Functions of the skeletal system
Support
Hematopoesis (ie makes red blood cells, white blood cells, platelets in red bone marrow)
Protects your organs
Stores and excretes minerals
Assists in movement
Triglyceride or fat storage in yellow bone marrow
Types of bones
Long, short, flat, irregular
Long bone defined, examples
Greater length than width
Outer layer compact bone inner layer spongy bone at epyphisis
Examples:
Femur, tibia, humerus, radius
Structure of long bones
Epiphysis at ends, spongy (red bone marrow)
Diaphysis in the middle (yellow bone marrow)
Epiphyseal disc, the growth plate, cartilage–> bone
Medullary cavity, where marrows are (yellow)
Periosteum, covers bone
Articular cartialige, frictionless surface for joints
Metaphysis, where growth plate is located
Short bones defined, examples
Nearly equal in length than width, inner layer spongy, outer compact
No medullary cavity
Examples:
Carpals (wrist)
Tarsels (ankles)
Flat bones
Flat bone with inner layer of sponge compacted between outer compact
No medullary cavity
Examples:
Cranium
Sternum
Scapula
Irregular
Examples:
Vertebrae
Facial bones
Coxal bone (hip)
Sesamoid bones
Sutural bones
Prevent wear and tear on tendons
Ex: Patellar
Small bones between cranial structures
Osteogenic cells
Unspecialized bone cells/ stem cells
Produce osteoblasts
Osteoblasts
Build bone! (Deposition)
Osteocytes
Last stage of maturity final bone
Osteoclasts
Break down bone by releasing enzymes
What is osteoclastic activity called?
Resorption
What is another word for osteogenisis?
Ossification
When does bone ossification occur?
Formation of bones in embryo
Growth of bones in infancy to adulthood
Remodeling of bone throughout life
Repair of bone fractures
What are the two types of ossification?
Intramembranous and endochondral
Intramembranous- where does it occur and what happens
Occurs in flat bones of skull, replacing thin connective tissue with bone
Endochondral- where and what
Replacement of fetal cartialige skeletion with bone
In long, short, irregular bones
What is the soft spot in a newborns head?
Fontanel, where intramembranous ossification happens
Where does growth of bones occur?
Epiphyseal disc
Osteoblasts invite cartialige in disc –> Mature into osteocytes
What can cause irregular growth (ie gigantism/ dwarfism)
Hormones, too much = gigantism, too little = dwarfism
What can cause acromegaly?
Tumor on pituitary gland, releases growth hormone, makes you wider because you can’t grow anymore
What are the types of fractures?
Greenstick- partial bone break
Compound- bone is protruding out of skin
SImple- broken but not out of skin
How many bones in the axial skeleton?
80 bones
What bones are the axial skeleton?
Skull, hyoid, vertebral column, thoracic cage
Bones in your cranium (8)
Frontal bone, parietal bones, temporal bones, occipital bone, sphenoid, ethmoid
What are sinuses?
Hollow portion of bone, makes it weight less, modulate sound of voice
What bones have sinuses?
Frontal, sphenoid, ethmoid, maxillary
Parts of the temporal bone?
Zygomatic process, external auditory meatus (ear hole), mastoid process, styloid process,
Parts of occipital bone?
Foramen magnum (the hole on bottom, brain stem leading to spinal cord), occipital condyle
Sphenoid bone
Is irregular, butterfly/bat shape
Forms floor and sides
Connects cranium to facial bones
Does the sphenoid have sinuses?
Yes
Ethmoid bone
Is irregular, between the eye orbits, supports nasal cavity
What are the facial bones and how many are there?
2 nasal bones, 2 palatine bones, 2 lacrymal bones, 2 zygomatic bones, 2 maxilla bones, 2 inferior nasal conchae, 1 vomer bone and mandible
There are 14
What is the only movable bone in your face?
Mandible
What are the hyoid bones?
Malleus (2), incus (2), stapus (2)
What are the fontanels?
Anterior, posterior, anterolateral, posterolateral
What are the sections of the vertebral column in order?
Cervical, thoracic, lumbar, sacrum and cocyx
Cervical vertebrae
C1-C7
Thoracic vertabrae
T1-T12
Lumbar vertabrae
L1-L5
What is the atlas?
C1, allows you to nod yes
What is the aixs?
C2, allows you to rotate for no
Disorders of the vertebral column
Socoliosis (lateral curve), kyphosis (hunchback), lordosis (swayback, big booty back arched)
Parts of the thoracic cage?
Sternum, ribs, thoracic vertebrae
Parts of the sternum
Manubrium, body, xiphoid process
How many true ribs are there?
7 pairs, directly attached to sternum through costal cartialige
How many false ribs?
5 pairs are false, 2 pairs of those 5 are floating
What are the types of joints?
Movable, slightly movable, immovable
Types of freely movable joints
Hinge (allows movement on one axis, elbows, knees) ,
Pivot joint (rotation about only one axis, forearm)
Ball and socket (allows all movement, hip and shoulder)
Saddle (allows some rotation, cartometacarpal joint of thumb)
Gliding (wrists)
Condyloid (knuckles)
Flexion and extension
Bending and straightening
Inversion and eversion
Pointing in toward midline, pointing out
Looking like ballet
Plantar flexion and dorsiflexion
Flexing foot down, pointing foot up by heel
Supination and pronation
Palm facing up (spoon), palm facing down
Abduction and adduction
Away from body, toward body
Hyperextension
Going past 180 degrees
Circumduction
Blend of flexion, extension, abduction, adduction to create circular movement
How many bones are in the appendicular skeleton?
126
Pectoral girdle
Scapula (shoulder bone)
Clavicle (collarbone)
Upper limbs
Humerus (first arm bone), radius and ulna (below elbow, ulna on pinky side, radius on thumb side), carpals (wrist bones), metacarpals (palm bones), phalanges (fingers)
Pelvic girdle (coxal bones)
Made up of many bones together
Illium (the big part of pelvis), ischium (near pubis), pubis, acetabulum, symphysis pubis
Male vs female pelvic girdle
Women pelvis tends to be wider for child birthing
Functions of pelvic girdle?
Weight bearing, attachment for lower limbs, protection
Leg bones
Femur (thigh bone), patella (kneecap), tibia (big shin bone), fibula (little one), tarsals (ankle), metatarsals (kind of like palm), phalanges (toes)
Joint names
Tibiafemoral (knee), humeroulnar (elbow), Metacarpophalangeal (wrist), glenohumoral (shoulder), coxal (hip)
