Zhang Daniang is 70 years old and has varicose veins in her lower limbs for more than 30 years, but she has not been particularly uncomfortable and did not care. Recently, there are a lot of things at home and she was busy, so suddenly one day she had redness and pain at the knee joint and could not move. There was never this phenomenon before, so the dame was very nervous and came to the hospital for consultation. After careful examination, the doctor diagnosed saphenous varicose vein with thrombophlebitis. Why does thrombophlebitis occur in saphenous varicose veins? This is because varicose vein patients have a slow blood return and tend to have blood clotting in the vessels where varicose veins are evident. The blood clots irritate the vessel walls and become red, swollen, painful and can be felt. This condition is common in patients with varicose veins and is not a cause for concern. In most patients, the pain and redness will subside after a week with heat or physical therapy and elevation of the lower extremities, and surgery is not required. For patients with frequent thrombophlebitis, surgical treatment of varicose veins can be considered after the thrombophlebitis is controlled, which can reduce the recurrence of thrombophlebitis.