nah, that's probably because of the constant pressure they put on him throughout his entire career. not so easy to score when everyone is doubling you and no one else on the team is a reliable scorer from the perimeter.
"Kobe first injured this shoulder in the preseason, according to sources. Has been playing w/ it all year. It just got worse last night"
After suffering the injury, he simply started shooting with his left hand rather than leaving the game.