AXIAL SKELETON Flashcards
This is composed of bones & cartilages forming the framework of the body; the bones, cartilages, joints & ligaments accounts for about 20% of body mass.
Skeletal and Articular System
This make up the bulk of the skeleton.
Bones
This is the nose, part of the ribs, and joints.
Cartilage
This connects bones and reinforce joints to allow movement while restricting motions in other directions.
Ligaments
How many bones are there in our body?
206 bones
The bones are divided into 2 divisions, what are these?
Axial and Appendicular
This forms the long axis of the body including the bones of the skull, vertebral column, rib cage & sternum.
Axial skeleton
These are the bones of the upper & lower limbs & girdles (shoulder & hip bones) that attach the limbs to the axial skeleton.
Appendicular skeleton
What are the functions of the bone?
Supports surrounding structures, protects vital visceral organs, gives attachment to the muscles & provides leverage in assisting body movements, produces blood cells, hematopoiesis; occurs in the bone marrow, storage of mineral salts, phosphorus & calcium
What are the three bone cells?
Osteoblast, osteoclast, and oscteocytes
BONES CELLS:
This cell is active in bone formation.
Osteoblast
BONE CELLS:
This cell is active in bone resorption.
Osteoclast
BONE CELL:
This is the principal cells of mature bone & surrounded by bone matrix.
Osteocytes
CLASSFICATION OF BONES ACCORDING TO SHAPE:
This consist of a shaft (diaphysis) & 2 extremities (epiphysis).
EX: humerus, radius, tibia, fibula
Long bones
CLASSFICATION OF BONES ACCORDING TO SHAPE:
These are the bones in the wrists & tarsal bones of the ankle.
Short bones
CLASSFICATION OF BONES ACCORDING TO SHAPE:
This consist of 2 flat plates of compact tissue enclosing a layer of spongy bone.
EX: ribs, scapula, parts of hip bone,
bones of the skull
Flat bones
CLASSFICATION OF BONES ACCORDING TO SHAPE:
These are the bones of peculiar & differing shapes.
EX: vertebrae & ossicles of the ear
Irregular bones
CLASSFICATION OF BONES ACCORDING TO SHAPE:
This is enclosed in a tendon & fascial tissue & found adjacent to joints.
EX: patella
Sesamoid bones
CLASSFICATION OF BONES ACCORDING TO DEVELOPMENT:
This involves the direct mineralization of dense connective tissue membrane forming bones.
EX: flat bones of the cranium
Bones formed by intramembranous ossification
CLASSFICATION OF BONES ACCORDING TO DEVELOPMENT:
This is the process where most bones in the body are formed; it involves replacement of hyaline cartilage by bone.
Bones formed by endochondral ossification
The axial skeleton has how many bones? and what are these?
80 bones; skull, hyoid bone, vertebrae, ribs, and sternum
How many bones are there in the skull, and what are these?
28 bones:
Cranial- 8
Facial- 14
Ear ossicles- 6
This enclose & protects the brain & furnish attachment sites for head & neck muscles; most of this bones are flat bone. All bones of the adult in this part are firmly united by interlocking joints and sutures EXCEPT the mandible.
Cranium
SUTURES OF THE SKULL:
This is where the parietal bones meet superiorly at the cranial midline.
Sagittal suture
SUTURES OF THE SKULL:
This is where the parietal bones meet the frontal bone anteriorly.
Coronal suture
SUTURES OF THE SKULL:
This is where the parietal bones meet the occipital bone posteriorly.
Lambdoid suture
SUTURES OF THE SKULL:
This is where the parietal and temporal bone meet on the lateral aspect of the skull.
Squamous suture
CRANIAL BONES:
This is the back and base of the skull.
Important features: foramen magnum, occipital condyles.
EX: occipital protuberance
Occipital
CRANIAL BONES:
This is the greater part of the superior lateral aspect of the skull.
Parietal
CRANIAL BONES:
This forms the forehead, most of the orbital roof and anterior cranial fossa.
Frontal
PART OF FRONTAL BONES:
This is the smooth portion between the orbits.
Glabella
PART OF FRONTAL BONES:
These areas are lateral to the glabella.
Frontal sinuses
CRANIAL BONES:
This forms the inferior lateral aspect of the skull & parts of cranial base; it contains the middle & inner ear structures; important feature is mastoid process
3 MAJOR PARTS: Squamous,
Tympanic, Petrous parts.
EX: Auditory meatus, Mastoid
process, and Styloid process.
Temporal bones
PART OF SPHENOID BONES:
This is the saddle-shaped depression in the sphenoid bone that contains the pituitary gland.
Sella turcica
CRANIAL BONES:
This is the bat-shaped bone that forms the midanterior base of the skull, forms the floor & lateral orbital floor. The important features are the 3 pairs of processes: Greater and lesser wing pterygoid processes, sphenoidal sinuses, and sella turica.
Sphenoid
CRANIAL BONES:
This is located between the nasal bones & sphenoid; it form part of the anterior cranial floor, medial walls of orbit, part of nasal septum, roof of nasal cavity; the important features are the cribriform plate, crista galli, perpendicular plate of ethmoid, middle conchae, and superior turbinates.
Ethmoid
PARTS OF ETHMOID BONE:
This forms the roof of the nasal cavity & floor of the anterior cranial fossa.
Cribriform plate
PARTS OF ETHMOID BONE:
This helps secure the brain in the cranial cavity.
Crista galli
PARTS OF ETHMOID BONE:
This forms the superior part of the nasal septum.
Perpendicular plate of ethmoid
PARTS OF ETHMOID BONE:
This forms a protective shield over the sinuses.
Middle conchae
PARTS OF ETHMOID BONE:
This protect the olfactory bulb.
Superior turbinates
This form the framework of the face; contain cavities for special sense organs; provide opening for air & food passages; secure the teeth; anchor the facial muscles of expression
Facial bones
How many bones are there in facial bones? And what are these?
14 bones:
Nasal- 2
Lacrimal- 2
Inferior nasal concha- 2
Maxilla- 2
Palatine- 2
Zygomatic-2
Mandible- 1
Vomer- 1
FACIAL BONES:
This is the thin & rectangular bones; it lies between the maxillary bones; it is fused medially and bridge of the nose to bind together the cartilage that forms individual nose contours and shapes.
Nasal bone
FACIAL BONES:
This is fused medially to upper jaw; it is considered the keystone bones of the facial skeleton where all the facial bones articulate except the mandible.
Maxillary or maxillae bones
FACIAL BONES:
This is also known as the cheek bones.
* Articulates with:
POSTERIOR- zygomatic process of
the temporal bone
SUPERIOR- zygomatic process of the
frontal bone
ANTERIOR- zygomatic process of the
maxillae
Zygomatic (malar) bone
FACIAL BONES:
This is U-shaped; the largest & strongest bone of the face; it consists of body, 2 rami, and coronoid & condylar processes.
Mandibular (lower jaw)
FACIAL BONES:
This is fingernail shaped; it forms the anterior medial wall of orbit.
Lacrimal bones
FACIAL BONES:
This is located between the maxillae and the pterygoid process of the sphenoid bone; it is formed from 2 bony plates: horizontal &
perpendicular plates; it also form the posterior nasal cavity & part of hard palate.
Palatine bones
FACIAL BONES:
This is slender & plow-shaped bone; it forms the posterior part of the nasal septum
Vomer
This is thin, curved bones in the nasal cavity; it project medially from the lateral wall of nasal cavity; it filters and humidify the air that we breathe.
Inferior nasal conchae
There are 6 in number of this bone; this is the small bones in the middle ear in the temporal bone.
Auditory ossicles
What are the bones in the auditory ossicles?
Malleus (hammer), Incus (anvil), and Stapes (stirrups)
These are the cone-shaped bony cavities; it encases the eyes & lacrimal glands; it is formed by 7 bones: Frontal, sphenoid, zygomatic, maxillae, palatine, lacrimal & ethmoid bones
Orbits
This is the passage of optic nerve
Optic foramen
This is mucosa-lined, air-filled sinuses inside the frontal, sphenoid, ethmoid & paired maxillary bones; it functions as warm & humidify the air, lightens the skull, and enhance resonance of the voice
Paranasal sinuses
This is a horseshoe shaped in upper part of anterior
neck; the only bone that does not directly articulate with any bone of the body but anchored by a ligament; it acts as movable base for the tongue
Parts: body & 2 cornua (horns)
Hyoid bone
This is composed of 51 bones: the vertebrae, ribs, and sternum
Trunk
This is also called the spine or spinal column; it is the framework of the back; s-shaped; it functions as an axial support of the trunk, transmits weight of the trunk to LE, protects the spinal cord, serves as an attachment for the ribs & muscles of the back & neck
Vertebrae
What are the bones in the vertebrae?
Cervical- 7
Thoracic- 12
Lumbar- 5
Sacrum- 1 (5 fused)
Coccyx – 1 (4 fused)
This is the vertebrae in the neck region
Cervical vertebrae
Cervical and thoracic curvatures
Concave posteriorly
Lumbar and sacral curvatures
Convex posteriorly
The passage of vertebral artery (important feature of cervical vertebrae) is?
Transverse foramen
What are the types of cervical vertebrae?
Typical: C3-C6 (has bifid spine)
Atypical: C1 (ATLAS), C2 (AXIS), C7 (VERTEBRAE PROMINENS)
CERVICAL VERTEBRAE:
This has no body and spinous process.
C1 (ATLAS)
CERVICAL VERTEBRAE:
It has odontoid process.
C2 (AXIS)
CERVICAL VERTEBRAE:
This acts as a pivot for rotation of the atlas.
Dens
CERVICAL VERTEBRAE:
It has long single spine, and is not bifid.
C7 (VERTEBRA PROMINENS)
It has small facets for the ribs (demifacets); the vertebral foramen is circular; spinous process long & points sharply downward; transverse process with facets except T11 & T12; it increases in size from 1st to last; it is body heart shaped
Thoracic vertebrae
This is commonly referred to as the small of the
back; it receives the most stress; have sturdier structure because of its weight bearing function; the articular processes lock the vertebrae together to prevent rotation; flexion, extension & lateral flexion possible
Lumbar vertebra
What are the unique characteristics of lumbar vertebrae?
Body- massive & kidney shaped
Pedicles & laminae are shorter & thicker Spinous processes are short, flat, hatchet shaped
Vertebral foramen triangular
This is triangular in shape; formed by 5 bones; shapes the posterior wall of the pelvis
Sacrum
This is formed because the laminae of the 5th & sometimes the 4th failed to fuse medially
Sacral hiatus
This is also known as the tail bone; small triangular bone; formed by fusion of 4 or 5 bones
Coccyx
This forms a protective cage for the vital organs of the thoracic cavity; serves as an attachment of muscles; consists of rib, sternum & costal cartilages, and thoracic vertebrae.
Thoracic cage
This is the spaces between the ribs; occupied by intercostal muscles; lift & depress the thorax during
breathing
Intercostal spaces
This is flat, narrow bone located in the midanterior chest; it resembles a dagger
Sternum
What are the 3 parts of sternum?
MANUBRIUM- upper part
BODY- middle part
XIPHOID PROCESS- pointy end
3 ANATOMICAL LANDMARKS OF STERNUM:
This is where the left common carotid artery
issues from the aorta
Jugular (suprasternal) notch
3 ANATOMICAL LANDMARKS OF STERNUM:
This is for PE & listening for sounds of heart
valves
Sternal angle
3 ANATOMICAL LANDMARKS OF STERNUM:
This is at level with heart lying on the diaphragm
Xiphesternal joint
RIBS:
1-7 ribs: attached to the ribs by their
own costal cartilages
True ribs (vertebrosternal)
RIBS:
8-10th ribs: attached to the sternum
by the 7th costal cartilage
FALSE RIBS (VERTEBROCHONDRAL)
RIBS:
11-12th ribs: no anterior attachment
RIBS (VERTEBRAL)
