Is there a way to update just footer without updating Header

My document has Headers at the top of each page and a page number at the bottom. I want to update the page numbers on each page without makign any change in the headers. The headers were created in Word. When I try to update the page number using "Documents-> Header and Footer -> Update" it removes all the headers also on the page. If I try to use "Add" instead of update, it adds a new page number at the bottom. Is there a way to update just footer without making any changes in header?
 
I am using Acrobat Professional 9.4.6 and Windows vista machine