I recommend going to a vein specialist if you haven't been. Perhaps this is vascular. I have lumps under mine too and there are some "lumpy" vericose veins involved. I stood alot in my younger years in my jobs. They are not painful though. Have you tried support hose? I know, the weather is hot, but perhaps they will help you. This is what was recommended to me by my primary doctor. I am going to a vein specialist soon myself. I wish you the best on this.