A joint is a place where 2 bones meet, connected by one or more ligaments. The ends of the bones are covered by cartilage, which allows the 2 bones to move simply. The joint is surrounded by a capsule that defends and supports it. The joint capsule is lined with a type of tissue called synovium, which creates synovial fluid, a clear substance that lubricates and nourishes the cartilage and bones inside the joint capsule.

Here are the 3 primary causes of joint pain:

1. Arthritis - Arthritis exactly means inflammation of one or more joints. Arthritis causes pain, stiffness and swelling in the joints. Arthritis is classified as one of the rheumatic diseases. These are conditions that are different individual illnesses, with differing features, problems and treatments. They are alike in that they have a tendency to affect the joints, muscles, ligaments, cartilage and tendons, and many have the potential to affect other interior parts of the body. There are more than 100 different types of arthritis. Together, the many types of arthritis make up the most general chronic sickness in the United States. The causes of arthritis depend on the form of arthritis. Causes involve injury, metabolic abnormalities (like gout), hereditary factors, infections and uncertain reasons. The 2 most general types of arthritis are osteoarthritis and rheumatoid arthritis.

2. Tendonitis - Tendonitis is inflammation of a tendon. A tendon is fibrous tissue that connects a muscle to a bone. Tendons transmit the pull of the muscle to the bone to cause movement. Tendons can be little, like those found in the hand, or large, like the Achilles tendon in the heel. Tendonitis is most frequently the result of a repetitive injury in the affected area. Tendonitis occurs more frequently with age as tendons become less flexible and more prone to injury with age. People who perform activities that require repetitive motions or place stress on joints are at higher risk for tendonitis.

3. Bursitis - Bursitis is inflammation of a bursa. A bursa (the plural form is bursae) is a little, fluid-filled sac that acts as a cushion between a bone and other moving parts like muscles or tendons. Bursae are found throughout the body. Bursitis occurs when a bursa becomes inflamed from injury, infection or owing to an underlying rheumatic condition. Bursitis is usually caused by overuse or direct trauma to a joint and it frequently occurs in the knee, shoulder or elbow. People who perform activities that require repetitive motions or place stress on joints are at higher risk for bursitis.