Blood clots. At times, veins deep inside the legs get larger. They may cause leg ache and swelling. Request health-related support for ongoing leg ache or swelling. This will necessarily mean a blood clot. As per this journal short article "Chronic venous insufficiency (CVI) on the reduced legs might cause https://www.sgvascularctr.com/what-surgery-is-available-for-varicose-veins/