Thumb fever mainly refers to the thumb of the skin temperature rise, accompanied by swelling and discomfort, common causes are as follows: 1, bacterial infection of the thumb, due to the hand in the daily work and study is the most used parts, so it is easy to cause trauma. Due to ingrown nails or onychomycosis of the nails, it can also cause bacterial invasion, which can produce bacterial infection of the thumb and fever of the thumb.2. Seen in gout, due to the characteristics of gout, it can lead to increased blood uric acid in the body, and blood uric acid will be deposited around the thumb joints to produce gouty arthritis, which can lead to inflammatory skin temperature, swelling and even pain.3. Sterile inflammation of the thumb such as Rheumatoid arthritis or thumb strain or injury. If this situation occurs, it is recommended to go to the hospital in a timely manner, after a clear diagnosis to take appropriate treatment.