numbness and tingling, pain, changes in vision, difficulties with speech, or problems with balance. Spinal cord injury often causes loss of function in the bladder, bowel, and sexual organs. High spinal cord injuries may cause difficulties in breathing.

Diagnosis

Careful attention should be paid to any events in the patient's history that might reveal the cause of the paralysis. The examiner should look for incidents such as falls or other traumas, exposure to toxins, recent infections or surgery, unexplained headache, preexisting metabolic disease, and family history of weakness or other neurologic conditions. A neurologic examination tests strength, reflexes, and sensation in the affected area and normal areas.

Imaging studies, including computed tomography scans (CT scans), magnetic resonance imaging (MRI) scans, or myelography may reveal the site of the injury. Electromyography and nerve conduction velocity tests are performed to test the function of the muscles and peripheral nerves.

Treatment

The only treatment for paralysis is to treat its underlying cause. The loss of function caused by long-term paralysis can be treated through a comprehensive rehabilitation program. Rehabilitation includes:

Prognosis

The likelihood of recovery from paralysis depends on what is causing it and how much damage has been done to the nervous system.

Prevention

Prevention of paralysis depends on prevention of the underlying causes. Risk of stroke can be reduced by controlling high blood pressure and cholesterol levels. Seatbelts, air bags, and helmets reduce the risk of injury from motor vehicle accidents and falls. Good prenatal care can help prevent premature birth, which is a common cause of cerebral palsy.

Resources

Books

Bradley, Walter G., et al., editors. Neurology in Clinical Practice. 2nd ed. Boston: Butterworth-Heinemann, 1996.

Key terms

Computed tomography (CT) — An imaging technique in which cross-sectional x rays of the body are compiled to create a three-dimensional image of the body's internal structures.

Electromyography — A test that uses electrodes to record the electrical activity of muscle. The information gathered is used to diagnose neuromuscular disorders.

Magnetic resonance imaging (MRI) — An imaging technique that uses a large circular magnet and radio waves to generate signals from atoms in the body. These signals are used to construct images of internal structures.

Myelin — The insulation covering nerve cells. Demyelinating disease causes a breakdown of myelin.

Myelography — An x-ray process that uses a dye or contrast medium injected into the space around the spine.

Nerve conduction velocity test — A test that measures the time it takes a nerve impulse to travel a specific distance over the nerve after electronic stimulation.

---

paralysis /pa·ral·y·sis/ (pah-ral´i-sis) pl. paral´yses   loss or impairment of motor function in a part due to lesion of the neural or muscular mechanism; also, by analogy, impairment of sensory function (sensory p.) .

---

paralysis a´gitans  Parkinson's disease.

ascending paralysis  spinal paralysis that progresses cephalad.

bulbar paralysis  progressive bulbar palsy.

compression paralysis  that caused by pressure on a nerve.

conjugate paralysis  loss of ability to perform some parallel ocular movements.

crossed paralysis , cruciate paralysis that affecting one side of the face and the other side of the body.

decubitus paralysis  that due to pressure on a nerve from lying for a long time in one position.

divers' paralysis  decompression sickness.

Duchenne's paralysis 

1. Erb-Duchenne p.

2. progressive bulbar palsy.

Erb-Duchenne paralysis  paralysis of the upper roots of the brachial plexus, caused by birth injury.

facial paralysis  weakening or paralysis of the facial nerve, as in Bell's palsy.

familial periodic paralysis  a rare inherited disorder with recurring attacks of rapidly progressive flaccid paralysis associated with serum potassium levels that are decreased (type I or hypokalemic type), increased (type II or hyperkalemic type), or normal (type III or normokalemic type).

hyperkalemic periodic paralysis  see familial periodic p.

hypokalemic periodic paralysis  see familial periodic p.

immune paralysis , immunologic paralysis older name for immunologic tolerance.

juvenile paralysis agitans (of Hunt)  increased muscle tonus with the characteristic attitude and facies of paralysis agitans, occurring in early life and due to progressive degeneration of the globus pallidus.

Klumpke's paralysis , Klumpke-Dejerine paralysis lower brachial plexus paralysis caused by birth injury, particularly during a breech delivery.

Landry's paralysis  acute idiopathic polyneuritis.

mixed paralysis  combined motor and sensory paralysis.

motor paralysis  paralysis of voluntary muscles.

musculospiral paralysis  paralysis of the extensor muscles of the wrist and fingers.

normokalemic periodic paralysis  see familial periodic p.

periodic paralysis 

1. any of various diseases characterized by episodic flaccid paralysis or muscular weakness.

2. familial periodic p.

postepileptic paralysis  Todd's p.

progressive bulbar paralysis  see under palsy.

pseudobulbar paralysis  spastic weakness of the muscles innervated by the cranial nerves, i.e., the facial muscles, pharynx, and tongue, due to bilateral lesions of the corticospinal tract, often accompanied by uncontrolled weeping or laughing.

pseudohypertrophic muscular paralysis  see under dystrophy.

sensory paralysis  loss of sensation due to a morbid process.

thyrotoxic periodic paralysis  recurrent episodes of generalized or local paralysis accompanied by hypokalemia, occurring in association with Graves' disease, especially after exercise or a high carbohydrate or high sodium meal.

Todd's paralysis  transient hemiplegia or monoplegia after an epileptic seizure.

vasomotor paralysis  cessation of vasomotor control.

---

pa·ral·y·sis (p-rl-ss)

n. pl. pa·ral·y·ses (-sz)

1. Loss of power of voluntary movement in a muscle through injury or through disease of its nerve supply.

2. Loss of sensation over a region of the body.

---

paralysis (pral´isis),

n 1. the cessation of cell function.
n 2. the loss or impairment of the motor control or function of a part or region.

paralysis, diplegia

n a loss of motor function in matching body parts (e.g., legs) on each side.

paralysis, facial,

n paralysis of the muscles of facial expression resulting from supranuclear, nuclear, or peripheral nerve disease. With a mild case, when the face is at rest, the disorder is not readily observed. However, during muscular contraction (e.g., wrinkling the forehead, blinking the eyes, pursing the lips, speaking), the disorder is very noticeable. Only one lid may close, and the asymmetry of the oral cavity is pronounced because the normal buccinator muscle contracts and is unopposed by the weakness on the paralyzed side. This imbalance produces a significant asymmetry. The affected side remains smooth, and the normal side shows contraction. See also palsy, Bell's.

paralysis, infantile,

n See poliomyelitis.

paralysis, motor,

n a loss of the power of skeletal muscle contraction, resulting from interruption of some part of the pathway from the cerebrum to the muscle.

paralysis, transient,

n the sudden loss of sensation or ability to move on one side or a single part of the body, which lasts briefly and may or may not recur and is often a symptom of cerebrovascular insufficiency or other underlying serious condition.

paralysis, transient facial,

n a temporary unilateral loss of facial muscle function as a result of inadvertently injecting the parotid gland containing the facial nerve during the inferior nerve block.

---

paralysis

loss or impairment of motor function in a part due to a lesion of the neural or muscular mechanism; also, by analogy, impairment of sensory function (sensory paralysis). Called also palsy. Motor paralysis may be expressed as flaccid, in the case of lower motor neuron lesion, or spastic, in the case of an upper motor neuron lesion. See also paraplegia, quadriplegia, hemiplegia and paralyses of individual cranial and peripheral nerves.

---

paralysis of accommodation

paralysis of the ciliary muscles of the eye so as to prevent accommodation.

anal paralysis

manifested by flaccidity and lack of tone of the anal sphincter, and loss of house training restraint in companion animals.

antepartum paralysis

pressure on sciatic nerves by a large fetus in late pregnancy in a cow can cause posterior paralysis that is cured by a cesarean section.

ascending paralysis

spinal paralysis that progresses forwards involving first the hindlimbs then the forelimbs, then the intercostal muscles, then the diaphragm, and finally the muscles of the neck.

birth paralysis

that due to injury received by the neonate at birth.

bladder paralysis

manifested by fullness of the bladder and response to manual pressure. See also motor paralytic urinary bladder.

cage paralysis

see thiamin nutritional deficiency.

central paralysis

any paralysis due to a lesion of the brain or spinal cord.

cerebral paralysis

paralysis caused by some intracranial lesion.

Chastek paralysis

see thiamin nutritional deficiency.

compression paralysis

that caused by pressure on a nerve.

congenital paralysis

paralysis of the newborn. Many cases are due to birth trauma especially when lay persons exert excessive traction. Other causes are enzootic ataxia, inherited congenital paraplegias in calves and pigs, spina bifida and spinal dysraphism and occipito-alanto-axial malformations in foals and puppies.

conjugate paralysis

loss of ability to perform some parallel ocular movements.

coonhound paralysis

see idiopathic polyradiculoneuritis.

crossed paralysis

paralysis affecting one side of the head and the other side of the body.

curled toe paralysis

a disease of poultry caused by a nutritional deficiency of riboflavin. See also curled toe paralysis.

decubitus paralysis

paralysis due to pressure on a nerve from lying for a long time in one position.

esophageal paralysis

manifested by inability to swallow, and regurgitation.

facial paralysis

weakening or paralysis of the facial nerve. See also facial paralysis.

flaccid paralysis

paralysis characterized by loss of voluntary movement, decreased tone of limb muscles, absence of tendon reflexes and neurogenic atrophy.

immunological paralysis

the absence of immune response to a specific antigen. See also tolerance.

infectious bulbar paralysis

see aujeszky's disease.

ischemic paralysis

local paralysis due to stoppage of circulation.

lambing paralysis

maternal obstetric paralysis in the ewe.

laryngeal paralysis

see laryngeal hemiplegia.

mixed paralysis

combined motor and sensory paralysis.

motor paralysis

paralysis of the voluntary muscles.

nerve paralysis

paralysis caused by damage to the local motor nerve supply. See also peripheral nerve paralysis (below).

obstetric paralysis

see maternal obstetric paralysis.

partial paralysis

see paresis.

peripheral nerve paralysis

the part deprived of its peripheral nerve supply shows flaccid paralysis, absence of spinal reflexes, muscle atrophy and a subnormal temperature.

postcalving paralysis

see maternal obstetric paralysis.

posterior paralysis

paralysis of the hindlimbs, tail and perineum. See also paraplegia.

range paralysis

see marek's disease.

sensory paralysis

loss of sensation resulting from a morbid process.

spastic paralysis

paralysis with rigidity of the muscles and heightened deep muscle reflexes.

tongue paralysis

see hypoglossal nerve paralysis.