The skeletal system is made up of bones, joints, and connective tissues. It provides structure, support, and protection to the body. Bones come in two types - compact and spongy. They have structures like periosteum, Haversian canals, and contain cells like osteoblasts. Joints allow movement and include ligaments, tendons, cartilage, and fluid-filled sacs. Common diseases are osteoarthritis, osteoporosis, and bone tumors. Osteoarthritis causes joint pain and stiffness. Osteoporosis increases fracture risk. Bone tumors can be benign or cancerous and cause pain. Treatment depends on the condition and may include exercise, medication, or surgery.

1. The Skeletal System
II-Aristotle

2. Introduction
The human skeletal system is made up of
bones, the joints where bones meet, and the
connective tissues that hold the bones
together. The skeletal systerm is a living
framework for the body.

3. Bones
The human skeleton is made up
of 206 bones. A vertebrae
skeleton can be divided into
two parts: the axial and
appendicular skeletons. Each
bon of the skeleton is adapted
for its function by its size and
shape. For example, the long
bones of the arms and legs
support the large muscles that
attach to these bones. The
small, short bones of the wrists
allow flexibility. The flat bones of
the skull protect the brain.

4. Functions
The bones that make up the skeletal system
have several functions. Together, the bones
of the skeletal system support the body and
give it shape. In addition to support, bones
also serve the following functions:

5. Functions:
• Bones serve as anchors to which muscles
attach. Without the bones, muscles could not
move the body.
• Bones protect internal organs. For example, the
skull protects the brain, and the ribs protect the
heart, lungs and other organs.
• Bones make blood cells. Cells called stem cells
in the red bone marrow develop into red blood
cells and white blood cells.
• Bones store minerals, especially calcium and
phosphorus, that take part in many
biochemical reactions.

6. Bone Structure:
The outside of a bone, except at the ends
where the bones meet, is covered by a
membrane called the periosteum (payr-ee-
OS-tee-um). Branching through the
periosteum are small blood vessels. Blood
moving through these vessels carries nutrients
to the bone and takes away wastes.

7. Bone Structure:
Bone is referred to as either spongy or
compact. Spongy bone has many spaces. It
is found in the ends of long bones and in the
middle part of short, flat bones. Compact
bone is very dense and has few spaces. The
density of compact bone provides support in
long bones, such as in the shafts of the bones
in the upper arm (humerus) and the upper
leg (femur).

8. Bone Structure:
In the figure, find the large spaces in the spongy bone
that contain red bone marrow. Red bone marrow is a
material that produces blood cells. Another kind of bone
marrow, yellow bone marrow, is mostly made up of fat
cells. Yellow bone marrow is most often found in the
cavities within the shafts of long bones.

9. Bone Structure:
Notice the circular channels called Haversian
canals in the compact bone. These are spaces
through which nerves and blood vessels pass.
These canals also make compact bone lighter in
mass than they would be if they were solid.

10. Bone Structure:
Scattered throughout the bone are cells called
osteoblasts. Osteoblasts make the new bone cells
needed for the growth and repair of the bones. Found
in both compact and spongy bone, osteoblasts are
concentrated on the inner surface of the periosteum.

11. Joints
The places where bones meet are called joints.
Joints are classified as immovable, slightly
movable, or freely movable, depending on their
range of motion.
No movement takes place in immovable
joints, such as those between the bones of the
skull. Slightly movable joints, such as those
between the vertebrae, allow a small amount of
movement. Most motion takes place in freely
movable joints, such as the joints of the
shoulder, elbow, and knee.

12. Joints
Cushions of cartilage in joints
keep the ends of the bones
from rubbing against each
other. Some freely movable
joints are also protected by
fluid-filled sacs called bursae
(singular, bursa). In the figure,
find the bursa in the shoulder
joint. Bursae absorb the
impact of sudded pressure
on the joint. Some bursae are
present at birth, but others
can develop later in life in
heavily used joints.

13. Joints
The bones and muscles
of freely movable joints
are bound together by
bands of tough
connective tissues called
ligaments and tendons.
Ligaments are
connective tissues that
connect bones to other
bones. Tendons are
connective tissues that
attach muscles to bones.

14. Joints
There are several kinds of freely movable joints.
These joints are classified according to how they
move bones. One type is the ball-and socket joint,
which is formed by a bone with a ball-shaped end
that fits into a bone with a cup-shpaed end. Ball-
and-socket joints, such as the hip, allow a wide
range of movement.

15. Joints
Another joint type is the hinge. Hinge joints, such
as the knee and elbow, let bones move back and
forth like a door opening and closing. A gliding
joint, such as that found in the wrist, allows bones
to rotate around each other. To see how a pivot
joint operates, watch your elbow as you hold your
arm out in front of you and pretend to use a
screwdriver.

16. Diseases, Symptoms and Treatment
Osteoarthritis - is a group of mechanical
abnormalities involving degradation of
joints, including articular
cartilage and subchondral bone.

17. Diseases, Symptoms and Treatment
Symptoms may include joint
pain, tenderness, stiffness, locking, and
sometimes an effusion. A variety of causes—
hereditary, developmental, metabolic, and
mechanical—may initiate processes leading to
loss of cartilage. When bone surfaces become
less well protected by cartilage, bone may be
exposed and damaged. As a result of
decreased movement secondary to
pain, regional muscles may
atrophy, and ligaments may become more
lax.

18. Diseases, Symptoms and Treatment
Treatment generally involves a combination of
exercise, lifestyle modification, and analgesics.
If pain becomes debilitating, joint
replacement surgery may be used to improve
the quality of life.

19. Diseases, Symptoms and Treatment
Osteoporosis - is
a disease of bones that leads to an
increased risk of fracture. The disease
may be classified as primary type
1, primary type 2, or secondary. The
form of osteoporosis most common in
women after menopause is referred to
as primary type 1 or postmenopausal
osteoporosis. Primary type 2
osteoporosis or senile
osteoporosis occurs after age 75 and
is seen in both females and males at a
ratio of 2:1

20. Diseases, Symptoms and Treatment
Certain medications have been associated with
an increase in osteoporosis risk; only steroids
and anticonvulsants are classically associated,
but evidence is emerging with regard to other
drugs.

21. Diseases, Symptoms and Treatment
Bone Tumor - refers to a neoplastic growth of
tissue in bone. Abnormal growths found in the
bone can be either benign (noncancerous)
or malignant(cancerous).

22. Diseases, Symptoms and Treatment
The most common symptom of bone tumors
is pain, which will gradually increase over time.
A person may go weeks, months, and
sometimes years before they seek help; it
depends on the growth of the tumor. Many
patients will not experience any
symptoms, except for a painless mass. Some
bone tumors may weaken the structure of the
bone, causing pathologic fractures.

23. Diseases, Symptoms and Treatment
Treatment of bone tumors is highly dependent
on the type of tumor.
Chemotherapy and radiotherapy
Chemotherapy and radiotherapy are effective in some
tumors (such as Ewing's sarcoma) but less so in others
(such as chondrosarcoma). There are a variety of
chemotherapy treatment protocols for bone tumors.
The protocol with the best reported survival in children
and adults is an intra-arterial protocol where tumor
response is tracked by serial arteriogram. When tumor
response has reached >90% necrosis surgical
intervention is planned.

24. Diseases, Symptoms and Treatment
Medication
One of the major concerns is bone density and
bone loss. Non-
hormonal bisphosphonates increase bone
strength and are available as once-a-week
prescription pills. Metastron also known as
strontium-89 chloride is an intravenous
medication given to help with the pain and can
be given in three month intervals. Generic
Strontium Chloride Sr-89 Injection
UPS, manufactured by Bio-Nucleonics Inc., its
the generic version of Metastron.

25. Thank you for listening!