When uric acid production increases or excretion decreases, the concentration of uric acid in the blood rises to saturation values and urates form crystals that deposit and collect directly around the joints and soft tissues of the foot, where the body’s cells interact with the urate crystals and release inflammatory factors and proteases, thus causing inflammatory damage to the joints.
Patients will have a sudden onset of disease at some point, with symptoms of redness, swelling, heat and pain in the invaded joints of the foot, manifesting as swelling and pain in the back of the foot.