Osteology

Anatomy

The term applied to the science of the structure of

the body

Physiology

he study of the function of the body organs

Osteology

The detailed study of the body of knowledge relating to the bones of the body

The adult human skeleton is composed of

206 primary bones

Bones provide the following:

1. Attachment for muscles

2. Mechanical basis for movement

3. Protection of internal organ

4. A frame to support the body

5. Storage for calcium, phosphorus, and other salts

6. Production of red and white blood cells

Correct Anatomic Position

Patient standing erect with the face and eyes directed forward, arms extended by the

sides with palms of the hands facing forward, heels together, and toes pointing

anteriorly

Four types of body planes

Sagittaal

Coronal

Horizontal

Oblique

The midsagittal plane and a horizontal plane intersect at the umbilicus and create the

boundaries.

This is useful for describing the location of the various abdominal organs.

Sthenic

• 50% of population

• Heart- moderately transverse

• Lungs- Moderate length

• Diaphragm- Moderately high

• Stomach- High, upper left

• Colon- spread evenly, slight dip in transverse

colon

• Gallbladder- Centered on right side, upper

abdomen

Hyposthenic

• 35% of population

• Organs and characteristics for this habitus are

intermediate between sthenic and asthenic

body habitus types; this habitus is the most

difficult to classify.

Asthenic

• 10% of population

• Heart- nearly vertical and at midline

• Lungs- long, apices above clavicles, may be

broader above base

• Diaphragm- Low

• Stomach- Low and medial, in the pelvis when

standing

• Colon- Low, folds on itself

• Gallbladder- Low and nearer the midline

Hypersthenic

• 5% of the population

• Heart- axis nearly transverse

• Lungs- Short, apices at or near clavicle

• Diaphragm- high

• Stomach- High, transverse, and in the middle

• Colon- Around periphery of abdomen

• Gallbladder- High, outside, lies more parallel

The 206 bones are divided into two main groups:

axial and appendicular

Axial Skeleton

Supports the skeleton and protects the head and trunk with 80 bones

Appendicular Skeleton

Allows the body to move in various positions and from place to place with its 126 bones

Compact bone

Strong, dense outer layer

Spongy bone

– Inner, less dense layer

– Contains a spiculated network called trabeculae

Trabeculae filled with

red and yellow marrow

Periosteum

tough fibrous connective tissue that covers bone, except at articular ends.

Compact bone

dense outer layer

Spongy/Cancellous bone

Less dense inner portion of bone

Trabeculae

Softer spongy bone contains a spiculated network of interconnecting spaces.

Medullary Cavity

contains trabeculae Filled with yellow marrow

Endosteum

The tissue lining the medullary cavity.

Bone Marrow

Red produces red and white blood cells found in ends of long bone. Yellow stores adipose fat cells.

Nutrient foramen

near the center of all long bones is an opening in the periosteum

Bone Development

• Ossification is the term that applies to the development and formation of bones

• Begins in the second month of embryonic life

• Two processes

– Intermembranous ossification

– Endochondral ossification

Intermembranous ossification

Flat bones- bone of skull, clavicles, mandible and sternum. Before birth these bones are not

joined.

Endochondral ossification

Short, irregular and long bones

Two distinct centers of development

Primary ossification- diaphysis and metaphysis

Secondary ossification- epiphysis

Classification of Bones

• Classified by shape

– Long

– Short

– Flat

– Irregular

– Sesamoid

Long Bones

Long bones found only in limbs

– Consist of body and two enlarged articular ends

– Consist of long cylindrical shaft called the body and

two enlarged, rounded ends that contain a smooth,

slippery articular surface.

– Examples: femur and humerus, the phalanges of the

fingers and toes are also considered long bones. A

primary function of long bones is to provide support.

Short bones

– Consist mainly of cancellous bone with a thin

outer layer of compact bone containing red

marrow.

– Example: carpal bones of

the wrist and tarsal bones of the

the ankle

Flat bones consist of two plates of compact

bones

– Middle layer of cancellous bone called diploë

– Examples: sternum, cranium and scapulae. The

flat surface provides protection, and their broad

surfaces allow muscle attachment.

Irregular bones are peculiarly shaped

– Examples: vertebrae, facial bones and pelvis. They

have compact bone on the exterior and cancellous

bone containing red marrow in the interior. They

serve for muscles, tendons and ligaments

attachment or they attach to other bones to

create joints.

Sesamoid bones

– Very small and oval

– Develop inside and beside tendons

– Protect the tendon from excessive wear

– Largest is patella

Three subdivisions based on mobility of joint

– Synarthroses = immovable

Sutures of the skull

– Amphiarthroses = slightly movable

Inferior tibiofibular joint

– Diarthroses = freely movable

Bones of most joints

Synarthroses

Synarthroses = immovable

Sutures of the skull

Amphiarthroses

slightly movable

Inferior tibiofibular joint

Diarthroses

freely movable Bones of most joints

Fibrous Joints

strongest joints in the body, virtually immovabel

Syndesmosis

an immovable joint or slightly

movable joint united by sheets of fibrous tissue.

Example- Inferior tibiofibular joint

Suture

An immovable joint occurring only in the

skull. Held together by strong connective tissue.

Example- sutures of the skull

Gomphosis

An immovable joint occurring only

in the roots of the teeth.

Cartilaginous Joints

similar to fibrous joints that

they do not have a joint cavity and they are virtually

immovable. Hyaline cartilage and fibrocartilage

unites these joints.

Symphysis

Slightly movable, example-pubic

symphysis or between each vertebral body

Synchondrosis

An immovable joint containing a

rigid cartilage that unites two bones.

Synovial Joints

permit a wide range of motion,

and they all are freely movable.

Gliding

uniaxial movement, example-

intercarpal and intertarsal joints of wrist and

foot

Hinge

uniaxial movement, permits only

flexion and extension. Example- elbow, knee

and ankle

Pivot

uniaxial movement, these joints allow

only rotation around a single axis. Example-

atlas and axis of cervical spine.

Ellipsoid

Biaxial movement, primary.

Movement in two directions at right angles to

each other. Examples- radiocarpal joint.

Saddle

Biaxial movement, this joint permits

movement in two axes. Example-

Carpometacarpal joint

Ball and Socket Join

multiaxial movement,

Example- hip joint and shoulder joint

Condyle

rounded process at an extremity.

Coracoid or Coronoid

crownlike process

Crest

ridgelike process

Epicondyle

projection above condyle

Facet

small, smooth-surfaced process for articulation with another structure.

Hamulus

hook-shaped process

Head

hornlike process on a bone

Horn

hornlike process on a bone

Line

less prominent ridge than a crest, a linear elevation.

Malleolus

club-shaped process

Protuberance

projecting part or prominence

Spine

sharp process

Styloid

long, pointed process

Trochanter

either of two large, rounded, and elevated processes.

Tubercle

small, rounded and elevated process.

Tuberosity

large, wounded and elevated process

Fissure

cleft or deep groove

Foramen

hole in a bone

Fossa

pit or hollow space

Groove

shallow linear channel

Meatus

ubelike passageway

Notch

an indentation into border of a bone

Sinus

recess, groove, cavity or hollow space

Sulcus

furrow or trench

Closed

fracture that does not break through

the skin

Open

Serious fracture in which broken bone

or bones project through the skin.

Nondisplaced

fracture in which bone retains

its normal alignment.

Displaced

serious fracture in which bones are

not in anatomic alignment.

Common classifications of fractures:

Compression

Open or compound

Simple

Greenstick

Transverse

Spiral or Oblique

Comminuted

Impacted

Radiation

is energy that is transmitted by waves through

space or through a medium (matter).

Ionization

is any process by which a neutral atom gains or

loses an electron, thus acquiring a net charge. This process

has the ability to disrupt the composition of matter.

Sound

Medical Sonography

Electrical

Electrocardiography

Heat (thermal)

Thermography

Magnetic

Magnetic resonance imaging

Electromagnetic

X-rays

Radio waves

Nuclear

Gamma radiation

Radiography

Uses electromagnetic energy

in the form of x-rays to create

medical images