Thanks for the question.
There are many possibilities.
Arthritis in the ankle, straining the other areas.
Clot in the leg: usually there would be swelling.
Artery problem in the leg.
Nerve pain from higher up: lower spine disc problems.
You need an exam to get an accurate diagnosis.
It is likely that physical therapy will help, regardless of the actual problem,
See an orthopedist or physical medicine doctor.
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