Fractures & Bone Remodeling Flashcards
(20 cards)
Simple Fracture
Closed Fracture
A fracture that breaks cleanly and does not penetrate the skin
Compound Fracture
Open Fracture
Broken ends of the bone protrude through the soft tissue and the skin
Very serious and can cause bone infections
Comminuted Fracture
Bone breaks into many fragments
Common in the elderly because the bones are much more brittle
Compression Fracture
Bone is crushed
Common in porous bones (Osteoporosis)
Depressed Fracture
Broken bone portion is pressed inward
Typical in skull fractures
Impacted Fracture
Broken bone ends are forced into each other
Common in falls and when one attempts to break a fall
Spiral Fracture
Ragged break
Occurs when excessive twisting forces are applied to a bone
Common in sports fractures
Greenstick Fracture
Bone breaks incompletely
Common in children because their bones are softer and more flexible than adult bones
Avulsion
Ligament pulls a bone fragment after from the bone
Normally considered a bad sprain
Found at joints
Closed Reduction
The bone ends are coaxed back into their normal position by the physician’s hands
Open Reduction
Surgery
The bone ends are secured using wires and pins
What are the four major events of the repair of a bone fracture?
- A Hematoma Forms
- A Fibrocartilage Callus Forms
- The Bony Callus Forms
- Bone Remodeling Occurs
How long is the healing time for a simple fracture?
6-8 weeks
What determines how long the healing time for a fracture is?
How large the bone is and if the person is old (they have poor circulation)
After the bone is reduced what happens?
It is immobilized by a cast or traction to allow the healing process to begin
What is reduction?
The realignment of the broken bone ends
A Hematoma Forms
Blood vessels are ruptured when the bone breaks
As a result a blood-filled swelling occurs
Bone cells deprived of nutrition die
A Fibrocartilage Forms
Early event of bone repair is the growth of new capillaries into the clotted blood at the site of the damage
phagocytes dispose of the dead tissue
Connective tissue cells of various types form a mass of repair tissue
Fibrocartilage callus that contains several elements acts to “splint” the broken bone, closing the gap
- Cartilage matrix
- Bony matrix
- Collagen matrix
The Bony Callus Forms
fibrocartilage callus is replaced by the bong callus because more osteoblasts and osteoclasts migrate into the site of the fracture and multiply
Bone Remodeling Occurs
Over a few weeks to months, depending on the bones size and site of the break
The bony callus is remodeled in response to the mechanical stresses placed on it, so that it forms a strong, permanent “patch” at the fracture site
