Is there a way to access a row in the main viewer with the keyboard?

I use a hand-held air mouse because of arm & shoulder issues, so it is awkward to constantly move back & forth between the my mouse and keyboard. In the main Calibre viewing area, I can use my arrow keys to move up and down between rows, or even left & right between columns, but I can't figure out how to access those fields without using my mouse & clicking on them. Is it possible & I'm missing it? If it's not, how hard would it be to add that feature?