I have fought the battle of the shoulder/clavicle, too many times to count. Both are wired together. Now I have a Defibrillator added to the shoulder joint. I would do the hammock as long as it did not pinch my shoulder. I am sure if your shoulder gets pinched you will be out of the hammock like a shot! I used my hammock when I was recoving from my last three surgeries. getting into the hammock was pure pain. Once I was down, had the ice machine going, I was comfortable. Here in the USA, we had small machines that circulate cold water through a pad that goes over the wound/sore place. Very helpful in the recovery process, you can go to sleep and have cold treatment while you sleep. Very helpful, and many surgeons recommed them. I am sure you know that you have to be very careful that your shoulder does not stiffen up to the point you can not use it. Clavicles can be difficlut to heal, so be very careful what you do. Bad form to break it again, before it is all the way healed. If you are under 35 it should heal well, if you have passed the 35 year mark, be prepared to take a little longer to heal.
I slept with many pillows, my neck hurt, my ribs hurt, I pretty much cocooned myself. I had to have help to get out of the hammock (okay I had to have help to move upon awakening). Very gently waking up muscles after sleep helps alot, no jumping up after laying still for a while.
I wish you a speedy and complete recovery.