A system for correcting the position of bones, bone parts or vertebrae is provided, comprising a first bone anchor (10) including a shank (2) for anchoring in bone and a receiver (5) for receiving a rod (6) and for connecting the rod (6) to the shank (2), a second bone anchor (10') including a shank (2) for anchoring in bone and a receiver (5) for receiving a rod (6) and for connecting the rod (6) to the shank (2), a positioning member (30) having a longitudinal axis (1), a first coupling member (40) for coupling the positioning member (30) to the first bone anchor (10), a second coupling member (40') for coupling the positioning member (30) to the second bone anchor (10'), wherein the second coupling member (40') is movable relative to the first coupling member (40') on the positioning member (30) along the longitudinal axis (1).
