Phase I of the study (motion and quality assurance [QA] study) is being used to determine intrafraction target motion and define quality assurance procedures for single fraction spinal radiosurgery. The Phase II portion of the study is being used to estimate the palliative response (pain or relief of neurologic symptoms) and local control for single fraction radiosurgery delivered with TomoTherapy and to assess the acute and late toxicity of spinal radiosurgery.