Bone is not a stagnant organ. It is the body's reservoir of calcium and is always undergoing change under the influence of hormones. Parathyroid hormone increases blood calcium levels by leeching calcium from bone, while calcitonin has the opposite effect, allowing bone to accept calcium from the blood.
What causes a fracture?When outside forces are applied to bone it has the potential to fail. Fractures occur when bone cannot withstand those outside forces. Fracture, break, or crack all mean the same thing. One term is not better or worse than another. The integrity of the bone has been lost and the bone structure fails.
Broken bones hurt for a variety of reasons including:
- The nerve endings that surround bones contain pain fibers and and these fibers become irritated when the bone is broken or bruised.
- Broken bones bleed, and the blood and associated swelling (edema) causes pain.
- Muscles that surround the injured area may go into spasm when they try to hold the broken bone fragments in place, and these spasms cause further pain.
Fractures can occur because of direct blows, twisting injuries, or falls. The type of forces on the bone may determine what type of injury that occurs. Descriptions of fractures can be confusing. They are based on:
- where in the bone the break has occurred,
- how the bone fragments are aligned, and
- whether any complications exist.
Next, there needs to be a description of the fracture line. Does the fracture line go across the bone (transverse), at an angle (oblique) or does it spiral? Is the fracture in two pieces or is it comminuted, in multiple pieces?
Finally, the fracture's alignment is described as to whether the fracture fragments are displaced or in their normal anatomic position. If the bones fragments aren't in the right place, they need to be reduced or placed back into their normal alignment