Skeletal System: Axial Division Flashcards
How many UNFUSED vertebral column?
24
How many FUSED vertebral column?
9
5 Regions of Vertebrae
CERVICAL THORACIC LUMBAR SACRUM COCCYGEAL
CERVICAL REGION
Atlas, Axis, C3 - C7
most unstable bc of high degree of flexibility
THORACIC REGION
T1 - T12
12 bones separated by intervertebral discs
has costal facets on vertebral body, transverse process w transverse costal facets
larger than cervical bones, smaller than lumbar bones
has smaller foramens
superior and interior articular facets are almost vertical
LUMBAR REGION
L1 - L5
largest vertebrae that carries most weight
large vertebral body, large non bifid spinous process
flexion, extension and some rotation
SACRUM REGION
S1 - S5
triangular bone between lateral pelvis bones
has median sacral crest which surrounds 4 spinous tubercles
has SACRAL CANAL above and SACRAL HIATUS inferior which contains spinal nerve ending cauda equina
COCCYX
3-5 fused terminal bones
aka tailbone. provides attachment for muscles of lower limb
PRIMARY CURVATURE
aka ACCOMODATORY
convex (outward) curvature aka KYPHOSIS
thoracic and sacral region
SECONDARY CURVATURE
aka COMPENSATORY
concave curvatures aka LORDOSIS
found in cervical and lumbar regions
When does Primary and Secondary Curvature appear?
- Primary curvature occurs during fetal development
2. Secondary curvature occurs several months after birth during the shift from crawling to sitting to walking
Atypical Cervical Vertebraes
Atlas, Axis, C7
ATLAS
aka C1
atypical bs missing spinous process and vertebral body
AXIS
aka C2
atypical bc of ODONTOID PEG/PROCESS aka DENS - bony superior projection that fits between transverse ligament and Atlas’ lateral mass
Typical Thoracic Vertebrae
T5-T8
long, vertically oriented spinal processes
allos rotary movement but limits flexion, extension, and lateral mvmt
Atypical Thoracic Vertebrae
T1-T4, T9-T12
T1-4
spinous process is almost horizontal
T1 is most prominent and has complete facet on lateral surface and superior of vertebral body
T9-T12
looks similar to lumbar vertebra bs they have tubercles
INTERVERTEBRAL DISC
separates each cervival, thoracic, and lumbar vertebrae
INTERVERTEBRAL FORAMEN
opening formed bw the vertebral bodies and articular processes of 2 adjacent spinal vertebrae
acts as a passageway be spinal canal and periphery for spinal nerves to exit
there are 2 intervertebral foramens - left and right
2 Layers of Intervertebral Discs
ANNULUS FIBROSUS - tough outer layer
NUCLEUS PULPOSUS - softer inner layer
ANNULUS FIBROSUS
outer layer of disc composed of multiple layers of fibrous collagen
composition limits the rotation of the vertebrae
NUCLEUS PULPOSUS
inner layer of disc that is a jelly-like substance
spreads compressive forces evenly over vertebral body surface
prevents friction be two vertebrae as they move
ALA of sacrum
2 superior wings of sacrum
responsible for transmitting weight from upper body to sacroiliac joints
THORACIC CAGE 3 GROUPS
1 Ribcage and Costal Cartilages
2 Thoracic Vertebrae and their Intervertebral (IV) discs
3 Sternum
Superior Boundary of Thoracic Cage
superior thoracic aperture is formed by superior border of manubrium anteriorly,
superior surface of first rib laterally,
and body of T1 posteriorly
Inferior Boundary of Thoracic Cage
T12 posteriorly, T11-T12 posterolaterally, 7-10 Costal Cartilage anterolaterally, Xiphoid Process anteriorly
Lateral Boundary of Thoracic Cage
12 Costal Cartilages and 12 ribs on each side
Anterior Boundary of Thoracic Cage
sternum on midline and 12 Costal Cartilages
Posterior Boundary of Thoracic Cage
thoracic vertebrae at midline and associated ribs
Functions of Thoracic Wall
- protect heart, lungs, neurovascular structures, and superiority located abdominal organs
- provide attachment sites for respiratory muscles
- attachment sites for muscles that belong to other regions of body (i.e. neck, upper limb, abdomen)
MANUBRIUM
widest and thickest, superior part of Sternum
has slight u shape superiorly aka JUGULAR NOTCH
on superiolaterally are CLAVICULAR NOTCH
laterally on each side are Costal Notch I and COSTA NOTCH II
ANGLE OF LOUIS is inferior sternal angle
BODY OF STERNUM
longest part of sternum w transverse ridges on anterior surface
Costal Notches II-VII
Costal Notch VII articulates costal cartilages 7-10
XIPHOID PROCESS
most inferior part of Sternum
Articulates w superior Body of Sternum at xiphisternal joint
RIBS
consist of head, neck tubercle, and shaft
Ribs w 1 Articular facet on their head
1, 10-12
Ribs that lack neck and tubercle
11 12
Ribs w extra bony features
1 2
HEAD of Ribs
round posterior extremity
contains 1-2 Articular Surface for corresponding superior articular surface of Thoracic Vertebrae
NECK of Ribs
narrower section that connects HEAD to SHAFT of rib
TUBERCLE of ribs
lies posteriorly at junction of neck and shaft of rib
SHAFT of ribs
longest part to provide attachment sites for respiratory muscles
has COSTAL GROOVE in inferior aspect of internal surface
has ANTERIOR SURFACE for costal cartilages to attach to
COSTAL GROOVE
provides space for intercostal artery, nerve, and vein to run
3 Types of Ribs
1 TRUE RIBS
2 FALSE RIBS
3 FLOATING RIBS
TRUE RIBS
Ribs who’s Costal Cartilages are directly attached to Sternum
Ribs 1-7
FALSE RIBS
Ribs indiretly attached to sternum
Ribs 8-10 are attached to Costal Cartilage of Rib 7
FLOATING RIBS
ribs whos costal cartilage do not have attachment to the sternum
Ribs 11 - 12
Movement of Thoracic Cage
1 Inspiration - contraction os muscles causes ribs to move superiority, sternum to move anteriorly, and diaphragm to move inferiorly
2 Expiration - muscles relax and ribs move inferiority, diaphragm returns upwards
Movements of Ribcage
when inferior aspect of sternum moves anterior, it increases the diameter of thoracic cage
when ribcage moves superior, it increases the lateral diameter of thoracic cage
Bones of Pectoral/Shoulder Girdle
connects upper limbs to trunk
consist of Scapula and Clavicle
ACROMION
spine of scapula that projects laterally
CLAVICLE
S shaped bone that connects to sternum and scapula
RADIUS
Lateral and shorter bone of the forearm
PROXIMAL - HEAD (articulates w radial notch of Ulna, NECK, and RADIAL TUBEROSITY
BODY
DISTAL - broader than proximal end. has STYLOID PROCESS projection laterally, ULNAR NOTCH
Common forearm fractures
1 Colles Fracture - distal displacement from falling on outstretched hands
2 Smith’s Fracture - distal displacement of hand/wrist from falling onto back of hands
ULNA
most medial and longer forearm. Ulna is the stabilizer
composed of proximal end, shaft, and distal end
proximal part of Ula
massive hook which consist of OLCRANEON PROCESS (pointy elbow) and CORANOID PROCESS (projects fr anterior of ulna)
on lateral side is RADIAL NOTCH (concave)
most distal side is ULNAR TUBEROSITY (where brachailis muscle attaches)
distal end of ULNA
smooth rounded head
has ULNAR STYLOID PROCESS (cylindrical projection on the posterior head of Ulna)
DOES NOT participate w wrist joints!!!
WRIST
made of 8 carpal bones
allows for large degree of flexibility
2 ROWS
PROXIMAL ROW
from lateral to medial of wrists
SCAPHOID (most commonly fractured when person falls on their hand)
LUNATE
TRIQUETRUM
PISIFORM (anterior of triquetrum)
DISTAL ROW
from lateral to medial
TRAPEZIUM
TRAPEZOID
CAPITATE
HAMATE (has a process called HOOK OF HAMATE)
METACARPALS
I - THUMB II - INDEX III - MIDDLE IV - RING V - LITTLE FINGER
distal ends form the knuckles
14 PHALANGES
5 PROXIMAL
4 MIDDLE
5 DISTAL
*thumb doesnt have a middle phalanx
BONY PELVIS
basin-like bony structure composed of left/right hip bones, sacrum, and coccyx.
orientation is slightly tilted anteriorly which means the weight of internal organs are supported by the pubic bone
HIP BONE
composed of 3 fused irregular bones: ILIUM (superiorly), ISCHIUM (posteroinferiorly), and PUBIS (anteroinferiorly)
Weight bearing, protection, attachment site for trunk and limb muscles, and skeletal framework for birth canal
BONY PELVIS JOINTS
fibrous joint called PUBIC SYMPHYSIS connects right/left hip bones
LEFT/RIGHT SACROILIAC JOINTS articulates the lateral aspect of sacrum to right/left iliac bones.
SACROILIAC JOINT
articulates the sacrum to the right and left ilium of the hip
responsible for the eight transfer from axial skeleton down to lower limbs
PELVIC INLET
superior aperture of pelvis
defines the boundary bw abdominal and pelvic cavities
composed of PUBIC SYMPHYSIS, ARCUATE LINE of the ILIUM, sacral part of pelvic brinm, and SACRAL PROMONTORY
heart shaped in males; oval shaped in females
PELVIC OUTLET
Coccyx,SACROTUBEROUS LIGAMENT, ISCHIAL TEBEROSITY, ISCHIOPUBIC RAMUS, and PUBIC SYMPHYSIS
diamond shaped on both sexes but larger in females
FALSE PELVIS
superior portion of pelvis; superior of pelvic inlet
cup-shape area of iliac crest and oliac fossae
TRUE PELVIS
superior to pelvic outlet and inferior to pelvic inlet
PELVIC CAVITY
space contained within TRUE PELVIS and surrounded by fibromuscular structures of pelvic wall, and pelvic floor
organs: urinary bladder, rectum, pelvic parts of genitelia,
SCIATIC FORAMENS
different fr other openings in body bc its not completely enclosed by bones
GREATER SCIATIC FORAMEN enclosed by sciatic notch, sacrospinous ligament, and sacrum
LESSER SCIATIC FORAMEN enclosed by sciatic notch, sacrospinous ligament and sacrotuberous ligament
ACETABULUM
area of hip bone that articulates with HEAD OF FEMUR and made of ilium, ischium, and pubis bone.
alsmost hemispherical cavity anteroinferiorly
OBTURATOR FORAMEN
opening between ischium, pubis bone, and acetabulum
SKULL
22 bones
subdivided into NEUROCRANIUM (skullcap and cranial base) and VISCEROCRANIUM (face)
NEUROCRANIUM
4 unpaired bones in midline:
FRONTAL, ETHMOID, SPHENOID, OCCIPITAL
4 bilateral pairs:
(2)TEMPORAL BONES, (2) PARIETAL BONES
VISCEROCRANIUM
3 unpaired bones
MANDIBLE, VOMER
6 paired
NASAL BONE, MAXILLAE, ZYGOMATIC, NASAL CONCHAE, LACRIMAL, PALATINE
CRANIAL FOSSAE
step like depression within cranial cavity which allows for cerebellum, brainstem, to rest against skull
3 main:
ANTERIOR, MIDDLE, POSTERIOR
SUTURES
fibrous joints connected via dense connective tissue
strong, stable, inmovable
during early dvlpt. known as FONTANELLES and then they ossify
4 Cranial Sutures
CORONAL
SAGITTAL
LABDOID
SQUAMOUS
CORONAL SUTURE
connects frontal bone (anteriorly) and 2 parietal bones (posteriorly)
SAGITTAL SUTURE
runs anterior to posterior connecting 2 parietal bones
SQUAMOUS SUTURE
only bilateral suture
connects temporal bone (inferiorly) to parietal bone (superiorly)
LAMBDOID SUTURE
connects occipital bone (posterior and inferiorly) to 2 parietal bones (superiorly)
PARANASAL SINUSES
series of cavities along the nose or nasal cavity
lined w mucus producing cells
main functions: decrease overall weight of skull, and add resonance to the voice
FRONTAL SINUS
superior and medial to the orbits of eyes
MAXILLARY SINUSES
2 largest sinuses
inferior to frontal sinuses
drains superiorly and most prime to infection
SPHENOIDAL SINUSES
posterior to sphenoid bones (almost completely center of skull) is sphneoidal sinuses
ETHMOIDAL SINUS
aka ETHMOID AIR CELLS
can be broken down to as many as 18 cells in an adult
FORAMINA OF THE SKULLS
opening thru which cranial nerves, arteries, veins, and other structures pass though to enter/exit the brain
identified by following cranial nerves:
CN-I starts anteriorly and ends with CN-XII posteriorly
LIST OF FORAMINAS OF SKULL
CRIBRIFORM PLATE OPTIC FORAMEN/CANAL SUPERIOR ORBITAL FISSURE FORAMEN ROTUNDUM FORAMEN OVALE FORAMEN SPINOSUM STYLOMASTOID FORAMEN INTERNAL ACOUSTIC MEATUS JUGULAR FORAMEN HYPOGLOSSAL NERVE FORAMEN MAGNUM FORAMEN LACERUM
CRIBRIFORM PLATE
CN-I
most anterior aspect of skull located w/in ethmoid bone
OPTIC FORAMEN/CANAL
CN-II and ophthalmic artery
posterior to cribriform plate; first of many openings of sphenoid bone
SUPERIOR ORBITAL FISSURE
opens into orbit for CN-III (ocuomotor), IV (trochlear), V1 (ophthalmic div. of trigeminal nerve),
larger than avg opening; boomerang shaped
FORAMEN ROTUNDUM
CN V2 (maxillary div. of trigeminal nerve) CN V3 (mandibular division of trigeminal nerve)
FORAMEN SPINOSUM
no CN; middle meningeal artery/vein pass thrusmallest opening of all sphenoid bones; posterolateral of foramen ovale
INTERNAL ACOUSTIC MEATUS
CN-VII (facial nerve), CN-VIII (vestibulocochlear) temporal bone (petrous ridge)
JUGULAR FORAMEN
CN-IX(glossopharyngeal nerve), CN-X(vagus nerve), CN-XI (spinal accessory nerve)
FORAMEN MAGNUM
largest openng in skull for SPINAL CORD
no CN
FORAMEN LACERUM
Internal Carotid Artery appears at superior point (doesn’t pass thru, just bounces off) bw sphenoid and temporal bone
covered in cartilage
HYPOGLOSSAL CANAL
CN-XII hypoglossal nerve
inferior surface of skull
MANDIBLE
has ALVEOLAR PROCESS that holes mandibular teeth
2 U shaped processes in most superior:
CONDYLE OF THE MANDIBLE (most posterior) and CORONOID PROCESS OF MANDIBLE (anterior to condyle)
CONDYLE OF MANDIBLE
important for temporo-mandibular joing
CORONOID PROCESS OF MANDIBLE
important for attachment of muscles for movement
RAMUS OF THE MANDIBLE
inferior to Condyle and Coronoid of Mandible, posterolateral to Body of Mandible
has sharp 90 degree angle called ANGLE OF THE MANDIBLE
Body of Mandible
most anterior portion
RAMUS OF THE MANDIBLE
inferior to Condyle and Coronoid of Mandible, posterolateral to Body of Mandible
has sharp 90 degree angle called ANGLE OF THE MANDIBLE
in medial surface, has MANDIBULAR FORAMEN (for nerves, blood vessels, for sensation on chill, lower lip, buccal gingivae, and teeth)
Body of Mandible
most anterior portion
has ALVEOLAR PROCESS (for teeth) and 2 MENTAL FORAMEN (small passageway for MENTAL NERVE)
TEMPOROMANDIBULAR JOINT
(TMJ)
hinge type of synovial joint (allows mvmt in more planes than avg hinge joint)
2 bony features separated by fibrocartilage disc: MANDIBULAR PROCESS (of mandible) and MANDIBULAR FOSSA (of temporal bone)
3 TEMPOROMANDIBULAR JOINT MVMT
elevation
depression
protraction
retraction
2 sets of Teeth
1 PRIMARY (DECIDUOUS, 20 teeth) 2 SECONDARY (PERMANENT, 32 teeth)
4 Quadrants of Teeth
L + R Maxilla
L + R Mandible
3 Components of Tooth
Crown
Neck covered by GINGIVAL (gum)
Root embedded in alveolar bone
GOMPHOSIS JOINT
fibrous joint that attached tooth to bone
Categories of Teeth
INCISORS (8 total; 2 in each medial quadrant)
CANINE (4 total, 1 lateral to incisors in each quadrant)
PREMOLARS (8 total, 2 lateral to canine in each quadrant)
MOLARS (12 total, 3 in each quad, most posterior)