Download Unit 6 Skeletal system part 2

IV. Surface markings
A. Foramen – A rounded
passageway for blood vessels
nerves, ligaments (foramen
magnum, vertebral foramen,
obturator foramen)
B. Meatus – an tube-like
opening or passageway
( external auditory meatus)
C. Paranasal sinus – air-filled
chambers connected to the
nasal cavities (frontal sinus
D. Fossa – A shallow
depressionin or on a bone
(olecranon fossa)
E. Condyles – A large, smooth,
rounded articular prominence
(lateral and medial)
F. Head – The rounded articular
end of an epiphysis, separated
from the shaft by the neck
G. Facet – A small, smooth, flat
articular surface
H. Tuberosity – A roughened
process (deltoid tuberosity)
I. Trochanter – A large, blunt
projection only on femur
J. Crest – A prominent ridge or
border (iliac crest)
V. Skull – two sets of
bones – 8 cranial/14
facial
A. Sutures – seam or
stitch, immovable joint
found between skull
bones
1. Coronal – attaches the
frontal bone to the parietal
bones
2. Sagittal – extends from the
lambdoidal suture to the
coronal, separates the parietal
bones
3. Lambdoidal – separates the
occipital bone from parietal
4. Squamous – boundary
between parietal bone and
temporal bone
B. Cranial Bones – enclose the cranial cavity, fluidfilled to cushion and support the brain
1. Frontal bone – forms forehead, orbits, frontal sinuses
2. Parietal bones – two sides and roof of cranial cavity
3. Temporal bones – two interior lower sides and part of
cranial floor, mandibular fossa, forms
temporomandibular joint (TMJ)
-external auditory meastus – leads to inner ear
-mastoid process – attachment for muscles
-styloid process – attachment for muscles
4. Occipital – back of cranium for muscles and ligaments of tongue
and neck
-occipital condyles – articulate a joint with cervical vertebrae
-foramen magnum
5. Sphenoid bones – middle of base of the skull (bat with
outstretched wings)
-sphenoidal sinuses – drain into nasal cavity
- sella turcica – depression – contains pituitary gland
6. Ethmoid bone – light spongy bone located in the front part of the
floor of the cranium between the orbits
- contains superior and middle nasal conchae
C. Facial bones
1. Nasal bones – two, bridge of
nose
2. Maxillae – upper jaw
-contain alveoli into which
upper teeth are set
-cleft palate – improper fusion
of left and right sides
3. Zygomatic bones – two cheek
bones
4. Mandible – lower jaw
- mental foramen – hole in
mandible used as a dental
landmark
5. Lacrimal bones – smallest bones
in face
6. Palatine bones – posterior
portion of the hard palate
7. Inferior nasal conchae – two
scroll-like bones, inferior to
other nasal conchae –
filtration of air
8. Vomer – bone forms lower
and back part of nasal septum
D. Fontanelles – soft spots between cranial bones
of infants
E. Foramina – major openings
F. Hyoid Bone – suspended from the styloid process by
ligaments and muscles
- located between mandible and larynx
- supports tongue
- often fractured during strangulation
VI. Vertebral Column – composed of vertebrae,
encloses and protects spinal cord, supports head and
is a point of attachment for ribs and muscles of back
A.Divisions:
1. Intervertebral foramina
– openings between
vertebrae
2. Adult – 26 vertebrae
3. Made up of 7 cervical, 12
thoracic, 5 lumbar, 1
sacrum (5 fused), 1 coccyx
(4 fused)
4. 1st vertebra – atlas
5. Intervertebral disc –
fibrocartilage, elastic
structure
C. Curves
- four curves – 2 concave,
2 convex
- concave – thoracic,
sacral
- convex – cervical,
lumbar
- fetus – one concave
curve
- at three months,
cervical develops
- lumbar curve develops
with walking and
standing
C. Typical Vertebrae – vary in size, shape and detail
1. Body – disc-shaped front
portion – functions in
weight bearing
2. Arch – formed by pedicles
and lamina
3. Spinous process – sharp
projection, can see and
feel when spine is flexed
4. Vertebral foramen –
opening for the spinal
cord that forms the spinal
cord
5. Processes (7) – muscle
attachment and
articulations with
other vertebrae
D. Cervical Region – spinous process 2nd through 6th
- cervical vertebrae are bifid (cleft) – v-shaped
transverse foramen – blood vessels and nerves are
located here
C1 – atlas – no body or spinous process
C2 – axis – body has dens – projection
through the ring of the atlas to form a pivot
point for neck rotation
C7 – Vertebral prominens – large spinous
process
E. Thoracic Region
- larger and
stronger than
cervical vertebrae
- all except T11 and
T12 have facets for
rib articulation
F. Lumbar Region
- largest and strongest
- spinous process adapted for large back muscle
attachment
G. Sacrum and Coccyx
1. Sacrum – triangle- shaped, union of 5 bones,
fusion begins at age 16-18
- foundation of pelvic girdle
- sacral hiatus – anesthesia given here during
childbirth
2. Coccyx – Four bones, fuse with sacrum very late
VII. Thorax – entire chest region
- bony cage consisting of the
sternum, costal cartilage, ribs, and
the bodies of the thoracic
vertebrae
- encloses and protects the internal
organs
A.Sternum – breastbone, flat
bone, houses red marrow
1. Manubrium – upper portion,
articulates with the clavicles,
1st and 2nd ribs
2. Body – middle portion,
largest section, articulates with
ribs 2-8
3. Xiphoid process – lower
portion, point of reference for
CPR
B. Ribs – 12 pair
- increase in length from 1-7
- decrease in length from 8-12
- #s 1-7 attach to the sternum with
costal cartilage (hyaline) and are
called “true ribs”
- the last 5 pair are called “false ribs”
because they don’t attach to the
sternum
- #s 11-12 are called floating ribs
because they lack an anterior
articulation
- Intercostal spaces – between ribs,
are occupied by muscles, blood vessels,
nerves
1. Frontal bone
6. Zygomatic Bone
8. Maxilla
9. Mandible
13. Vomer
14. Inferior nasal concha
17. Nasal bones
18. Lacrimal bone
Identify #1, 6, 8, 9, 13, 14, 17, 18
Identify #1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 16, 19, 20, 23, 24, 25
1. Parietal bone
2. Coronal suture
3. Frontal bone
4. Nasal bone
5. Vomer
6. Lacrimal bone
7. Ethmoid bone
8. Zygomatic bone
9. Maxilla
10. Mandible
16. External auditory meatus
19. Temporal bone
20. Sphenoid bone
23. Squamosal suture
24. Lambdoidal suture
25. Occipital bone
1. Occipital bone
2. Lambdoidal suture
3. Parietal bone
4. Sagittal suture
5. Coronal suture
6. Frontal bone
Identify #1-4
1. Parietal bones
2. Sagittal suture
3. Lambdoidal suture
4. Occipital bone