I was born with a birth defect in my left arm which causes me not to be able to turn it completely over so my palm is flat facing up. This lack of flexibility causes me not to be able to put necesary pressure on the E string sometimes and causes my fingers to be flatter instead of curved on the fretboard. This makes my technique more than occasionally sloppy the higher I go and when I have to reach in any direcion. I really can't play with a 4th finger on the E string effectively. I can improve with more work but is there anything else I can do or possibly substitute with to be more effective? I would have surgery in a second but the bones in my elbow are fused. I want to be a great bass player and I see great piano players that are blind and hate to use a little thing like this as an excuse. Any tricks or suggestions will be greatly appreciated.