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Anatomy&
Performance 
Physiology
Overview Module
Health Ventures, Inc. ©2014
CHAPTER 1: SKELETAL AND JOINT ANATOMY
The Anatomical Position
The anatomical position is an anatomical reference point or standard body
position that enables accurate description of body parts, body position,
directional terms, and movement terminology. That is the terminology used
refers back to the anatomic position regardless of the bodies actual position.
The anatomical position is standing upright; feet shoulder width apart, with
palms facing forward (anteriorly).
Directional Terms
Directional terms allow us to accurately describe the position of one part of the
body in relation to another. It can therefore assist in describing the movement
of a part of the body in relation to another. They include the following:
Superior When a body part is above another part or is closer to the head.
Inferior When a body part is below another body part or toward the feet.
Anterior/Ventral Towards the front of the body
Posterior/Dorsal The opposite of anterior/ventral; toward the back of the body.
Medial
Relates to an imaginary midline dividing the body in equal right and
left halves. Eg: The nose is medial to the eyes.
Lateral
Toward the side with respect to the imaginary midline. Eg: The
ears are lateral to the eyes
Proximal
When a body part that is closer to the trunk of the body than
another part. Eg: The elbow is proximal to the wrist.
Distal
The opposite of proximal. It means that a particular body part is
further from the trunk of the body than another part. Eg: The
fingers are distal to the wrist.
Superficial Situated near the surface.
Peripheral Also means outward or near the surface.
Deep Describes parts that are more internal.
3
BODY PLANES AND SECTIONS
These are terms that refer to sections of the body in terms of anatomical planes
(flat surfaces). These planes are imaginary lines - vertical or horizontal - drawn
through an upright body. The terms are used to
describe the movement, position, or location of a
specific body part.
Transverse Plane: The transverse plane is a plane
that divides the body into superior and inferior
portions; also called a horizontal, or cross-sectional,
plane.
Sagittal Plane: The sagittal plane is a vertical plane
through the longitudinal axis dividing the body into left
and right portions.
Coronal (Frontal) Plane: The frontal plane is a
vertical plane through the longitudinal axis, dividing
the body into dorsal (front) and ventral (back) portions.
Movement Terminology
Body planes
Source: Atlas of Skeletal Muscles
R J Stone & J A Stone, 1990
Whenever the body needs to move, bones, joints, muscles and tendons
combine to form a biomechanical lever system to achieve this. All movement
happens at joints and all movement of human body parts is described with
specific terminology. All these terms relate back to the basic anatomical
position.
Flexion
This is a bending movement that decreases the angle of
the joint. For example flexing the arm at the elbow joint,
decreasing the angle between the forearm and arm.
Extension
The exact opposite to flexion, increasing the angle of
the joint. For example extending the arm at the elbow
joint, increasing the angle between the forearm and
arm.
Rotation The turning of a bone around its long axis
Abduction
The movement of a limb away from the midline of the
body along the frontal plane. For example, moving the
arm from a position beside the body to a horizontal
position.
Adduction
The movement of a limb towards the midline of the body
along the frontal plane (opposite to abduction).
Circumduction
Consists of flexion, abduction, extension, and adduction
in one successive movement. The distal end of the limb
creates a circle in space whilst the pivot or joint remains
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stationary. For example, bowling a ball in cricket
requires circumduction.
Inversion and Eversion
Special movements of the foot performed by turning the
sole of the foot medially (inversion) and laterally
(eversion).
Pronation and
Supination
Refers to the movement of the radius around the ulna.
In the anatomical position (palms facing anteriorly) the
forearm is supinated. Pronation of the forearm occurs
when the palm moves to a posterior position. Supination
occurs when the palm moves back to the original
anatomical position.
Horizontal flexion
Movement of body part in the sagittal plane that
decreases the angle of the joint. For example, moving
the arm along the horizontal plane decreasing the angle
between the arm and chest.
Horizontal extension
Opposite to horizontal flexion, movement of limb in the
horizontal plane, increasing the angle of the joint.
Elevation and
Depression
Moving a body part superiorly (elevation) or moving the
elevated body part inferiorly (depression).
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The Skeleton
The adult human skeleton usually consists of 226 bones which are connected
by various joints. Muscles produce force which causes movement at these
joints.
These bones can be grouped in two divisions: axial skeleton and
appendicular skeleton.
The 80 bones of the axial skeleton form the vertical axis of the body. They
include the bones of the skull, vertebral column, ribs and breastbone or
sternum.
The appendicular skeleton consists of 126 bones and includes the free
appendages and their attachments to the axial skeleton. The free appendages
are the upper and lower extremities, or limbs, and their attachments that are
called girdles.
Functions of the skeletal system
The skeleton is what gives humans their shape. Two bones meet to form joints.
Bones provide skeletal muscles with attachment sites and therefore allow
movement to occur. The skeleton helps the body maintain form and posture.
The skeleton acts as protective armour for vital organs. Bones also store
minerals such as calcium and phosphorous. The production of blood cells is
occurs in the marrow cavities of some bones.
The functions of the skeleton at a glance:
Protection
Support
Movement
Mineral storage
Blood cell formations (haematopoiesis)
Bone Shapes
Bones come in various shapes.
Long bones: Long bones consist of a shaft and two ends. The shaft is
comprised mainly of compact bone while the ends are made up of spongy bone.
All bones of the limbs are long bones
Short bones: Short bones are cube-like bones that provide stability and
strength. The bones of the carpals and tarsals are short bones.
Flat bones: Flat bones are protective bones. They protect vital organs of the
body. The sternum and ribs are flat bones.
7
Skeleton: anterior view
Source: Atlas of Skeletal Muscles
R J Stone & J A Stone, 1990
8
Skeleton: posterior view
Source: Atlas of Skeletal Muscles
R J Stone & J A Stone, 1990
9
AXIAL SKELETON
Skull: The skull consists of facial bones and cranial bones (cranium). The
cranium is important, enclosing and protecting the delicate brain as well as
providing a site for attachment of head and neck muscles.
Vertebral column: The vertebral column (spine) serves as an axial support for
the trunk, protects the spinal cord, and provides attachment points for the ribs.
It consists of the sacrum, coccyx and 24 individual vertebrae that make up the
curves of the spine. These curves are then divided into three different divisions,
the cervical vertebrae, the thoracic vertebrae, and the lumbar vertebrae.
Cervical vertebrae: Consists of the seven vertebrae of the neck and
represents as a concave curvature (kyphotic curve). These vertebrae are
numbered from the top down (superior to inferior) and are identified as C1
C7.
Thoracic vertebrae: The thoracic vertebrae all articulate with the ribs. There
are 12 thoracic vertebrae and are numbered T1 T12 starting where the
cervical vertebrae left off. The thoracic vertebrae represents as a convex
(lordotic) curve in the middle of the back.
Lumbar vertebrae: Also referred to as the small of the back, the lumbar
vertebrae are the largest of the vertebrae in the human spine. They also provide
the bulk of the weight bearing function of the spine and as such account for the
majority of back injuries and complaints. It consists of 5 vertebrae numbered L1
– L5 and begins where the thoracic vertebrae left off
Sacrum: Formed by 5 fused vertebrae the sacrum articulates with L5 and with
the pelvis (hip) to form the sacroiliac joints of the body. It provides support for
the pelvic organs of the body.
Coccyx (Tail bone): Is a small triangular shaped bone formed by 4 fused
vertebrae and articulates with the sacrum. Other then providing a small amount
of support for the pelvic organs, the coccyx has very little purpose.
Ribs: There are 12 pairs of ribs which all articulate with the thoracic vertebrae.
The first seven ribs directly attach to the sternum and are referred to as true
ribs. The remaining ribs are called false ribs because they either indirectly
attach to the sternum or have no attachment at all. The ribs and sternum join to
make up the bony thorax, which forms a protective cavity around the bodies’
vital organs and the thoracic cavity (heart lungs and greater blood vessels).
Sternum: Also known as the breastbone, the sternum is the result of three
bones fused together, the manubrium, the body and the xiphoid process.
Manubrium: The superior portion of the sternum, the manubrium articulates
with the clavicles and the first two ribs.
10
Body: Forms the bulk of the sternum and articulates with the second to seventh
ribs.
Xiphoid Process: Forms the interior end of the sternum and serves as an
attachment point for the muscles of the abdomen.
APPENDICULAR SKELETON
The appendicular skeleton consists of the bones of the limbs and their girdles.
The appendicular skeleton provides mobility and as such, allows us to perform
everyday movements to interact with the external environment.
Upper Body
Clavicle: The clavicle is the most frequently broken bone in the body due to its’
relatively weakness and the compressive forces it can be subjected to. They
articulate with the sternum and the scapulae, acting as a brace, holding the
scapulae and arms out laterally
.
Scapulae: These are thin triangular flat bones that lie on the border of dorsal
surface of the rib cage between ribs 2 and 7. It articulates with the clavicle at
the acromioclavicular joint and the humerus at the glenohumeral joint
.
Humerus: A typical long bone, the humerus articulates with the scapulae of the
shoulder, and the radius and ulna of the forearm
.
Radius: The radius is one of two bones that form the skeleton of the forearm.
It articulates with the humerus, ulna and carpals of the wrist. In the anatomical
position, the radius is positioned lateral to the second bone of the forearm, the
ulna.
Ulna: Is slightly longer then the radius and is responsible for forming the elbow
joint with the humerus.
Carpals: The carpals are the small bones that make up the wrist; there are 8
in total. They articulate with each other, the metacarpals and the radius of the
forearm. There are five bones that radiate from the wrist to form the palm of the
hand.
Phalanges: Fingers or digits
LOWER BODY
Pelvis: The pelvis attaches the lower limbs to the axial skeleton. The pelvis is
secured to the axial skeleton via some of the strongest ligaments in the body.
The pelvis articulates with the femur and sacrum.
11 Fitness Trainer Education ©2015
Femur: The longest, strongest bone in the human body, the femur articulates
with the tibia, fibula and patella to also form the largest joint in the body, the
knee.
Patella: A triangular sesamoid bone enclosed in the quadriceps tendon that
secures the anterior thigh muscles to the tibia
.
Tibia: The tibia receives the weight of the body through the femur, transferring
it to the foot. It lies anterior to the fibula and articulates with the patella, femur,
fibula, and tarsals of the foot
.
Fibula: Posterior to the tibia, it articulates with the tibia, and tarsal bones in the
foot
.
Tarsals: There are seven tarsal bones that make up the posterior half of the
foot.
Metatarsals: These are the long bones of the foot. The heads of the
metatarsals make up the "ball" of the foot. The first metatarsal corresponds to
the big toe. The fifth metatarsal corresponds to the smallest toe.
Phalanges: There are fourteen small bones that make up the toes. There are
two phalanges in each large toe, and three in each smaller toe.
BONES AND JOINTS
Structure of a long bone
Most long bones have the same structure.
The shaft of a long bone is called the diaphysis and is made of thick compact
bone.
The ends of a long bone are called the epiphysis. The exterior of the epiphysis
is made of compact while the interior is comprised of spongy bone. Hyaline or
articular cartilage covers the epiphysis.
Bone remodeling
Our bones are not dormant but are continually changing. Bones can become
weaker or stronger. This change can be brought about by various reasons.
Alcohol consumption, smoking and fractures can result in a lower bone density.
Menopause which causes a decline in a females estrogen levels affects bone
strength. Low body fat levels can inhibit the absorption of some fat soluble
vitamins which can also weaken bones.
Bones, like the rest of our body require nutrients to stay healthy. Some of these
include – calcium, magnesium, protein, copper, vitamins A, C, D and K.
12 Fitness Trainer Education ©2015
Resistance training or any weight bearing exercise can help increase bone
strength.
Joints
The weakest parts of the skeleton, joints are the point at which two bone meet.
The range of movement at the joint is reliant on the structure, surrounding
ligaments, tendons and muscles. As a result, joints enable skeletal movement
whilst providing support against external forces place upon it (i.e. gravity
)
Joint types
Joints can be classified according to the degree and type of movement they
allow. The following types of joints can be recognized
:
Fibrous (or Immovable) Joints
These joints are firmly held together by a thin layer of strong connective tissue.
There is no movement between the bones such as the sutures of the skull
.
Sutures of the skull
Source: Human Anatomy & Physiology – 6
th
Edition
Elaine n. Marieb, RN PhD, 2004
Cartilaginous Joints: Cartilaginous joints are joints where the articular
surfaces of the bones forming the joints are attached to each other by means
of white fibrocartilaginous discs and ligaments that allow only a limited degree
of movement. Examples are the cartilaginous joint between the vertebrae, the
cartilage in the symphysis that binds the pubic bones together at the front of the
pelvic girdle and the cartilage in the joint between the sacrum and the hipbone.
Intervertebral joints
Source: Human Anatomy & Physiology – 6
th
Edition
Elaine n. Marieb, RN PhD, 2004
Synovial joints: Synovial joints make up the majority joints within the body.
They are joints in which the articulating bones are separated by a fluid filled
joint cavity. This allows synovial joints to be freely moveable and also allows
considerable freedom of movement. There are five characteristics associated
with a synovial joints, ligaments, articular cartilage, capsule, synovial
membrane, and synovial fluid and will be discussed here.
13 Fitness Trainer Education ©2015
Synovial joint
Source: Atlas of Skeletal Muscles
R J Stone & J A Stone, 1990
Ligaments: Provide support and stability for the otherwise fragile joint
.
Articular cartilage (Hyaline cartilage): Bone ends are covered with this
smooth surfaced cartilage, which provides a frictionless environment, whilst
providing a cushion support to help absorb compression placed on the joint
ends
.
Articular capsule: An envelope of tissue that surrounds a free moving joint
composed of an external layer of white fibrous tissue and an external synovial
membrane that secretes a lubricant into the joint
.
Synovial cavity (Joint cavity): Is a potential space that contains a small
amount of synovial fluid
14 Fitness Trainer Education ©2015
Synovial fluid: A lubricating fluid in the joint that reduces friction and helps
joints move more easily. Secreted by the synovial membrane, it is contained in
joint cavities, bursae, and tendon sheaths.
Synovial joints: Can be further classified into 6 major types depending upon
their structural features, and shape of articulating surfaces. These joints will be
described in more detail here:
Ball and socket: The sphere-shaped or crescent-shaped joint end articulates
with the cup-like socket of another. These joints have the greatest range of
motion providing multi-axial movement. The shoulder and hip joints are
examples of this type of joint.
Hinge: A cylindrically shaped joint end articulates with the half-pipe shaped end
of another. This association will only allow flexion and extension as for example
the articulation and movement of the elbow joint.
Plane: The articulating surfaces of these joints are essentially flat, and as such
they allow only small gliding or slipping movements. The articulation between
the vertebral articular processes is an example of this type of joint
.
Pivot: This is a joint where the cylindrical head of one bone surface fits into a
sleeve comprised bone or ligaments of another. An example of this type of joint
is the radioulnar joint where the head of the radius articulates and is secured
by a ligamentous ring secured to the ulna. This joint only provides movement
in one plane (uniaxial), in this case pronation and supination
.
Condyloid: The convex-shaped head of one bone surface articulates with the
concave-shaped surface of another. An example of this type of joint is the
articulation between the occipital bone of the skull and the atlas bone of the
cervical vertebrae. This joint articulation allows extension, flexion, abduction,
adduction, and circumduction of the head on the neck
.
Saddle: Similar to condyloid joints but provide a greater degree of freedom.
Both joints ends are shaped like a saddle, hence the name, and articulate to
allow flexion, extension, adduction, abduction, and circumduction. The joint of
the thumbs (carpometacarpal joints) are a clear example this type of joint.
15 Fitness Trainer Education ©2015
Types of synovial joints
Source: Atlas of Skeletal Muscles
R J Stone & J A Stone, 1990
16 Fitness Trainer Education ©2015
Major joints
Elbow : The elbow provides a stable and
smoothly operating hinge that allows flexion
and extension only. The elbow joint is formed
by three bones - the humerus of the upper
arm, and the bones of the forearm, the radius
laterally and the ulna medially. The joint is
actually formed by the trochlea of the
humerus articulating with the ulna and the
capitulum of the humerus articulating with the
head of the radius. Although there are two
sets of articulations, there is only one joint
capsule and a large bursa to lubricate the
joint. An extensive network of ligaments
The elbow joint
helps the elbow joint maintain its stability. The ligaments of
Source: Atlas of Skeletal Muscles
R J Stone & J A Stone, 1990
the elbow joint include the ulnar collateral, and the radial
collateral ligaments and the annular ligaments.
Inter-vertebral: The bodies of the adjoining vertebrae are joined by the
intervertebral discs whereas the facet joints (zygapophyseal joints), which are
synovial joints, link the articular processes. The major longitudinal ligaments
connecting the vertebrae are the
anterior and posterior ligaments
connecting the bodies of the vertebrae,
ligamentum flavum in between the
adjacent laminae and supraspinous
and interspinous ligaments connecting
the spines. These joints, ligaments, as
well as the muscles of the back,
stabilize the vertebral column.
Movements of the vertebral column are
forward flexion (40°), extension (15°),
lateral flexion (30°) and rotation (40°).
Rotation at the thoracic region is at
maximum whereas in the lumbar spine
it is very limited. Flexion and extension
on the other hand is limited in the
thoracic region due to the presence of
the rib cage.
Inter-vertebral joints
Source: Atlas of Skeletal Muscles
R J Stone & J A Stone, 1990
17 Fitness Trainer Education ©2015
Shoulder: The shoulder is made up of two separate joints - the glenohumeral
or shoulder joint which is formed
by the articulation of the rounded
head of the humerus or upper
arm bone into a cup-like
depression of the scapula called
the glenoid fossa. The
acromioclavicular joint is formed
by an articulation of the lateral
clavicle with the acromion
process of the scapula. Although
both of these joints are held
together by extensive ligament
and muscle attachments, certain
types of forces can weaken the
shoulder easily.
Shoulder joint
Source: Atlas of Skeletal Muscles
R J Stone & J A Stone, 1990
Pectoral girdle: Also called the shoulder girdle the pectoral girdle is composed
of four bones: the two clavicles and the two scapulae of the appendicular
skeleton. Usually, a "girdle" refers to something that encircles or is a complete
ring. However, the shoulder girdle is an incomplete ring, in the front, the sternum
separates the clavicles and at the back, there is a gap between the two
scapulae. The primary function of the pectoral girdle is to provide an attachment
point for the numerous muscles that allow the shoulder and elbow joints to
move. It also provides the connection between the upper extremities (the arms)
and the axial skeleton
.
Sacroiliac: There are 2 sacroiliac joints
formed by the articulation between the sacrum
and two ilium bones of the pelvis. Like the
other spinal structures, the sacroiliac joints
can be injured through acute trauma,
repetitive movements, and poor posture, to
name a few. The sacroiliac joint is another
spinal component that undergoes very large
spinal stresses. Either the ligaments
supporting the joints or the actual joint
surfaces can be a source of low back pain and
even refer pain into the lower extremities.
Sacroiliac joint
Source: Atlas of Skeletal Muscles
R J Stone & J A Stone, 1990
18 Fitness Trainer Education ©2015
Hip: The femoral head of the femur,
articulates with the acetabulum of the
pelvis to form the hip joint, thereby
creating a ball and socket joint. The
femoral head is normally held in the
socket by powerful ligaments that form a
complete sleeve around the joint. In the
course of your ordinary daily activities,
the weight placed on your hip is extremely
high--as much as three times your body
weight. Climbing stairs and rising from a
chair can raise that number even higher.
At the same time, force is being exerted
by the pull of the muscle on the femur,
while your pelvis rotates on the head of
the femur.
The knee joint
Source: Atlas of Skeletal Muscles
R J Stone & J A Stone, 1990
Knee: The knee
joint is a relatively
The hip joint
Source: Atlas of Skeletal Muscles
R J Stone & J A Stone, 1990
complex anatomical structure. In
addition to a variety of ligaments to
maintain stability and the presence of
large muscle groups, internally, it is a
classic example of a synovial joint. Both
the femur and tibia are enclosed in a joint
capsule lined with synovial tissue.
Between the condyles of the femur and
the condylar surface of the tibia are
menisci, which serve as shock absorbers
for the knee joint, located medially and
laterally inside the joint. Between each
muscle group are fluid-filled sacs called
bursa and the presence of fat bodies
named for their location that reduce
friction and lend added protection to the
joint capsule. During normal activity such
as walking or running, and even for
support while standing, the knee will
function superbly. It can tolerate
moderate stress without significant injury.
However, the knee lacks support to
withstand many types of injury, especially rotational forces such as those seen
in many athletic activities.
19 Fitness Trainer Education ©2015
Ankle: The ankle is a complex
mechanism. What we normally think of
as the ankle is actually made up of two
joints: the subtalar joint, and the true
ankle joint. The true ankle joint is
composed of 3 bones, seen above from
a front, or anterior, view: the tibia which
forms the inside, or medial, portion of
the ankle; the fibula which forms the
lateral or outside portion of the ankle;
and the talus underneath. The true
ankle joint is responsible for plantar
flexion and dorsi flexion of the foot.
Beneath the true ankle joint is the
second part of the ankle, the subtalar
joint, which consists of the talus on top
and calcaneus on the bottom. The
subtalar joint allows inversion and
eversion of the foot.
The ankle joint
Source: Atlas of Skeletal Muscles
R J Stone & J A Stone 1990
20 Fitness Trainer Education ©2015
SELF ASSESSMENT ACTIVITY
1. List the four main functions of the skeleton, providing a description of each.
2. Name the three types of bones and give an example of each.
3. Which two bones make up the forearm?
4. Which two bones make up the lower leg?
5. Name all the bones distal to the knee joint.
6. What is the opposite of inferior?
7. What bones are anterior to the spine?
8. Which is more lateral, the tibia or fibula?
9. What are the three structural components of bone?
10. What are the three categories of joints in the body?
11. Name at least six different structures that can be found within a synovial
joint.
12. List four synovial joints in the body.
21 Fitness Trainer Education ©2015