Try this......turn IK off on right arm. Then zero the collar, shoulder, forearm and hand parameters for the right side. Then reposition the arm by sections starting with the right collar. Use small settings evenly on each body part until the arm is where you want it. This should fix the breaking problem. What's happening is you have one body part's parameters set too extreme and the others aren't set at all or very little. Remember that when you move your arm in real life that your collar, shoulder, forearm, and hand each move in conjunction.......good luck...... Krel