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A man goes to the doctor with a long history of migraine headaches. When the doctor does his history and physical, he discovers that his poor patient has had practically every therapy known to man for his migraines and STILL no improvement.
"Listen," says the Doc, "I have migraines too, and the advice I'm going to give you isn't really anything I learned in medical school, but it's advice that I've gotten from my own experience. When I have a migraine, I go home, get in a nice hot bathtub, and soak for a while. Then I have my wife sponge me off with the hottest water I can stand, especially around the forehead. This helps a little. Then I get out of the tub, take her into the bedroom, and even if my head is killing me, I force myself to have sex with her. Almost always, the headache is immediately gone. Now, give it a try, and come back and see me in six weeks."
Six weeks later, the patient returns with a big grin.
"Doc! I took your advice and it works! It REALLY WORKS! I've had migraines for 17 years and this is the FIRST time anyone has ever helped me!"
"Well," says the physician, "I'm glad I could help."
"By the way, Doc," the patient adds, "you have a REALLY nice house."
"Listen," says the Doc, "I have migraines too, and the advice I'm going to give you isn't really anything I learned in medical school, but it's advice that I've gotten from my own experience. When I have a migraine, I go home, get in a nice hot bathtub, and soak for a while. Then I have my wife sponge me off with the hottest water I can stand, especially around the forehead. This helps a little. Then I get out of the tub, take her into the bedroom, and even if my head is killing me, I force myself to have sex with her. Almost always, the headache is immediately gone. Now, give it a try, and come back and see me in six weeks."
Six weeks later, the patient returns with a big grin.
"Doc! I took your advice and it works! It REALLY WORKS! I've had migraines for 17 years and this is the FIRST time anyone has ever helped me!"
"Well," says the physician, "I'm glad I could help."
"By the way, Doc," the patient adds, "you have a REALLY nice house."
The backbone can be divided into five regions, starting with the uppermost, or cervical region, which normally has seven vertebrae. Next down is the thoracic (chest) section, normally with12 vertebrae. From each vertebra a rib extends to curl protectively around the chest area. Usually, the top ten ribs come all the way around the trunk and attach to the breast-bone (or sternum); but the bottom two ribs do not reach the breastbone and thus called floating ribs. The thoracic section also must support the shoulder gridle, consisting of collarbones (clavicles) and shoulder blades (scapulas). At the end of each shoulder blade is a shoulder joint - actually three distinct joints working together - where the arm connects to the axial skeleton.
Below the thoracic vertebrae come the five vertebrae of lumbar section. This area gets a good deal of blame for miseries: lower back pain often occurs around the area where the bottom thoracic vertebra joins the top lumbar vertebra. Furthermore, the lumbar region or small of the back is also a well-know site of back pain; indeed, from the word "lumbar" comes lumbago, medically an imprecise term, but popularly used to describe very real back pain.
Below the lumbar region are two vertebrae so completely different from the 24 above them - and even from each other- that it seems strange they are called vertebrae at all: the sacrum and the coccyx. These two vertebrae are both made up of several distinct vertebrae that are present at birth. The sacrum is a large bone that was once five vertebrae. The coccyx was originally four vertebrae- and, incidentally, is all that remains of man's tail in his evolution from primates.
Below the thoracic vertebrae come the five vertebrae of lumbar section. This area gets a good deal of blame for miseries: lower back pain often occurs around the area where the bottom thoracic vertebra joins the top lumbar vertebra. Furthermore, the lumbar region or small of the back is also a well-know site of back pain; indeed, from the word "lumbar" comes lumbago, medically an imprecise term, but popularly used to describe very real back pain.
Below the lumbar region are two vertebrae so completely different from the 24 above them - and even from each other- that it seems strange they are called vertebrae at all: the sacrum and the coccyx. These two vertebrae are both made up of several distinct vertebrae that are present at birth. The sacrum is a large bone that was once five vertebrae. The coccyx was originally four vertebrae- and, incidentally, is all that remains of man's tail in his evolution from primates.
A man hasn't been feling well, so he goes to his doctor for a complete checkup.
Afterward the doctor comes out with the results.
"I'm afraid I have some very bad news," the doctor says. "You're dying, and you don't have much time left."
"Oh, that's terrible!" says the man. "How long have I got?"
"Ten," the doctor says sadly.
"Ten?" the man asks. "Ten what? Months? Weeks? What?!"
"Nine..."
Afterward the doctor comes out with the results.
"I'm afraid I have some very bad news," the doctor says. "You're dying, and you don't have much time left."
"Oh, that's terrible!" says the man. "How long have I got?"
"Ten," the doctor says sadly.
"Ten?" the man asks. "Ten what? Months? Weeks? What?!"
"Nine..."
Although they will have features in common, no two of our 26 vertebrae are exactly alike in shape, size, or function. This is hardly surprising if we consider, for example, that the cervical vertebrae do not supports ribs, while the thoracic vertebrae (upper trunk, or chest) do support them.
But for a sample vertebra, let us pick a rib-carrying vertebra, if for no other reason than that it lies about midway along the backbone. If viewed from above or below, a thoracic vertebra, like most of the others, would look like a roundish piece of bone with roughly scalloped edges on the side facing outward toward the surface of the back, and would reveal several bony projections. These knobby portions of a vertebra- some of which you can feel as bumps along your backbone- are called processes. They serve as the vertebra's points of connection to muscles and tendons, to ribs, and to other vertebrae above and below.
A further conspicuous feature is a hole, more or less in the middle of the typical vertebra, through which passes the master nerve bundle of our bodies, the spinal cord, running from the base if the skull to the top of the pelvis. thus, one of the important functions of the backbone is to provide flexible, protective tubing for the spinal cord.
Between the bones of one vertebra and the next is a piece of more resilient cartilage that acts as a cushion or shock absorber to prevent two or vertebrae from scraping or bumping each other if the backbone gets a sudden jolt, or as the backbone twist and turns and bends. these pieces of cartilage are the inter vertebral disk- infamous for pain and misery if they become ruptured or slipped disks.
At the base of the skull, the backbone begins. The skull is supported by the topmost cervical (neck) vertebra. The curious thing about a backbone is that the word has come to suggest something solid, straight, and unbending.
The back, however, just isn't like that: it consists of 26 knobby, hollowed-out bones- vertebrae, rather improbably held together by muscles, ligaments, and tendons. Is is not straight when we stand, but has definite backward and forward curvatures; and even some of its most important structures (the disk between the vertebrae) aren't made of bone, but of cartilage.
All in all, however, the backbone is fairly well designed structure in term of several different functions it serves- but with some built-in weaknesses.
The next post will further explain about The Vertebrae.
The hardest substance in the human body is the enamel that covers the exposed surface of a tooth. Below the gum, the tooth's outside surface is composed of somewhat softer cementum. Beneath enamel and cementum is a bonelike substance, call dentin, which covers the soft interior of the tooth, called pulp. Pulp is serviced by blood vessels and nerves through the root or roots of the tooth. The passageway of nerves and blood vessels that lead up through the tooth from the gum sockets is called a root canal. Tooth and gum are stuck to each other by a tough, adhesive tissue called periodontal (or peridental- "surrounding the tooth") membrane.
The bones of the skull have as their most important function the protection of the brain and sense organs. There are also, of course, the jawbones that support the teeth and gums and which enables us to bite and chew our food.
Most of the skull appears to consist of a single bone- a hard, unbroken dome. Actually, the brain cage or cranium consists of eight individual platelike bones which have fused together in the process of growth. At birth, these bones are separated, causing the soft spots of fontanelles we can readily feel on a baby's head. As the baby's brain enlarges, the bones grows along their edges to fill in the fontanelles, finally knitting together in what are called suture lines, somewhat resembling inexpertly mended clothes seams. Along the suture lines, the skull bones continue to grow until the individual's mature skull size is reached.
Most of the skull appears to consist of a single bone- a hard, unbroken dome. Actually, the brain cage or cranium consists of eight individual platelike bones which have fused together in the process of growth. At birth, these bones are separated, causing the soft spots of fontanelles we can readily feel on a baby's head. As the baby's brain enlarges, the bones grows along their edges to fill in the fontanelles, finally knitting together in what are called suture lines, somewhat resembling inexpertly mended clothes seams. Along the suture lines, the skull bones continue to grow until the individual's mature skull size is reached.
Within the framework of the axial skeleton lie all the most vital organs of the body. People have gone on living with loss of a hand or a leg- indeed, with loss of any or all of their limbs. But nobody can live without a brain, a heart, a liver, lungs, or kidneys- all of which are carried within the framework of axial skeleton. each part of the axial skeleton will be explained in the next post, which includes The Skull and The Backbone.
How the Bones of skeletal System Fit and Work Together
0 comments Posted by Delhi Fashion & Tailors at 10:24 PM
Medical textbooks name a total of 206 bones making up the skeletal system of a normal, adult human being. The word "normal" and "adult" are significant. A newborn baby normally has 33 vertebrae making up its backbones (also called spinal column or simply spine); but by the time a person reaches adulthood, the number of individual vertebrae has shrunk to 26.
The explanation: during the growth process, nine bottom vertebrae fuse naturally into just two. In like fashion, we "lose" some 60 bones as we grow up. Some otherwise perfectly normal adults have "extra" bones or "missing" bones. For example, although the normal number if ribs us 12 pairs, some adults may have 11; others may have 13 pairs.
Even a practicing physician might be hard-pressed to identify each of our 200-plus bones and describe its function. An easier way to gain a general understanding of various functions, capabilities- and weaknesses, too- of our bones is to visualize the skeletal system as a standing coatrack, say, about six feet high.
Call the central pole the backbone. About ten inches down from its top (the top of your skull) is a horizontal crossbar (your shoulders- collarbones and shoulder blades), approximately a foot-and-a-half across. Sixteen or so inches below the bottom of the top crossbar is another, shorter crossbar, broader and thicker- the pelvic girdle. The coatrack with its two crossbar is now a crude model of the bones of the head and trunk, collectively called axial skeleton. Its basics unit is the backbone, to which are attached the skull at the top, then the bones of the shoulder girdle, the ribs, and at the bottom, the bones of the pelvic girdle.
By hanging down (or appending) members from the two ends of the top crossbar, and doing the same at the lower crossbar, we would simulate what is called the appendicular skeleton- arms and hand, legs and feet.
Now, make the coatrack stand on its new legs, cut off the central pole just below the lower bar (if you wish, calling it man's lost tail), and you have the two main components of the skeletal system, joined together before you.
*Lets us look at each more closely in the next posts
The explanation: during the growth process, nine bottom vertebrae fuse naturally into just two. In like fashion, we "lose" some 60 bones as we grow up. Some otherwise perfectly normal adults have "extra" bones or "missing" bones. For example, although the normal number if ribs us 12 pairs, some adults may have 11; others may have 13 pairs.
Even a practicing physician might be hard-pressed to identify each of our 200-plus bones and describe its function. An easier way to gain a general understanding of various functions, capabilities- and weaknesses, too- of our bones is to visualize the skeletal system as a standing coatrack, say, about six feet high.
Call the central pole the backbone. About ten inches down from its top (the top of your skull) is a horizontal crossbar (your shoulders- collarbones and shoulder blades), approximately a foot-and-a-half across. Sixteen or so inches below the bottom of the top crossbar is another, shorter crossbar, broader and thicker- the pelvic girdle. The coatrack with its two crossbar is now a crude model of the bones of the head and trunk, collectively called axial skeleton. Its basics unit is the backbone, to which are attached the skull at the top, then the bones of the shoulder girdle, the ribs, and at the bottom, the bones of the pelvic girdle.
By hanging down (or appending) members from the two ends of the top crossbar, and doing the same at the lower crossbar, we would simulate what is called the appendicular skeleton- arms and hand, legs and feet.
Now, make the coatrack stand on its new legs, cut off the central pole just below the lower bar (if you wish, calling it man's lost tail), and you have the two main components of the skeletal system, joined together before you.
*Lets us look at each more closely in the next posts
Say "skeleton" to children and you probably conjure up in their minds a rickety structure of rigid sticks, or, to the more fanciful child, a clickety-clacketing collection of rattling bones cavorting under a Halloween moon. A look at almost any anatomical drawing of human skeletal system bears out the child's image: dry sticks of bones, stripped of skin and flesh, muscle and tendon- a grotesque caricature of a living human being.
Our living bones are something quite different. They are rigid, yes, but not entirely so: they also may bend a little and grow and repair themselves; and they are shaped and fitted so that- rather than the herky-jerky motions of wooden puppet- they permit the smooth grace and coordination power displayed by an accomplished athlete or a prima ballerina.
Our bones do not do just one thing but many things. Some bones, like the collarbone or clavic mainly give support to the other body structures. Others, like the skull and ribs, encase and protect vulnerable organs. Still others, like the metacarpus and phalanges that make up our hands and fingers, gives up mechanical advantages- leverage movement. There are even bones, the tiny ossicles in the middle ear, whose vibrations enables us to hear.
Finally, to think of bone simply as a structural member, like a solid steel girder in a skyscraper, ignores the fact that that the bone is living tissue. It is one of the busiest tissues in our bodies, a chemical factory that continually receiving, processing and shipping a wide variety of mineral salts, blood components, and a host of other vital materials.
Our living bones are something quite different. They are rigid, yes, but not entirely so: they also may bend a little and grow and repair themselves; and they are shaped and fitted so that- rather than the herky-jerky motions of wooden puppet- they permit the smooth grace and coordination power displayed by an accomplished athlete or a prima ballerina.
Our bones do not do just one thing but many things. Some bones, like the collarbone or clavic mainly give support to the other body structures. Others, like the skull and ribs, encase and protect vulnerable organs. Still others, like the metacarpus and phalanges that make up our hands and fingers, gives up mechanical advantages- leverage movement. There are even bones, the tiny ossicles in the middle ear, whose vibrations enables us to hear.
Finally, to think of bone simply as a structural member, like a solid steel girder in a skyscraper, ignores the fact that that the bone is living tissue. It is one of the busiest tissues in our bodies, a chemical factory that continually receiving, processing and shipping a wide variety of mineral salts, blood components, and a host of other vital materials.
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