What causes my foot to react to cold with extreme pain i do have scar tissue , altered feeling in this foot and suffer from chronic pain from surgery?

Raynauds?: Raynaud's is disorder where there is a severe constriction or spasm of the arteries to the hands or feet. Classically the digits turn white then blue and then red. The red comes after the blood vessels open back up. There is often pain associated with this, too. This phenomena happens with cold exposure. Your doctor would be able to figure this out.

Neuropathic/vascular: Sounds like a neuropathic condtion, possibly as a result of trauma that has occurred. May also be the result of vascular/circulatory condition, also possibly from trauma.

Cold: This is a description of raynaud's syndrome. It may coincide with surgery but may not, too. See your surgeon for the chronic pain. Good luck.