Once again, GOUT, from gout.com:
The pain of gout (called attacks or flares) is caused by inflammation when needle-like crystals are deposited in connective tissue and/or in the fluid that cushions a joint (the synovial fluid). These crystals are made up of uric acid, a substance produced when the body breaks down purines found in human tissue and many foods we eat. Most uric acid is carried through the bloodstream to the kidneys, which eliminate it from the body in the urine. However, if the body produces too much uric acid or if the kidneys don't eliminate enough of it, uric acid can build up in the blood. This condition is called hyperuricemia and can lead to gout attacks in some cases. However, in most cases, hyperuricemia does not lead to gout.
An attack usually starts with sudden, severe pain, tenderness, redness, warmth, and swelling in the large joint of the big toe. Other joints may include the instep, ankles, heels, knees, wrists, fingers, and elbows. Rarely, the shoulders, hips, or spine may be affected. After about 3-10 days, the attack usually subsides, and the next one may not happen for months or even years. But over time, the gout attacks can become more severe, last longer, affect more than one joint, and occur more often.