Test 4 Module 7 Flashcards
What are fractures?
cracks or breaks in bones caused by physical stress
What are the 3 ways fractures are categorized?
- By external appearance
- Their location
- The nature of the damage to the bone
What is a closed fracture?
A fracture that does not break through skin
What is a open fracture?
A fracture that does break through skin
What are the 4 basic steps bone repair are broken into?
- Hematoma (blood clot) formation
- Fibrocartilaginous callus formation
- Bony callus formation
- Remodeling
What are the 4 steps of bone repair are broken into in depth?
- Hematoma (blood clot) formation: A mass of clotted blood forms at fracture site. Bone cells begin to die. Tissue becomes swollen, painful, and inflamed
- Firocartilaginous callus formation: Capallaries grow into the area and macrophages clean up debris. Fibroblasts and osteoblasts migrate to the area from periosteum. The fibroblasts become chondrocytes which make cartilage n some areas of fracture. Osteoblasts begin forming spongy bone in other areas of fracture. The repair tissue now consists of both cartilage and spongy boine and is called the fibrocartliginous callus.
- Bone callus formation: Osteoblasts remove the cartilage from fracture site and convert the fibrocartilage callus to a hard bone callus entirely of spongy bone. This begins 3-4 weeks per injury and continues until a firm union forms 2-3 months later.
- Remodeling: remodeling occurs during bony callus formation and continues for several months after the bony callus has formed. (remodeling can take years to finish completely) Excess material outside the shaft is removed. Osteoclasts remove excess bone and any spongy bone that needs to be replaced with compact bone. Osteoblasts lay down compact bone to reconstruct the shaft. The final structure resembles unbroken bone, although sometimes there is a slight swelling at location of original fracture.
How do infant bone fractures heal?
They heal without intervention sue to muscle contractions and tissue growth that together move the bone frags back into place, like a mechanical jack
What are the 4 steps of infant bone fractures?
- clot forms at fracture
- the fibrocartliginous callus forms at the fracture site
- Growth of tissue on one side provides force to realign the bone frags
- The bony callus forms allowing bone to heal
What is a callus?
any mass of cells
When an infant is born the skull bones haven’t finished ______, especially those of the _____?
forming and Cranium
Some of the cranial bones in an infant are in pieces and haven’t yet even _______ ?
combined to form a single bone yet
What is the cranium?
the brain case
The cranial bones form by _____?
intramembraneous ossification
What do all of the cranial bones start out as?
Flexible fibrous connective tissue proper
Cranial bones start out entirely composed of a _____ and undergo intramembranous ossification to convert to bone?
flexible fibrous connective tissue proper
The flexible fibrous connective tissue left in the cranium at the time of birth will continue undergoing intramembranous ossification to finish converting to _____?
bone
Once all cranial bone has formed, dense connective tissue proper will be used to create _____ that bind all the cranial bones?
sutures
What is the line of junction or an immovable joint between 2 bones, especially of the skull?
suture
How many sutures are in the head?
3
What are the fontanels?
At birth they are the remaining sections of flexible fibrous connective tissue proper that have not yet converted to bone
Why do babies need fontanels?
They allow the skull to flex during birth which can be important while traveling down the birth canal and this is can result in “football head” after birth
_____ aren’t all the flexible fibrous connective tissue in the cranium, but are the largest, most detectable areas of it?
Fontanels
What are the 4 fontanels?
- Anterior fontanel
- Occipital fontanel
- Sphenoidal fontanels
- Mastoid fontanels
What are the 2 fontanels that last around 2 years?
Anterior fontanel and the occipital fontanel