How do you tell the difference between dvt and pain from saphenous vein valve not working? achy throbbing in l calf. better walking worse sitting.

Difficult to tell: DVT can cause pain or be completely painless. Saphenous vein insufficiency could be caused by DVT (called post-thrombotic syndrome). Therefore any pain or swelling should be investigated with an ultrasound to rule out DVT. If patient already has an established chronic DVT, the pain is likely caused by insufficient valves ( post-thrombotic syndrome)

DVT v venous reflux: DVT causes pain and there is swelling in the extremity. Unfortunately, the same symptoms occur with venous insufficiency but the symptoms in the latter are less in the morning, worse at night and more chronic in nature. Bottom line is: only way to determine for sure is to always get a Duplex vein scan to rule out DVT which is potentially dangerous. Venous insufficiency is not dangerous.