Arthritis literally means joint inflammation, but the term is often used to refer to a group of more than 100 rheumatic diseases that can cause pain, stiffness, and swelling in the joints. These diseases may affect not only the joints, but also other parts of the body, such as the supporting structures (muscles, bones, tendons, ligaments) and internal organs.
What Is Pain?
Pain is the body's warning system, alerting you that something is wrong. The International Association for the Study of Pain defines pain as an unpleasant experience associated with actual or potential tissue damage to a person's body. Specialized nervous system cells (neurons) that transmit pain signals are found throughout the skin and other body tissues. The neurons respond to injury or tissue damage. For example, when a harmful agent such as a sharp knife comes in contact with your skin, chemical signals travel from neurons in the skin through nerves in the spinal cord to your brain, where they are interpreted as pain.
Acute Pain or Chronic Pain
Most types of arthritis are associated with pain. There are two categories of pain: acute or chronic pain.
Acute pain is short-term, lasting a few seconds or longer, but it subsides as healing occurs. Examples of things associated with acute pain: burns, cuts, and fractures. Chronic pain, which is seen in people with osteoarthritis, rheumatoid arthritis, and other types of arthritis, can range from mild to severe and last weeks, months, years, or even a lifetime.