Chapter 7: Skeleton Flashcards
What is the body’s most complex bony structure?
the skull
How does the frontal bone articulate with the parietal bones?
the frontal bone articulates posteriorly with the parietal bones via the coronal suture
What do the parietal bones form?
The most superior and lateral aspects of the skull (the tops and the sides)
What are the 4 sutures associated with the parietal bones?
Coronal suture
Sagittal suture
Lamboid suture
Squamosal suture
Coronal suture
articulation between parietal bones and frontal bone anteriorly
Sagittal suture is where
right and left parietal bones meet superiorly
Lamboid suture is where
parietal bones meet the occipital bone posteriorly
Squamosal suture is where
parietal and temporal bones meet
What does the occipital bone form?
It forms most of the skull’s posterior wall and base.
Occipitomastoid suture is where
the occipital and temporal bones meet
What do the temporal bones form?
They form the inferolateral aspects of the skull and parts of the cranial floor
How many regions are the temporal bones divided in to?
4 major regions squamous tympanic mastoid petrous
Describe the shape of the sphenoid bone
it is the butterfly-shaped bone that spans the width of the middle cranial fossa
What is unique about the sphenoid bone and its articulations?
It forms the central wedge that articulates with all other cranial bones
What is unique about the ethmoid bone?
it is the most deep of the skull bones and lies between the sphenoid and nasal bones
Describe wormian bones
They are tiny irregular shaped bones that appear within sutures
How many bones make up the facial bones?
14
Which 2 facial bones are unpaired?
the mandible and vomer are unpaired
Describe how the maxillary bones are fused and what they make up.
The maxillary bones are medially fused bones that make up the upper jaw and the central portion of the facial skeleton
the maxillary bones articulate with
all other facial bones except the mandible
What is another name for the zygomatic bones?
Cheekbones
Be able to label bones of the skull
everything that was discussed in lecture is fair game
What are the seven bones that form the orbits?
Frontal Sphenoid Zygomatic Maxilla Palatine Lacrimal Ethmoid
What is the nasal cavity constructed of?
It is constructed of bone and hyaline cartilage
What is unique about the hyoid bone?
They hyoid bone is the only bone in the body that does not articulate directly with another bone.
What are intervertebral discs composed of?
It’s the cushion like pad that is composed of two parts
nucleus pulposus and annulus fibrosus
what is nucleus pulposus?
its the inner gelatinous nucleus that gives the discs its elasticity and compressibility
what is annulus fibrosus?
it surrounds the nucleus pulposus with a collar composed of collagen and fibrocartilage
What is another name for C1 and C2?
Atlas and Axis
What is unique about C1?
it has no body and no spinous process
How many cervical vertebrae are there?
7
C1-C7
How many thoracic vertebrae are there?
12
T1-T12
How many lumbar vertebrae are there?
5
L1-L5
How many sacrum vertebrae are there?
5 fused
S1-S5
How many coccyx vertebrae are there?
4 fused
What is the bony thorax composed of?
the thoracic vertebrae dorsally, the ribs laterally, and the sternum and costal cartilages anteriorly
what is the shape classification of the sternum?
a daggered-shaped, flat bone
What are the 3 bones that fused together to make up the sternum?
the superior manubrium, the body and the inferior xiphoid process
Which ribs are true?
the superior 7 pair
Which ribs are false?
Ribs 8-10
Which ribs are floating?
Ribs 11 and 12
What is the axial skeleton?
80 bones segregated into 3 regions
skull
vertebral column
bony thorax
What is the appendicular skeleton?
it’s made up of the bones in the limbs and their girdles (pectoral and pelvic)
What is the shape classification of the clavicles?
slender, double curved long bones
What is the shape classification of the scapulae?
triangular, flat bones
What is the sole arm bone?
humerus
What bones form the forearm?
the radius and the ulna
Describe the articulation of the bones in the forearm with the humerus and carpals.
The radius and ulna articulate proximally with the humerus and distally with the wrist bones. They also articulate with each other proximally and distally at small radioulnar joints
Describe how the ulna and radius lie to one another. Which bone is longer?
The ulna lies medially in the forearm and is slightly longer than the radius.
The radius lies lateral to the the ulna.
How do the radius and ulna articulate with one another?
They articulate with each other proximally and distally at small radioulnar joints
How many bones make up the wrist?
8 bones
What are the bones that make up the wrist?
“Straight line to pinky, here comes the thumb”
going in a circle
Scaphoid Lunate Triquetral Pisiform Trapezium Trapezoid Capitate Hamate
Where do metacarpals radiate from and what do they form?
from the wrist to form the palm
In regards to the phalanges, what is unique about the thumb?
the thumb has no middle phalanx
What does the ilium form?
the superior region of the coxal bone
What does the ischium form?
the posteroinferior part of the hip bone
What does the pubis form?
the anterior portion of the hip bone
What is unique about the femur?
Describe how it articulates with the hip and tibia/fibula.
it’s the largest and strongest bone of the body
it articulates proximally with the hip and distally with the tibia and fibula
Where do you find interosseous membrane?
between the tibia and fibula, also between the radius and ulna
Explain articulations of tibia/fibula with femur and tarsals.
They articulate with the femur proximally and with the ankle bones distally
Describe how the tibia and fibula lie to one another.
the fibula is located laterally to the tibia
How many bones make up the ankle?
7 tarsals
What are the tarsal bones?
Tiger Cubs Need MILC
calcaneus talus cuboid navicular medial cuneiform intermediate cuneiform lateral cuneiform
Describe how the talus articulates with the tibia/fibula and calcaneus.
The talus articulates with the tibia and fibula superiorly and the calcaneus inferiorly
what does the calcaneus form?
the heel of the foot
