Topic 10 -Skeletal system Flashcards
anatomical position
feet, face and palms facing forward
axial skeleton 4parts
number of bones
skull hyoid bone vertebral column thoracic cage -sternum plus ribs 80 bones
appendicular skeleton 4 parts
limbs and bones that attach them to the axial skeleton (girdles)
126 bones
pectoral girdle
pelvic girdle
upper limb (arm, forearm and hands)
lower limb (thigh, leg and foot)
connections between bones equals
articulations (joints)
ex humerus articulates with the scapula
Skull 3 main bone groupings
cranium 8 bones (next to brain)
facial bones 14 bones
auditory ossicles 6 bones (3 bones on each side in middle of ears)
cranium 8 bones
1 frontal (forehead) 2 parietal 2 temporal 1 sphenoid 1 ethmoid -forms superior and middle conchae 1 occipital
facial bones 14
2 nasal 2maxillae 2 zygomatic 2 lacrimal 2 palatine 2 inferior nasal conchae 1 vomer 1mandible
hard palate
2 palatine and 2 maxillae
auditory ossicles
malleus
incus
stapes
hyoid bone
no articulations (joints/connections to other bones) attaches muscles of tongue and neck to assist in swallowing
vertebral column
26 vertebrae, 5 regions 7 cervical 12 thoracic 5 lumbar 1 sacrum 1 coccyx
typical vertebral structure (8)
1) body- thick anterior portion
2) spinous process median posterior projection
3) transverse process -lateral bony projections for muscle attachment
4) laminae -connects the processes
5) pedicles -connects the body to the transverse process
6) vertebral foramen -opening for spinal cord
7) superior and inferior articular process (with facets=articular surfaces), articulate with vertebrae above and below
8) intervertebral foramina -exit for spinal nerves
c1, c2
atypical
c3-c7
typical
c1
atlas
no body, no spinous process
articulates with occipital condyles of skull
allows nodding “yes” motion
c2
axis
dens (odontoid process)
pivot joint around which the atlas swivels
allows shaking “no” motion
what do c1 -c7 all have
transverse foramina, opening for blood supply
Thoracic T1-T12 all articulate with
ribs via costal facets
lumbar L1-L5 support……
all large …….
support head
all large bodies and rectangular spinous processes
sacrum
5 fused vertebrae
articulates with ilium (appendicular skeleton) and 5th lumbar vertebrae
coccyx
3-5 fused vertebrae usually 4
tailbone
curvature of the spinal column
cervical + lumbar
curved convex anteriorly = concave posteriorly
curvature of spinal column
thoracic + sacral
curved concave anteriorly = convex posteriorly
3 types of abnormal curvature
scoliosis
kyphosis
lordosis
scoliosis
spinal column curves laterally
kyphosis
exaggerated thoracic curve (hunchback)
lordosis
exaggerated lumbar curve (swayback)
thoracic cage is made up of
sternum and ribs
sternum 3 parts
manubrium- superior
body -middle
xiphoid process -inferior
ribs 12 pairs
articulate posteriorly with T1 to T12
7 pairs of true ribs, direct attachment to sternum via costal cartilage (hyaline cartilage)
5 pairs of false ribs, attach indirectly to sternum via costal cartilage 8-10 or not at all= floating ribs 11,12 embedded in muscle
Pectoral girdle (upper limb girdle) is made up of
clavicle
scapula
clavicle (collarbone)
articulates with sternum (manibrium) and scapula (acromion process)
connects axial and appendicular skeletons
scapula (4 parts)
spine (on posterior)
acromion process -articulates with clavicle
glenoid fossa/cavity -articulates with head of humerus
coracoid process -attaches muscle for arm and chest
pelvic girdle (lower limb girdle) is made up of
composed of 2 os coxae (hip bones) each with 3 bones
ilium -articulates with sacrum
ischium -most inferior part = the ischial tuberosity
pubis -left and right joined by pubic symphysis
joints of pelvic girdle
pubic symphysis
sacroiliac -sacrum and ilium
acetabulum -articulates with head of femur -all 3 bones of os coxa join here
upper limb in anatomical position
humerus radius (lateral) ulna (medial) carpals (8) wrist metacarpals (5) palms phalanges (14) fingers
all long bones except carpals
lower limb in anatomical position
femur
patella (knee cap)
Fibula (lateral)
tibia (medial)
tarsals (7) -talus -articulates with tibia
-calcaneus = heel bone
metatarsals (5) =sole
phalanges (14) = digits (toe)
all long bones except patella and tarsals
components of long bone (8)
Diaphysis Epiphysis Epiphyseal plate Epiphyseal line Medullary cavity Periosteum Endosteum Articular cavity
diaphysis (long bone)
shaft (body)
Epiphysis (long bone)
proximal and distal extremities
Epiphyseal plate (long bone)
hyaline cartilage
used for bone growth (length)
Epiphyseal line (long bone)
replaces plate with bone when growth is completed
plate/line -where diaphysis and epiphysis meet
Medullary cavity (long bone)
red marrow in child, yellow marrow in adults
periosteum (long bone)
external surface 2 layers of CT -outer = dense irregular -inner = mainly osteoblasts and osteoclasts allows bone to grow in diameter
Endosteum (long bone)
lines medullary cavity and canals (contains osteoblasts and osteoclasts)
articular cartilage (long bone)
hyaline (only at articulation process)
prevents friction between bones (no periosteum here)
Bone in general consists of
cells
matrix
cells of bone
osteoblasts, mature into osteocytes
osteocytes, mature bone cells
osteoclasts, reabsorb old cells
matrix of bone
ground of substance
-hydroxyapatite =insoluble calcium phosphate salts (strength)
collagen fires (flexibility) water
2 types of bone
compact bones
spongy bones
compact bone
Where is it located?
Composed of …
covers external surface of all bone
composed of osteon
each osteon contains (5)
lamellae -bone matrix, arranged in concentric circles
lacunae (with osteocytes)
space within matrix where osteocytes live
between lamellae
canaliculi
small canals that connect osteocytes with blood supply and to other osteocytes
central canal
contains blood vessels and nerves
is lined with endosteum
perforating canals
perpendicular to central canal
carry blood supply from periosteum to central canals and medullary cavity
spongy bone
no osteons
have trabeculae (made of irregularly arranged lamellae)
canaliculi connect osteocytes in lacunae
spongy bone is found in
flat and irregular bones (skull, ribs, vertebrae) long bones -epiphyses -lining medullary cavity -spaces contain bone marrow red marrow produces blood cells
cartilage (CT)
hyaline cartilage chondrocytes in lacunae matrix: shiny ground substance contains chondroitin sulphate + hyaluronic acid collagen fibres and water non vascular
Articulation and joints
what are the classes?
point of contact between two or more bones
2 classes, structural and functional
structural classification
based on presence or absence of joint cavity
type of connecting tissue
types of structural joints
fibrous
cartilaginous
synovial joints
Fibrous joints
no joint cavity
fibrous CT connects bones
ex sutures in skull (fontanels in new born)
Cartilaginous joints
no joint cavity
cartilage attaches bones
ex pubic symphysis and costal cartilage of ribs
synovial joints
ex shoulder, elbow, hip, knee
structure: articular cartilage (hyaline) joint cavity -contains synovial fluid -articular joint capsule outerlayer = fibrous capsule attaches to periosteum, may have ligaments within (capsule= thickened) or separate inner layer = synovial membrane (CT only) secretes synovial fluid
types of synovial joints according to shape of articulating bone (4)
plane/gliding
hinge
pivot
ball and socket
plane/gliding joints
flat surfaces
ex sacroiliac
hinge joints
concave/convex surfaces
ex elbow and knee
pivot joints
projection in a ring
ex dens on axis in atlas
ball and socket joints
great freedom of movement
ex humerus in glenoid fossa
ex femer in acetabulum (hip)
functional classification based on degree of movement 3 types
synarthrotic
amphiarthrotic
diarthrotic
synarthrotic joints
immovable
ex skull sutures
amphiarthrotic joints
slightly movable
ex pubic symphysis
diarthrotic joints
freely movable synovial joints
ex hip and shoulder
