Can anyone suggest some good exercises for arms and shoulders that don't involve weights? I have rotator cuff impingement on both sides, so the exercises can't involve any sudden outward thrusting movements, either.

Can you do body weight exercises? Things like planks and pushups? You can take a lot of the pressure off with push ups if you go onto your knees, or do them standing up against the wall!

Oh, that's a great idea. I'm going to do pushups against the wall while watching TV tonight. Pushups hadn't occurred to me. It's so good to hear the creative ideas that people here have to share.

Stand tall, your muscles tight along the length of your arms, and your arms straight out to the sides. Gently move your arms in circles around your shoulders, maintaining them straight and your elbows tensely locked. 3 sets of 10–20 repetitions in each direction should be completed.