Anatomy: Skeletal System

Osteology

Study of bones

appendicular skeleton

upper and lower extremities
Ex. Pectural + Pelvic Girdles

axial skeleton

Medium axis of body
Ex. Skull, middle ear, hyoid, vertebrae, ribcage

sutural bones

Form when sutures don't totally connect with the rest of the skull

long bones

Longer than wide
Serve as levers,
great amount of movement

Short Bones

nearly equal length and width
limited motion, gliding movement
-allow movement in multiple directions
Ex. Carpals + Tarsals

Flat bones

enclose and protect soft organs + provide broad surfacing for muscle attachment
Ex. Cranium, ribs, pelvis, scapulae,

irregular bones

very elaborate
Ex. Some skull bones, vertebrae

Epiphysis

End of a long bone

Diaphysis

shaft of a long bone

articular cartilage

covers the surfaces of bones where they come together to form joints
lubricant

Periosteum

Covers the outside of the diaphysis

compact bone

Hard, dense bone tissue that is beneath the outer membrane of a bone

spongy bone

Layer of bone tissue having many small spaces and found just inside the layer of compact bone.

medullary cavity

hollow cavity within bone in which bone marrow produces blood cells

Osteoblasts

cells that harden and form bone

Osteoclasts

cells that break down inner portion of bones form the medullary cavity

Epiphyseal disk

Cartilaginous layer within the long bone epiphysis that grows

Hematopoiesis

blood cell formation

Hyoid

supports the tongue

Sacrum

bone formed from five vertebrae fused together near the base of the spinal column

Coccyx

four vertebrae fused together to form the tailbone

xiphoid process

Small projection at the end of the sternum

external auditory meatus

ear canal

Mastoid process

round projection on the temporal bone behind the ear

fontanels

Soft spots on a baby's skull, for head compaction to fit easier through birth canal

intervertebral discs

Pads of cartilage that separate vertebrae

Atlas

supports the head; C1

Axis

Lies within the Atlas, which supports the head; C2

cervical vertebrae

C1-C7; first set of seven bones, forming the neck
great movement

thoracic vertebrae

the second set of 12 vertebrae; form the outward curve of the spine and are known as T1 through T12;

lumbar vertebrae

L1-L5 lower back; Greatest weight bearing

pelvic sacral foramina

passageways for nerves and blood vessels

True Ribs

first 7 pairs of ribs; attach directly to sternum

False Ribs

last 5 pairs of ribs; attach by cartilage to sternum

floating ribs

last two pairs of ribs; do not attach to sternum; broken most frequently

Clavicle

collar bone; helps hold shoulder in place

spine of scapula

shoulder blade

glenoid cavity

Space in which the head of the humerus sits

Acetabulum

Depression in which the head of the humerus sits

radial tuberosity

where biceps tendon attaches

Patella

kneecap; not attached to any other bone

Calcaneous

heel

Talus

Supports Tibia and Fibula

Joint

Junction between bones

Fibrous Joints

Lie between bones that closely contact one another

Cartilaginous Joints

Disks of cartilage that connect bones
they allow for equal weight distribution
Ex. vertebrae + symphysis pubis

Synovial Joints

allow considerable movement (elbow and knee)
enclosed in joint capsule

Meniscus

pad

bursae

sacs

ball + socket joint

widest range of movement in all direction as well as rotation

Condyloid Joint

Oval end of one bone that fits into a cavity of another
great movement but no rotation
Ex. Between metacarpals + phalanges

Hinge Joint

convex surface of one bone fits into the concave surface of another
only 2 directional movement
Ex. elbow, knee, phalanges

Gliding Joints

Slightly curved bones glide past one another
-wrist, ankle, SI

Pivot Joint

allows for rotational movement
Ex. Radius/Ulna + Neck

Saddle Joint

Shaped like a saddle; allow for great movement
Ex. Thumb

Flexion

bending a part so that joint angle decreases
-Ex. Bending knee

Extension

Bending part so that joint angle increases

Dorsiflexion

Bending foot so toes point towards the shin.

What is "Your Mom" in Spanish?

Tu Madre

Plantar Flexion

bending foot at ankle so that toes point down

Hyperextension

extension beyond anatomical position

Abduction

Movement away from the midline of the body
Ex. Lifting arms sideways

Adduction

Movement toward the midline of the body
Ex. Returning arm to side of body

Rotation

moving a part around an axis
Ex. Twisting head side to side

Circumduction

moving a part so that its end follows a circular path
Ex. moving finger in circular motion

Pronation

turning of the hand so the palm faces downward

Supination

turning of the hand so the palm faces upward
Ex. As Mr. Aisenbrey says,"Bringing a cup of soup to your face."

Eversion

Turning foot so the sole faces outward

Inversion

Turning the foot so the sole faces inward

Retraction

moving a part backward
Ex. Pulling the jaw backwards

Protraction

Moving a part forward
Ex. Thrusting Chin Forward

Elevation

Raising a part
Ex. Shrugging shoulders

Depression

A prolonged feeling of helplessness, hopelessness, and sadness
OR.......
Lowering a part; Ex. Drooping your shoulders