Brief Answer:
Pitting edema - prolonged standing can cause it.

Detailed Answer:
Hi,
Thanks for asking.
I am Dr. Prakash HM and I will be answering your query.
Based on your query, my opinion is as follows:

1. Whenever we look at edema in the ankle and legs, we first verify whether it is pitting or nonpitting. Pitting means, when you apply pressure in the swelling area, it forms a pit and then it becomes normal swelling like before within a few minutes. Non-pitting usually it won't go down/ form a pit. Non-pitting is usually due to lymphatic blockage and at present, i do think you have it.
2. As it is pitting edema, it is due to fluid/ water retention. It usually occurs on prolonged standing or sitting without movement. This is dependent swelling.
3. Main reason for fluid retention is inadequate or reduced flow through the veins of the legs. Fault could be in vein valves or reduced activity of the muscles in the calves in legs (The calf muscles function in moving the blood up, back to the heart - these calf muscles are also called as peripheral heart)
4. On prolonged standing or sitting, as these calf muscles do not perform, it can result in limb/ ankle edema. There is increased blood in veins, so, increased pressure in veins, resulting in fluid movement outside into tissues, which is resulting in edema.
5. Other causes of pitting edema include failure of vein valves (varicose veins), low protein in blood (hypoproteinemia) and pressure on veins due to mass in abdomen (affecting flow of blood back to the heart, like in pregnancy - the pregnant enlarged uterus pressing on pelvic veins)
6. Compression socks perform the same function of calf muscles and it helps in improving venous return. Also, elevation of the legs, above heart level - during sleep/ lying down position - put pillows below legs - this could help in reducing swelling.

Hope it helps.
Any further queries, here to help again.

Dr. Prakash HM

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