A medical instrument impacting tool that is useful for mating to a medical instrument used during spinal surgery is provided. The impacting tool is effective to apply a force to the medical instrument to efficiently and effectively prepare a bone structure, insert or remove a trial implant, insert or remove an implant, or to remove a medical instrument positioned between adjacent bone structures. In general, the medical instrument impacting tool includes a hollow tube, a handle slidably disposed around the tube, and a mass connected to the handle and slidably disposed within the tube.