I also have shoulder problems from a lifting injury, so I can relate.
I usually bring the bar to within 2 inches of my chest. I feel this is a good compromise, I decrease the chances of a shoulder injury, and it makes you use perfect for because you can't bounce the weight off your chest.
I've heard the 90 degree rule but, I feel the 2 inches works just fine.
I do use the 90 degree rule for my Military Presses, Lateral shoulder lifts, and Tricep pushdowns.



Reply With Quote
) so for me going to only 90 is going to mean there's more than 6" between my chest and the bar. 
