Blocked veins would cause swelling.
If she has swelling, I suggest venous dopplers before ted hose are used, to rule out clotting in the veins.
If there is no venous insufficiency and given the coolness, then this is something else..maybe small vessel disease, maybe a neurologic response from disease in the lower spine, also possible.
In that case, I would suggest an EMG/NCS test.
An MD of physical medicine and rehabilitation would be an excellent hands on evaluation at this point.
One must also consider autoimmune disease, such as lupus, or RA which can give this picture.
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