Osteoarthritis
Osteoarthritis (OA) is what you usually hear about when discussing joint pain. It is the most common cause of joint pain. Most people attribute OA to aging, but pintpoint the exact cause is not yet possible.

Exertion and overuse
Sprains and strains often cause joint pain for most Americans under 50. These usually occur when ligaments are stretched too far, or at times, tears. This is often an unnatural movement that leads to significant joint pain.

Acute Injuries, Fractures
When intense pressure is placed on the bone it can split. This is a fracture.
If more pressure is put on a bone than it can stand, it will split or break. A break of any size is called a fracture. Fractures, obviously, can cause joint pain.