The bones and joints of the human body, although designed to withstand a great deal of stress, are subject to a variety of disorders that can affect people of all ages. Some skeletal deformities are the result of congenital defects, and can be treated by physical therapy or surgery with varying degrees of success.
Arthritis is probably the most common of all disabling diseases, at least in the temperate areas of the world. It has been estimated that almost 20 percent of the population suffers from one of the many forms of arthritis.
When looked at from the side, the normal human spine follows a shallow S-shaped curve. If there is an exaggerated forward curvature of the spine, that condition is described as a lordosis.
Because bone consists of living cells, it is constantly changing as old cells die and new cells take their places. Any systemic disease during the growing period may temporarily halt the growth of long bones.
Bones can be broken or displaced when the body is subjected to a violent impact or when a limb is suddenly wrenched out of its normal position. Auto and bicycle accidents and accidents in and around the home account for many such injuries.
If any part of the brain has developed abnormally, the usual function of that structure would be expected to be altered. Abnormalities present at birth are called congenital defects.
It's called the river of life, the five or six quarts of blood that stream through the 60,000 tortuous miles of arteries, veins, and capillaries.
Diseases of the blood vessels are the result primarily of adverse changes in the vessel walls, such as hardening of the arteries, stroke, and varicose veins.
HHeart disease is the commonly used, catch-all phrase for a number of disorders affecting both the heart and blood vessels. A more apt term is cardiovascular disease, which represents America's worst health scourge.
The function of the digestive system is to accept food and water through the mouth, to break down the food's chemical structure so that its nutrients can be absorbed into the body, a process called digestion, and to expel undigested particles. This process takes place as the food passes through the entire alimentary tract.
The human body cannot survive for more than a very few minutes in an environment that lacks oxygen. Oxygen is required for the normal functioning of all living body cells.
Two present-day problems of major proportions are not diseases in themselves, but both are detrimental to health. These are smoking and air pollution.
Glands are organs that produce and secrete substances essential for normal body functioning. There are two main types of glands: the endocrine and the exocrine.
The immune system is what protects us from different types of disease. When an invading bacteria, virus, or other antigen enters the human body, a network of cells move in to attack and destroy the invading substance.
Autoimmune diseases are created when the human body stops recognizing one internal part as its own. It fails to recognize the “self cells and attacks them as if they were foreign bodies.
Most people never experience any impairment of the senses of smell, taste, and touch. But it is indeed lucky and unusual to reach old age without having some problems connected with sight or with hearing or both.
The parts of the urinogenital tract that produce and get rid of urine are the same for men and women: the kidneys, ureters, bladder, and urethra. To understand some of the problems that can arise from diseases of the urinary tract, it is necessary to know a few facts about the anatomy and function of these parts.
Cancer has always figured uniquely in the diseases of mankind. For centuries people spoke of it only in whispers, or not at all, as if the disease were not only dreadful but somehow shameful as well.
This chapter discusses a number of diseases of major importance that are not dealt with elsewhere: acquired immune deficiency syndrome (AIDS), a disease characterized by a defect in the body's natural immune system; plague, of great historical importance but fortunately now uncommon in the United States; three infectious diseases—Hantavirus, tularemia and Rocky Mountain Spotted Fever; and seven tropical diseases that afflict millions of people in the warmer regions of the world and that occasionally occur elsewhere—malaria and yellow fever, leishmaniasis, trypanosomiasis, filariasis, schistosomiasis, and leprosy.