Greater Occipital Nerve Injection Study

GON will be identified at the novel, proximal C2 location on the symptomatic side via ultrasound guidance. Prior to injection, an independent examiner will perform a sensory exam of the involved dermatome. A 25 gauge spinal needle will be inserted into the symptomatic side after locating the GON via ultrasound at the C2 level. Subjects will be injected with treatment medication. Thirty minutes after injection, an independent examiner will test for anesthesia over the desired dermatome. VAS will be assessed pre-injection, 30 post-injection, 2 weeks post-injection and 1 month post-injection. The 2 week and 1 month assessments will be conducted by telephone.