Medical Terminology Simplified

434 CHAPTER 9• Endocrine and Nervous Systems

Parkinson disease

PĂR-kĭn-sŭn

Progressive, degenerative neurological disorder affecting the portion of the brain

responsible for controlling movement

The unnecessary skeletal muscle movements of Parkinson disease commonly interfere

with voluntary movement—for example, causing the hand to shake (called tremor), the

most common symptom of Parkinson disease.

Disease in which the gray matter of the spinal cord is destroyed by a slow-acting

virus, eventually leading to paralysis and muscular atrophy

Vaccines have made poliomyelitis, commonly known as polio, relatively uncommon in

the United States. Nevertheless, postpolio syndrome is a complication that develops in

some patients, usually 30 or more years after they are first infected. Muscles that were

already weak may get weaker. Weakness may also develop in muscles that were not

affected before.

Severe pain in the leg along the course of the sciatic nerve, which travels from the hip

to the foot

Abnormal, uncontrolled discharge of electrical activity in the brain, which is

commonly a symptom of underlying brain pathology; also called convulsion

Chronic, recurrent seizures are a characteristic symptom of epilepsy.

Seizure characterized by unconsciousness with excessive motor activity and the body

alternating between excessive muscle tone with rigidity (tonic) and involuntary

muscular contractions (clonic) in the extremities

Tonic-clonic seizures last about 1 to 2 minutes. Other symptoms include tongue biting,

difficulty breathing, and incontinence. The recovery after a seizure is known as the

postictal period.

Seizure characterized by a brief, sudden, loss of consciousness lasting only a few seconds

A person can have many absence seizures during the course of the day.

Eruption of acute, inflammatory, herpetic vesicles on the trunk of the body along a

peripheral nerve

Shingles is caused by the herpes zoster virus.

Congenital neural tube defect characterized by incomplete closure of the spinal canal

through which the spinal cord and meninges may or may not protrude

Spina bifida usually occurs in the lumbosacral area and has several forms. (See Fig. 9–11.)

Most common and least severe form of spina bifida without protrusion of the spinal

cord or meninges

More severe type of spina bifida that involves protrusion of the meninges (meningocele),

spinal cord (myelocele), or both (meningomyelocele).

The severity of neurological dysfunction in spina bifida cystica depends directly on the

degree of nerve involvement.

poliomyelitis

pō-lē-ō-mī-ĕl-Ī-tĭs

poli/o: gray; gray matter

(of the brain or

spinal cord)

myel: bone marrow;

spinal cord

-itis: inflammation

sciatica

sī-ĂT-ĭ-kă

seizure

SĒ-zhūr

tonic-clonic (grand mal)

absence (petit mal)

shingles

SHĬNG-lz

spina bifida

SPĪ-nă BĬF-ĭ-dă

spina bifida occulta

SPĪ-nă BĬF-ĭ-dă ŏ-

KŬL-tă

spina bifida cystica

SPĪ-nă BĬF-ĭ-dă

SĬS-tĭk-ă