The skull is one of the major components of the axial skeleton. Name the other two.
Vertebrae and bony thorax
What are four major sutures of the skull, and what bones do they connect?
Sagittal- two parietal bones
Coronal- parietals meet frontal bone
Squamous- temporal meets parietal
Lambdoid- temporal meets parietal
Name the eight bones composing the cranium.
Frontal, Ethmoid, Right temporal, Left temporal, Sphenoid, Right parietal, Left parietal, Occipital
Give two possible functions of the sinuses.
Lighten facial bones; act as resonance chambers for speech
Why can the sphenoid bone be called the keystone of the cranial floor?
The sphenoid boe forms a plateau across the width of the skull.
Superior and medial nasal conchae are part of this bone
Its "holey" plate allows olfactory fibers to pass
Its oval shaped protrusions articulate with the atlas
Spinal cord passes through a large opening in this bone
Are the same skull bones seen in the adult also found in the fetal skull?
No, some areas still remain to be converted to bone.
How does the size of the fetal face compare to its cranium? How does this compare to the adult skull?
Face is smaller
Adult skull is 1/8th total body length whereas the fetal skull is 1/4th total body length
What are the outward conical projections in some of the fetal cranial bones?
These are ossification centers.
What is a fontanel? What is its fate?
Fibrous membranes between the bones of a fetal skull becomes bone by 22 months.
What is the function of the fontanels in the fetal skull?
Allows skull to be compressed during birth and allows for brain growth during late fetal life.
Bear facets for articulation with ribs; form part of bony thoracic cage
Twelve components; unfused
Vertebra with block like body and short stout spinous process
Five components; unfused
What is a herniated disc? What problems might it cause?
A slipped disc; protruding cartilage from vertebra.
Pain and numbness
Why is the clavicle at risk to fracture when a person falls on his or her shoulder?
It is a slender bone.
Why is there generally no problem in the arm clearing the widest dimension of the thoracic cage?
The clavicle serves as a brace to hold the arm away from the top of the thorax.
Compare the pectoral and pelvic girdles in terms of flexibility, security, and ability to bear weight.
Flexibility: pectoral- more flexible
Security: Pelvic- more secure
Weight-bearing ability: pelvic- able to bear weight
What organs are protected, at least in part, by the pelvic girdle?
Reproductive organs, urinary bladder, and part of the large intestine
Distinguish between the true pelvis and false pelvis.
False pelvis- superior; supports abdominal viscera
True pelvis- inferior; limits delivery of baby
4 steps of bone repair.
1. Hematoma forms
2. The break is splinted by a fibrocartilage callus
3. The bony callus forms
4. Bone remodeling occurs
forms the forehead, the bony projections under the eyebrows and the superior part of each eyes orbit
Body or centrum of vertebra
disclike, weight bearing part of the vertebra facing anteriorly in the vertebral column
arch formed from the joining of all posterior extensions, the laminae and pedicles, from the vertebral body
Superior and inferior articular processes
paired projections lateral to the vertebral foramen, allowing a vertebra to form joints with adjacent vertebrae
bone ends are connected by cartilage, amphiartrotic joints- spinal column, ribs, and pelvis
joints in which the articulating bone ends are separated by a joint cavity containing synovial fluid
broken bone ends are forced into each other
commonly occurs when one attempts to break a fall with outstretched arms