During a run-out attempt, removing the bails using the hands holding the ball is a valid run-out.
But when a fielder removes the bails or stumps using his elbow or shoulder, is it still a valid dismissal?
Yes, this is explicitly allowed by the Laws of Cricket; quoting from Law 29 "The Wicket is Down":
29.1.1 The wicket is put down if a bail is completely removed from the top of the stumps, or a stump is struck out of the ground,
22.214.171.124 by a fielder with his/her hand or arm, providing that the ball is held in the hand or hands so used, or in the hand of the arm so used.