upper body workouts w/ a broken clavicle?

is there anything i can do without aggrivating the injury? its been 6 weeks but there isnt much tissue holding the 2 ends of the bone together. my left arm has shrunk considerably and i'd like to start working with light weights to prevent any further depletion. i was doing bicep curls the other day w/ just some 20lb weights and there was not any pain, but that doesnt necesarily mean i wasnt causing damage. is there anything i can do that will be safe for it or will i just have to sit it out and wait until its fully healed?