The patient was a 64-year-old woman who reported a sudden onset of neck pain and headaches following a fall 2.5 months prior to her initial physical therapy visit. Cervical spine radiographs, which were ordered by the referring physician, revealed extensive degenerative disc disease of the lower cervical spine. At her initial physical therapy evaluation, cervical spine range of motion was within functional limits except for bilateral rotation, which was limited to 45 degrees due to pain and stiffness. The patient's headache symptoms were abolished with the Sharp-Purser test. Although assessment of symptoms was not the intent of the Sharp-Purser test, a reduction of symptoms during the test would warrant further evaluation. Therefore, the physical therapist ordered cervical spine flexion-extension radiographic views to assess for atlantoaxial instability. The radiologist's report noted a stable atlantodens interval that did not change with cervical flexion and extension and a course of physical therapy was initiated. At the time of discharge from physical therapy, the patient reported no neck pain and only very mild occasional headaches, which she believed she could manage on her own.