I'm 7 weeks post hallux rigidus surgery/bone spur removal. Having a lot of burning on top of foot along with tightness and deep redness especially at?

Possible nerve issue. If you have had this feeling since the surgery sometimes the nerves in the skin are irritated. If it is new it could indicate infection or scar adhesions. If the redness is spreading out from your incision you should follow up with the surgeon as you may need antibiotics. If the scar is tight and skin is immobile you can do circular massage or use scar creams.