Bouts of warmth on the back of the feet may be suffering from gout, vascular lesions in the lower limbs, sprained ankles, etc. 1. Gout: When gout attacks in the acute stage, it may lead to fever and pain on the back of the feet, redness and swelling of the skin on the back of the feet, and even affect walking. It is recommended to go to the hospital for a clear diagnosis. 2. Lower extremity vascular lesions: Commonly, there are lower extremity venous embolism, which affects the blood return of the lower extremity, and can cause pain in the lower extremity, and the back of the foot can be hot and painful. 3. Ankle sprains: when ankle sprains, it can lead to localized redness, swelling, pain and fever on the back of the foot, you can choose hot compresses to promote blood circulation and help recovery, and seek medical treatment if necessary. The back of the foot paroxysmal fever, it is recommended to go to the hospital in a timely manner, the lower extremity vascular ultrasound examination, to clarify the presence of vascular disorders.