I have my roundoff back handspring (but i go crooked) i cant do a standing back handspring or a front handspring because my left arm wont squeeze tight beside my ear. My right arm squeezes tight beside my ear but my left arm wont do it. Some times it hurts also. My coach says it may be my rotator cuff that is causing it. Is there any other possible reasons for this? What can i do to fix it?