Are both the legs painful? Since when? Any swelling or edema of the legs?
How large is the indentation? Did you get hurt at any time? Is the skin discoloured over the indentation? Is the indentation more painful than the other parts of the leg?
Are you on HRT or any other medicine? Do you have diabetes?
From the description of the pain, it sounds possible that it could be the result of a blood clot blocking a vein in your leg. Especially since sitting makes it worse.
The indentation could be a localised contraction of the muscle due to a lack of blood supply.
A test for the presence of a substance called D-dimers can rule out or confirm the presence of blood clots.
Another possibility for the pain as well as the indentation could be pinching of the sciatic nerve in the thigh. The pain in this case will also be similar to what you have now. The nerve could also cause contraction of the muscle and the indentation. Tests for nerve conduction as well as muscle conductivity can usually diagnose sciatic nerve pain.
You need a physical check up, blood tests and other investigation for a proper diagnosis.
I hope this helps.
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