Some swelling IS normal even at this point, but if your ankle is starting to show signs of swelling it's time to call your surgeon and ask about the possibility of a blood clot.
Doctor's call these DEEP VENOUS THROBOSES, and they can be quite dangerous if not diagnosed and treated quickly. THIS LINK HERE IS A GOOD ONE FOR YOUR INFORMATION.
A blood clot in the calf could cause some swelling, so this is definitely on the list. The diagnosis is made by ultrasound. I think it would be very wise to call your surgeon about this or the on-call surgeon, and let them know about this. If you can't get anyone I recommend seeing your doctor as soon as you can tomorrow, or, if that is not possible, I recommend going to a good Urgent Care clinic or even the ER.
If you develop chest pain or shortness of breath I advise going to the ER
I'm not trying to scare you, I'm just telling you that while this could be a normal part of recovery, a blood clot can happen after surgery and you should definitely get this looked at as soon as you can.
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