This task is tougher than it should be but I found an excellent reference which helps decipher how the windows ‘rename’ command interprets the wildcards ? and *. There are lots of examples to follow but I found the following works well in cases where you want to append a text field to a set of files without messing up the .jpg file type.
Example: rename the files called file1.jpg, file200.jpg to file1_edit.jpg, file2_edit.jpg.
>rename *.jpg ???????_edit.*
(where the number of ?’s equals the maximum characters before the ‘.’ in the files you want to rename).