ARTHRITIS
**Osteoarthritis = most common...it occurs when the cartilage in the knee wears away. This
can be caused by excess stress on the joint by recurring injuries. Mostly affects middle aged or older people.
**Rheumatoid arthritis = this destroys the knee cartilage and is more common in younger people.
TENDINITIS
**Often called the "jumper's knee."
**Occurs when you overuse your tendons like running, jumping, or cycling.
TORN CARTILAGE
**This can happen by a sprain or trauma to the knee.
SPRAINED OR STRAINED KNEE LIGAMENTS OR MUSCLES
**Usually caused by a blow to the knee or a sudden twist of the knee.
