1. Bone Fractures

2. Homeostatic Imbalance
Despite their remarkable strength, bones are susceptible to fractures, or breaks, all through life.
Most fractures result from trauma that twists or smashes the bones.
In old age, bones are thin and weak. Hereby, fractures occur more often.

3. Open and Closed Fractures
A fracture in which the bone breaks clearly but does not penetrate the skin is a closed (or simple) fracture.
When the broken bone ends penetrate through the skin, the fracture is open (or compound).

4. Reduction
A fracture is treated by reduction. Reduction is the realignment of the broken bone ends.
Closed reduction: the bone ends are coaxed back into their normal position by the physician’s hands.
Open reduction: the bone ends are secured together with pins and wires through the surgery.
It takes 6 to 8 weeks for the fracture to heal. The number is different for larger bones and for older people’s bones.

5. The repair of bone fractures
The repair of bone structures involves four major events:
1. A hematoma is formed.
Blood escapes from ruptured blood vessels and forms a hematoma. All of the cells within the hematoma degenerate and die.

6. 2. The break is splinted by a fibrocartilage callus.
There is a growth of new capillaries (granulation tissue) into the clotted blood at the site of the damage point. Also, there is disposal of dead tissue by phagocytes.
Connective tissue cells of various types form a mass of repair tissue, the fibrocartilage callus.
Fibrocartilage callus contains some cartilage matrix, some bony matrix, and collage fibers.
It takes care of the broken bone and closes the gap.

7. 3 .The bony callus is formed.
The fibrocartilage callus is replaced by a spongy bone, the bony callus.
The bony callus is a deposit formed between and around the broken ends of a fractured bone during normal healing.

8. 4.Bone remodeling occurs
Bone cells called osteoclasts begin the process of bone remodeling by dissolving the bone. Bone cells called osteoblasts then synthesize the new bone in order to replace the resorbed bone.

9. Axial Skeleton

27. Homeostatic Imbalances

28. Fractures Fractures are breaks in the bone
During youth most fractures result from exceptional trauma that twists or smashes bones
In old age, bones thin and weaken, and fractures occur more often
A fracture in which the bone breaks cleanly but does not penetrate the skin is a closed or simple fracture
When the broken bone ends penetrate through the skin, the fracture is open or compound

29. Herniated Discs
Drying of the discs, along with a weakening of the ligaments of the vertebral column, predisposes older people to herniated discs or slipped discs
Herniation may also result when the vertebral column is subjected to exceptional twisting forces
If the protruding disc presses on the spinal cord or the spinal nerves exiting from the cord, numbness and excruciating pain can result

30. Rickets
Rickets is a disease of children in which the bones fail to calcify
As a result, the bones soften and a definite bowing of the weight-bearing bones of the legs occurs
Rickets is usually due to a lack of calcium or vitamin D in the diet (vitamin D is needed to absorb calcium into the bloodstream)
Rickets is not common in the USA where foods are fortified with vitamin D and most children drink enough calcium-rich milk
However, it can happen in infants nursed by mothers who become vitamin D- deficient over the course of a long gray winter

31. http://www.spine-health.com/video/lumbar-herniated- disc-video

32. Scoliosis A
May be congenital (present at birth) or result from disease

33. Kyphosis

34. Lordosis