A clamp for attaching a cross connecting device to a spinal fixation system comprising an outer body and an inner body. The outer body defines an internally threaded bore and an outer body cavity, and the inner body defines an inner body cavity. The inner body is at least partially disposed within the outer body. A pin is provided for connecting the inner and outer bodies to each other, while allowing for a limited amount of movement therebetween. A set screw suitable for being driven into the internally threaded bore is provided for securing the inner body to the spinal fixation system.
