Appendicular Skeleton
Introduction to the Appendicular Skeleton
• The axial skeleton was made
from bones that were in the
central part of the human body
• The appendicular skeleton
includes bones of the limbs and
supporting elements that
connect them to the trunk
• It has a great ability to change
the abilities and environment for
a human being
Introduction to the Appendicular Skeleton
• The axial skeleton was a system
that was designed to protect and
house vital organs
• Its primary uses were for keeping
important organs safe
• The appendicular skeleton is a
system that is designed to allow
movement and flexibility for an
organism
• It is generally the reason you can
experience the world around you
Introduction to the Appendicular Skeleton
• The appendicular is composed of
four different sections
• Each section is used to
manipulate the environment
around the individual
• Each section is composed of
entirely different bones that will
allow the individual the best
chance to survive
Introduction to the Appendicular Skeleton
• The pectoral girdle articulates
the upper limbs around the body
• The upper limbs are used to
manipulate tools and increase
balance
• The pelvic girdle handles weight
load and helps move the lower
limbs
• The lower limbs allow for
movement and support
The Pectoral Girdle
• Each arm articulates with the
trunk at the pectoral girdle
• It consists of two broad flat
scapulae and two clavicles
• The movements of the scapulae
and the clavicles position the
shoulder joints and provide
base for arm movement
The Pectoral Girdle
• The clavicles are “S” – shaped
bones that originate at the
superior lateral border of the
manubrium
• These bones are relatively fragile
and are the main reason that
people have to wear shoulder pads
when they play various contact
sports
• You can feel the clavicle move
against your sternum when you
raise or lower your shoulder joints
The Pectoral Girdle
• The anterior body of each
scapula forms a broad triangle
• The muscles that attach to the
scapula move the shoulder,
rotator cuff and the humorous
• This allows for a large range of
movements of the shoulder and
upper arm
Glenohumeral Joint
• Where the scapula and the
upper arm bones meet is called
the glenohumeral joint
• At the glenohumeral joint the
scapula articulates with the
humerus, the proximal bone of
the upper limb
• Both bones are set an anchored
in the joint with a mixture of
connective tissue and muscle
tissue
Glenohumeral Joint
• The bones of the shoulder stay
together with the help of the
rotator cuff
• The muscles and tendons of the
rotator cuff are designed to help
support ant help the shoulder stay
in place
• However, repeated motions
(especially overhead) can damage
the muscle and tendon that hold
the glenohumeral joint together
The Upper Limbs
• The upper limbs are designed for
the ability to use and utilize our
hands
• Unlike most organisms they are
not used to balance on the
ground
• They can be free to use during
any activity
The Upper Limbs
• The bones of the upper arm
consist of four separate sections
• The humerus (upper arm)
• The radius and ulna (lower arm)
• The carpals (wrist)
• The metacarpals and the
phalanges (hands)
Humerus
• The humerus is a long bone that
is found in the upper arm region
of the body
• This bone sits inside the
shoulder and articulates to
create all of the movements of
the upper arm
• It also interacts with the bones
of the lower arm to create a
twisting motion of the forearm
Humerus
• The most prominent feature of
this bone is the head, which is a
large projection on the proximal
end
• The large head will rotate when
the muscles of the rotator cuff
pull it in different directions
• The other end of the humerus
articulates at the condyle
• This section will rotate with the
radius and ulna
Radius and Ulna
• The radius and the ulna are parallel
bones that support the forearm
• It is often easy to get these two
confused
• However, the radius always lines up
with the thumb
• This is because when something is
“rad” you give it a thumbs up
• If that does not help, then the knob
you feel in your elbow is the ulna
Radius and Ulna
• The ulna has two major features
that allow the elbow to move
• The trochlear notch is where the
humerus sits and articulates
• The olecranon is the projection
that is posterior of the elbow
Radius and Ulna
• The radius is has two major
features that allows the radius to
move with the elbow
• The radial head articulates with
the end of the humerus
• The ulnar notch is near the wrist
and allows the forearm to twist
Radius and Ulna
• The radius and the ulna interact
very interestingly when
interacting with the humerus
• They will only bend one
direction when acting with the
humerus
• However they will rotate over
each other to allow the forearm
to twist at the wrist
Carpal Bones
• The wrist is a very interesting
section of the upper limb
• The wrist allows movement on two
different axis
• Side to side and forward back
• The twisting motion that is seen in
the lower arm is really dependent
on the radius and ulna
• It has eight bones that will all
articulate to allow a really wide
range of movement
Carpal Bones
• Out of the eight carpal bones,
four are considered distal (far)
and four are considered
proximal (near)
• The four proximal bones are
the…
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Scaphoid
Lunate
Triquetrum
Pisiform
Carpal Bones
• The remaining four bones are
considered distal (far)
• The distal bones are the…
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Trapezium
Trapezoid
Capitate
Hamate
Carpal Bones
• Breakage generally happens
when a person tries to stop their
own body weight
• The bones of the wrist and distal
ends of the radius and ulna are
all susceptible to damage when
someone breaks their wrist
• This generally should be fixed
quickly because small changes in
bone structure can cause large
amounts of pain
Metacarpals and Phalanges
• There are five different
metacarpal bones
• These bones articulate with the
carpals to move the palm of your
hand
• These bones make up the
majority of your palm
Metacarpals and Phalanges
• The metacarpals are give roman
numerals to define which one
them
• Metacarpal I is located just
below the thumb
• From there they increase in
number across the palm of the
hand
• Roman numeral I - Radius
Metacarpals and Phalanges
• Distal to the metacarpals is the
phalanges
• Each finger has three different
phalanges
• They are proximal, middle and
distal
• The thumb (pollex) has two
phalanges
• Proximal and distal
The Pelvic Girdle
• The pelvic girdle consists of two
very strong hip bones
• It often is included in a structure
called the pelvis that includes
the sacrum and the coccyx
• These bones are designed to
carry the weight of the body and
move the body
The Pelvic Girdle
• The pelvic bones consist of three
different parts
• The ilium is a the superior and
broad part to the hip bone.
• This provides attachment points for
muscles
• The ischium is posterior lower
section to the hip bone
• When seated, this part supports your
weight
• The pubis is the anterior lower
section to the hip bone
The Pelvis
• The pelvis consists of the hip
bones, the sacrum and the
coccyx
• They are held together by an
extensive collection of cartilage
• These bones are important for
providing support to everything
above them and making sure
your body can move while
upright
The Pelvis
• Males and females have many
differences in the pelvis
• These are due to the fact males
are generally heavier and
females bear children
• Some of the major differences
include…
• A broader pubic angle (greater
than 100 degrees)
• A wider more circular pelvic outlet
• An enlarged pelvic outlet
The Legs
• The legs contain the large bones
of the lower body
• These will be responsible for the
movement of the body
• They are also designed ot hold a
large amount of weight
• When standing on your feet a
large amount of weight is being
placed on a small surface of your
leg bones
The Legs
• The legs consist of four bones
• The femur is the bone of the
thigh
• The patella is more commonly
known as the kneecap
• The tibia and the fibula combine
to make the bones of the shin
The Femur
• The femur is the longest and
heaviest bone in the body
• It articulates at the hip and at
the knee
• It is often said that this bone is
the most painful thing in the
body to break
• Remember pain is subjective
http://youtu.be/L5W6JyF7br8?t=4m10s
The Femur
• The femur has a pronounced
head that articulates at the
pelvis
• Then the femoral shaft connects
the pelvis to the knee
• The patellar surface is the area
where the femur articulates at
the patella
Video
• Snapping your femur can come
from direct contact from a side
angle
• Mostly happens from older age
• https://www.youtube.com/watc
h?v=PEgkuoD5VsU
• https://www.youtube.com/watc
h?v=_LJCgGq946c
The Patella
• The patella is a bone located
within the patella tendon
• It is used to protect the delicate
inner workings of the knee
• Direct blows to the knee can be
diverted by the patella
The Patella
• The patella articulates at the
patellar surface in the femur
• This allows the patella to track up
and down in its own notch
• However if the patella tracks
sideways in the notch, there is
friction and rubbing
• This is commonly referred to as
runners knee
• This can be because of improper
shoes on hard or slanted surfaces
Tibia and Fibula
• The tibia and the fibula are the
bones of the lower leg
• These two bones articulate with
the knee and the ankle/foot
• The tibia is commonly known as
a shinbone
• Remember – Tibia = Toes
• The fibula posterior to the tibia
Tibia and Fibula
• The tibia is the major weight
bearing bone of the shin
• The fibula has such a small
diameter because it does not
help transfer weight to the ankle
or foot
• However, it is an important bone
to attach muscles to move the
ankle and foot
Tarsal Bones
• The tarsal bones make up the
ankle and the upper section of
the foot
• These sections are crucial to be
able to walk
• They transfer the weight from
the body to the ground and vice
versa
• These bones are significantly
thicker and stronger than their
counterparts in the wrist
Tarsal Bones
• There are 7 tarsal bones that
make up the foot and the ankle
• We will only be learning a few
• The talus transfers weight from
the legs to the rest of the foot
• Talus = Top = Tibia
• The calcaneus is commonly
referred to as the heel
• Most of the weight of the body is
transferred to the ground through
the heel
Metatarsals and Phalanges
• The metatarsals are the bones
of the middle foot
• These bones make up the foot
beginning in the middle of your
arch
• These bones articulate with the
metatarsals
Metatarsals and Phalanges
• The metatarsals are give a
roman numeral system similar to
the metacarpals
• The first metatarsal is the bone
associated with the big toe
• From there we label across II - V
Metatarsals and Phalanges
• The phalanges are the bones of
the toes
• Much like the fingers, there are
proximal middle and distal
sections to each toe
• However, the “great toe” (big
toe) is given the name hallux
• This toe only has two bones
Video
• https://www.youtube.com/watch?v=SLGfx4aKPE8