The document discusses x-rays, including how they produce images by penetrating materials to varying degrees and exposing film, their discovery by Wilhelm Roentgen in 1895, and the purposes and risks of x-rays in medical imaging. It then identifies different bones and joints visible in sample x-ray images, such as the ribs, cranium, arm, leg, shoulder, wrist, and a dislocated shoulder.

1. Objectives:
You will be able to
…..explain how x rays produce images.
…..explain the dangers of and benefits
of getting x rays.
…..identify the types of joints in x rays.

2. What is an x ray?
An X-ray machine is basically like a camera.
It uses X-rays to expose the film, instead of
visible light.
X-rays are similar to light in that they are
electromagnetic waves, but they are more
energetic so they can penetrate many materials
to varying degrees. When the X-rays hit the film,
they expose it just as light would. Various
structures such as bone, fat, muscle, tumors
and all other masses absorb X-rays at
different levels (they do not let the x ray energy
pass through). The image on the film lets you
view distinct structures inside the body
because of the different levels of exposure on
the film.

3. How were x rays discovered?
In late 1895, a German physicist, W. C. Roentgen was
working with tubes similar to our fluorescent light bulbs. He
evacuated the tube of all air, filled it with a special gas, and
passed a high electric voltage through it. When he did this,
the tube would produce a fluorescent glow. Roentgen
shielded the tube with heavy black paper, and found that a
green colored fluorescent light could be seen coming from a
screen setting a few feet away from the tube. He realized
that he had produced a previously unknown "invisible light,"
or ray, that was being emitted from the tube; a ray that was
capable of passing through the heavy paper covering the
tube. Through additional experiments, he also found that
the new ray would pass through most substances casting
shadows of solid objects on pieces of film. He named the
new ray X-ray, because in mathematics "X" is used to
indicated the unknown quantity.
In his discovery Roentgen found that the X-ray would pass
through the tissue of humans leaving the bones and metals
visible. One of Roentgen’s first experiments late in 1895
was a film of his wife Bertha's hand with a ring on her
finger.

4. W. C. Roentgen

5. Why is a lead shield/apron placed
on you when you get an x ray?
X-rays emit radiation which cause
mutations to healthy cells. X-rays are
only harmful if you are exposed to
them for a really LONG time. X-rays you
get at the doctors are okay because
you don’t get them everyday. X rays are
more beneficial than they are harmful
because they can detect problems that
can be detrimental to your health.

7. Let’s see how many bones/joints
you can identify from the
following xrays…..

8. The ribs!
What kind of bone are these? FLAT
What kind of joint are the ribs? GLIDING
What’s this called? Sternum
?

9. What kind of bone is this? FLAT
What kind of joint is this? IMMOVEABLE
?
Cranium!

10. What kind of bones are these? LONG
What kind of joints are these? HINGE
Which one’s the arm?
Which one’s the leg?
How can you tell?
ARM LEG
Patella

11. What kind of joint is this?
FRACTURED HUMERUS
(What kind of fracture?)
What’s wrong here?
BALL & SOCKET
?
Shoulder!
Transverse

12. ?
What kind of joint is this? GLIDING
Wrist!
?
?
Radius
Ulna

13. Which x ray shows a problem?
What is the problem?
Dislocation!