By Rich Mursheno
Audience: Anyone wanting to learn about the skeletal
system
Anatomy- the study of
structure
Physiology- the study
of function
Skeletal System
*Total of 206 bones
*Serves as attachment
points for organs and
softer body tissues
*Protect vital organs
*movement is carried out
by the interaction of the
skeletal and muscular
systems
*Supports the body
*Houses bone marrow
tissue (used for blood
cell formation)
What
organs
????
Divisions of Skeletal System
Axial Skeleton
Consists of 80 bones
Includes skull, rib cage, vertebral column
Supports and protects organs
Provides framework for muscles that:
(1)adjust positions of neck, head, and
trunk (2)perform respiratory
movements (3) anchor and stabilize
the appendicular bones
Divisions of Skeletal System
Appendicular Skeleton
*Consists of 126 bones
*Makes up the
appendages and
girdles that attach
appendages to the
body
*pectoral girdle consists
of the clavicle and
scapula.
*pelvic girdle is formed by
the two coxal bones
which are fused
anteriorly
Long Bones
*Includes a bone that is longer than it is wide
*growth plates (epiphysis) at either end
*a hard outer surface of compact bone
*a spongy inner known an cancellous bone
containing bone marrow
*ends of the bone covered in hyaline cartilage to
help protect the bone and aid shock absorption
Humerus
Tibia
Femur
Short Bones
*approximately as wide as they are long
*primary function of providing support and stability
with little movement
*consist of only a thin layer of compact, hard bone
with cancellous bone on the inside along with
relatively large amounts of bone marrow
Carpals
Tarsals
Flat Bones
*strong, flat plates of bone
*Function is protection of the bodies vital organs and
being a base for muscular attachment
*Anterior and posterior surfaces are formed of
compact bone to provide strength for protection
with the center consisting of cancellous (spongy)
bone and varying amounts of bone marrow
*In adults, the highest number of red blood cells are
formed in flat bones
Ribs and
Sternum
Scapula
Cranium
Irregular Bones
*bones which do not fall into any other category, due
to their non-uniform shape
*primarily consist of cancellous bone, with a thin outer
layer of compact bone
*Protect nervous tissue and serve as an anchor for
skeletal muscle attachments
Examples of Irregular Bones
Mandible
Sacrum
Vertebrae
Types of Bones
Sesamoid Bones
*usually short or irregular bones
*usually present in a tendon where it passes over a
joint which serves to protect the tendon
*modify pressure, to diminish friction, and occasionally
to alter the direction of a muscle pull.
Examples of Sesamoid Bones
Patella
Pisiform
What Are Bones Made Of?
*The outer layer of a bone is compact bone, which is
hard and dense
*The next layer is spongy bone, which is like
honeycomb, lighter and slightly flexible
*The inner layer of some bones, but not all is bone
marrow, which is jelly like
*Bone marrow is used for blood cell formation
Types of Fractures
transverse
oblique
greenstick
*Transverse: This type of fracture occurs when the
bone breaks clean across. The break is straight
across and through, leaving the bone in two
pieces.
*Oblique: The oblique fracture occurs when the
fracture is a result of a diagonal break completely
across the bone.
*Greenstick: The greenstick fracture occurs when a
broken bone isn’t quite separated.
Types of Fractures
*Compression: A compression fracture happens when the
bone is crushed and flattened.
*Hairline: A thin crack or break in the bone is a hairline
fracture, generally associated with stress fractures.
*Spiral: A spiral fracture happens when the break twists
around the bone. These are more common in injuries
where the bone was twisted under pressure.
*Impacted: impacted fractures are identified when the
fragments of bone are driven into each other.
Types Of Fractures
Impacted
Compression
Hairline
Spiral
General Bone Health
*It is important to eat the right foods to keep
healthy bones
*Foods that contain calcium such as dairy
products can help bone growth and strength
*Throughout your life time it is important to
exercise
*Even with age you must exercise: it can reduce
probability for fractures and chances of getting
diseases such as osteoporosis