Joint pain can be caused by injury affecting any of the ligaments, bursae, or tendons surrounding the joint. Injury can also affect the ligaments, cartilage, and bones within the joint. Pain is also a feature of joint inflammation (arthritis, such as rheumatoid arthritis and osteoarthritis) and infection, and extremely rarely it can be a cause of cancer of the joint. Pain within the joint is a common cause of shoulder pain, ankle pain, and knee pain. Joint pain is also referred to as arthralgia. The sexually transmitted diseases (STDs) chlamydia and gonorrhea can lead to joint pain.

Symptoms and signs associated with joint pain can include

• joint redness,
• joint swelling,
• joint tenderness,
• joint warmth,
• limping,
• locking of the joint,
• loss of range of motion of the joint,
• stiffness,
• weakness.

Source: http://www.rxlist.com