The Causes of Joint Pain

1. Osteoarthritis
Osteoarthritis (OA) is the most common joint disorder. Most of the time, the cause of OA is unknown. It is mainly related to aging, but metabolic, genetic, chemical, and mechanical factors can also lead to OA. The symptoms of osteoarthritis usually appear in middle age and almost everyone has them by age 70. Before age 55, the condition occurs equally in both sexes. However, after 55 it is more common in women. The disease causes the cushioning (cartilage) between the bone joints to wear away. As the disease gets worse, the cartilage disappears and the bone rubs on bone. Bony spurs usually form around the joint.


2. Unusual exertion or overuse, including Strains or Sprains
A sprain is an injury to the ligaments around a joint. Ligaments are strong, flexible fibers that hold bones together. When a ligament is stretched too far or tears, the joint will become painful and swell. Sprains are caused when a joint is forced to move into an unnatural position. For example, "twisting" one's ankle causes a sprain to the ligaments around the ankle.


3. Injury, including 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. If the broken bone punctures the skin, it is called an open fracture (compound fracture). A stress fracture is a hairline crack in the bone that develops because of repeated or prolonged forces against the bone. It is hard to tell a dislocated bone from a broken bone. However, both are emergency situations, and the basic first aid steps are the same. The following are common causes of broken bones:
• Fall from a height
• Motor vehicle accidents
• Direct blow
• Child abuse
• Repetitive forces, such as those caused by running, can cause stress fractures of the foot, ankle, tibia, or hip

4. Septic Arthritis
Septic arthritis is an inflammation of a joint caused by a bacteria infection other than gonorrhea. Septic arthritis develops when bacteria spreads through the bloodstream to a joint. It may also occur when the joint is directly infected with bacteria during injury or surgery. Acute septic arthritis tends to be caused by organisms such as staphylococcus, streptococcus pneumoniae and group B streptococcus. Chronic septic arthritis (which occurs less frequently) is caused by organisms such as Mycobacterium tuberculosis and Candida albicans. The knee and the hip are the most commonly infected joints.


5. Tendonitis
Tendinitis is inflammation, irritation, and swelling of a tendon, which is the fibrous structure that joins muscle to bone. In many cases, tendinosis (tendon degeneration) is also present. Tendinitis can occur as a result of injury, overuse, or with aging as the tendon loses elasticity. It can also be seen in systemic diseases such as rheumatoid arthritis or diabetes. Tendinitis can occur in any tendon, but some commonly affected sites are the shoulder, the wrist, the heel (Achilles tendonitis), and the elbow.


6. Autoimmune diseases such as:
   • Rheumatoid Arthritis
   Rheumatoid arthritis (RA) is a long-term disease that causes inflammation of the joints and surrounding tissues. It can also affect other organs. The cause of RA is unknown. It is considered an autoimmune disease. The body's immune system normally fights off foreign substances, like viruses. But in an autoimmune disease, the immune system confuses healthy tissue for foreign substances. As a result, the body attacks itself. RA can occur at any age. Women are affected more often than men. RA usually affects joints on both sides of the body equally. Wrists, fingers, knees, feet, and ankles are the most commonly affected. The course and the severity of the illness can vary considerably. Infection, genes, and hormones may contribute to the disease.
   
   
   • Lupus
   Lupus is an autoimmune disease. This means there is a problem with the body's normal immune system response. Normally, the immune system helps protect the body from harmful substances. But in patients with an autoimmune disease, the immune system can't tell the difference between harmful substances and healthy ones. The result is an overactive immune response that attacks otherwise healthy cells and tissue. This leads to chronic (long-term) inflammation. The underlying cause of autoimmune diseases is not fully known. Lupus affects nine times as many women as men. It may occur at any age, but appears most often in people between the ages of 10 and 50 years. African Americans and Asians are affected more often than people from other races.

7. Bursitis
Bursitis is inflammation of the fluid-filled sac (bursa) that lies between a tendon and skin, or between a tendon and bone. The condition may be acute or chronic. Bursae are fluid-filled cavities near joints where tendons or muscles pass over bony projections. They assist movement and reduce friction between moving parts. Bursitis can be caused by chronic overuse, trauma, rheumatoid arthritis, gout, or infection. Sometimes the cause cannot be determined. Bursitis commonly occurs in the shoulder, knee (washmaid's knee), elbow, and hip. Other areas that may be affected include the Achilles tendon and the foot. Chronic inflammation can occur with repeated injuries or attacks of bursitis.


8. Chondromalacia Patellae
Chondromalacia patella is the softening and degeneration of the tissue (cartilage) underneath the kneecap (patella). Chondromalacia patella that occurs in adolescents and young adults is thought to be related to overuse, injury, or too much force on the knee. It is more common in females. Many young people have a a slight problem with the position of the kneecap. Chondromalacia patella may also be a sign of arthritis of the kneecap, which is usually seen in older individuals. People who have previously had a dislocation, fracture, or other injury to the kneecap may be more likely to get chondromalacia.


9. Gout (especially found in the big toe)
Acute gouty arthritis is a sudden attack of pain in the joints, especially in the feet and legs, that occur when uric acid builds up in the joints. Gout is caused by an overproduction of uric acid or a reduced ability of the kidney to get rid of uric acid. The exact cause is unknown. It is more common in males, postmenopausal women, and people who drink alcohol.


10. Osteomyelitis
Osteomyelitis is an acute or chronic bone infection, usually caused by bacteria. The infection that causes osteomyelitis often is in another part of the body and spreads to the bone via the blood. Affected bone may have been predisposed to infection because of recent trauma.

11. Infectious diseases, including:
    • Epstein-Barr Viral Syndrome
    • Hepatitis
    • Influenza
    • Lyme Disease
    • Measles (Rubeola)