A joint is the location where two bones meet. Arthralgia is the medical term for pain in these joints.

Joints are structures consisting of bone, muscles, synovium (a thin layer of tissue that lines the joint space), cartilage and ligaments. They are designed to bear weight and help the body move.  The many types of joints include the temporomandibular joint in the jaw, facet joints and intervertebral joints in the spine, the shoulders, the elbows, the wrists, the fingers, the hips, the knees, the ankles and the toes.

Most joints are synovial, lubricated by synovial fluid to ease movement. These joints allow varying degrees of movement, ranging from the mobility of the shoulder (a modified ball and socket) to the flexion and extension (bending and straightening) of the hinged distal interphalangeal joints in the fingertips. Some other synovial joints, such as those in the spine, permit limited movement. Fixed joints, such as those in the skull, are fused and do not allow movement.

Most people experience joint pain at some point in their lives. Patients can experience pain in either one joint or many joints. When patients experience pain in more than four joints, it is called polyarticular joint pain.

Patients may experience joint pain that is acute (a normal response to disease or trauma, sometimes defined as lasting less than six weeks), subacute or chronic (pain that persists after the cause’s expected resolution or is due to a chronic condition, sometimes defined as lasting three months or longer). Others experience pain only during certain physical activities.

Some patients can experience morning stiffness because immobility during sleep worsens some types of joint pain. Other kinds of joint pain are worsened by activity.

Arthralgia is different from arthritis, a common condition affecting 66 million Americans, or 1 in 3 adults, according to the Arthritis Foundation. Arthritis is the nation’s leading cause of disability, according to the U.S. Centers for Disease Control and Prevention (CDC).

Arthralgia is joint pain without inflammation, whereas many forms of arthritis do involve inflammation. However, joint pain is a common symptom for arthritis. It is important to note that osteoarthritis, the most common form of arthritis, does not involve systemic inflammation but does cause joint pain.

Experiencing joint pain does not usually constitute a medical emergency. However, if it is accompanied by certain symptoms, it can be indicative of an infection or other condition that may require immediate medical attention. Patients should contact a physician if:

• Joints are hot or swollen
  
  
• Joint pain is accompanied by fever, weight loss or malaise (a general feeling of discomfort, illness or lack of well-being)
  
  
• Joint pain is accompanied by a burning pain or paresthesia (sensation of tingling, pricking or numbness of the skin)