This is a similar pose to what lemoncustard is describing above, but using the wall. I do a lot of down dogs for my stress headaches and sometimes my head hurts so much I can't do a down dog. I then do a modified version of it by standing with the palms on the wall and having my torso parallel to the floor, this provides many of the benefits of down dog without the pain - either of the head or the shoulder..
Good luck..
Elle