Hai, Thanks for writing in, In your case the causes for discoloration of your foot may be one of the following 1. Usually a dry, scaly and high pigmentation of the skin is present after any casting. This is normal and the skin turns to normal in a weeks time once it gets exposed to adequate humidity, 2. Injuries around ankle stretch the skin and sometimes compromise their vascularity. This may cause discoloration and poor wound healing at times. But again, if there are no signs of infection, this may also become normal, 3. As such DVT doesnt causes discoloration. But due to secondary venous stasis and prolonged edema, the skin may become dark. This venous stasis needs adequate elevation of limb, ankle mobilisation and measures to control and prevent edema from developing, 4. Sometimes due to coumadin, there might be increased bleeding in the local site which can cause hyperpigmentation. These needs titration of the dose of coumadin. But since your INR is normal, this possibility is rare. So, to find out the exact cause for discoloration, a proper clinical examination of your foot is needed. I would suggest you to consult your doctor and follow his advise. Get well soon.