Redness, swelling and hard lumps in the calves may be thrombophlebitis, localized infection, salpingitis, trauma, skin allergy, insect bite dermatitis and so on. 1. Thrombophlebitis: due to the formation of thrombus in superficial veins, there will be localized hard lumps, obvious redness and swelling around the thrombus, dark blood vessels can be found through the skin, accompanied by obvious pain, and most of them are suffering from varicose veins of the great saphenous veins. 2. Localized infection: If the skin is infected, there is obvious redness and swelling of the local skin, hard lumps, the skin temperature can be increased, and even secretions. 3. Danovirus: it is an acute inflammatory infection of the lymphatic network of the skin, mostly caused by B hemolytic streptococcus infection. 4. Trauma: If the local skin is squeezed or hit to cause trauma, there will be swelling of the soft tissues of the skin, pain, red color. 5. Skin allergy: if contact with special goods, drugs, etc., may cause skin allergy, there will also be redness and swelling with hard lumps, localized visible wind, accompanied by itching. 6. Insect bite dermatitis: mostly occurring in the summer and fall seasons, insect bites with skin lesions accompanied by itching, also belongs to the allergic reaction. Calf redness and swelling with hard lumps, timely to the hospital to do an ultrasound examination to determine the specific cause of the disease and then treatment.