“…9 The differential diagnosis of PCS includes depression, somatization, chronic fatigue, chronic pain, cervical injury, vestibular dysfunction, ocular dysfunction, or some combination of these conditions. 15 The challenge for clinicians is to determine whether prolonged symptoms after concussion reflect a prolonged version of the concussion pathophysiology versus a manifestation of a secondary process such as premorbid clinical depression, a cervical injury, or migraine headaches. 16,17 It is therefore essential that the clinician obtain a history of prior affective or medical problems, perform a careful physical examination, and consider the response to exertion (ie, whether exertion reliably exacerbates symptoms) 18 when developing the differential diagnosis of persistent post-concussion symptoms.…”