1. Notes 4: Types of Fractures
Skeletal System
Notes 4: Types of Fractures

2. Types of Fractures: Two Main Types- Open & Closed
1. Open Fractures- Also called a Compound Fracture
A fracture in which the bone breaks through the skin

3. 2. Closed Fractures:
A closed fracture is when the bone breaks but there is no puncture or open wound in the skin

4. Types of Closed Fractures:
Greenstick fracture: an incomplete fracture in which the bone is bent. This type occurs most often in children.
Transverse fracture: a fracture at a right angle to the bone's axis.
Oblique fracture: a fracture in which the break has a curved or sloped pattern.
Comminuted fracture: a fracture in which the bone fragments into several pieces.

6. Bone cells that aid in remodeling
Osteoblast
Builds new bone
Mature bone cell
Osteocyte
OsteoblastsOsteoblasts are responsible for building new bone and lie at the centre of bone physiology. Their functions include the synthesis of collagen and the control of mineralisation.
OsteoclastsOsteoclasts are specialised cells that resorb bone. They work by sealing off an area of bone surface then, when activated, they pump out hydrogen ions to produce a very acid environment, which dissolves the hydroxyapatite.
OsteocytesBone adapts to applied forces by growing stronger in order to withstand them; it is known that exercise can help to improve bone strength. Osteocytes are thought to be part of the cellular feed-back mechanism which directs bone to form in the places where it is most needed. They lie within mineralised bone and it is thought that they may detect mechanical deformation and mediate the response of the osteoblasts.
Osteoclast
Eats bone

7. Natural Repair of Fractures
hematoma
callus
bony callus
bone
remodeling

8. Other Forms of Bone Repair:
Electrical stimulation of the fracture site:
Increases speed and completeness of healing
The e- stimulation inhibits PTH and slow osteoclasts down from reabsorbing bone
2. Ultrasound treatment:
Daily treatments reduce healing time of broken bones by 25-35%
3. Free vascular fibular graft technique:
Transplant fibula in arm
Gives good blood supply not available in other treatments
4. Bone substitutes:
Crushed bone from cadaver- but risk of HIV and hepatitis
Sea bone- coral
Artificial bone- ceramic