I did my medicals in the month of September 2016 for my work visa before coming to Canada. I have received my ITA now for PR processing. Will my medicals still be valid for submission or I need to take another medicals here?
Medicals are only valid for a year. So even if you don't re-do the medical now - you'll need to do it later (before you get the PR visa). I would re-do the medical now.