Postconcussion syndrome.

Postconcussion syndrome (PCS) is a heterogeneous condition comprised of a set of signs and symptoms in somatic, cognitive, and emotional domains. PCS is a controversial concept because of differing consensus criteria, variability in presentation, and lack of specificity to concussion. Whereas symptoms of concussion resolve in most individuals over days to weeks, a minority of individuals experience symptoms persisting months to years. The clinical consequences of concussion may be best conceptualized as two multidimensional disorders: (1) a constellation of acute symptoms termed early-phase posttraumatic disorder (commonly headache, dizziness, imbalance, fatigue, sleep disruption, impaired cognition, photo- and phonophobia); and (2) late-phase posttraumatic disorder, consisting of somatic, emotional, and cognitive symptoms. This phase is highly influenced by various psychosocial factors and is much less specific to the brain injury itself. Risk factors for development of a late-phase disorder include a high early symptom burden (e.g., headache, fatigue), a history of multiple concussions, psychiatric conditions (anxiety, depression), longer duration of unconsciousness or amnesia, and younger age. Successful treatment requires thoughtful differential diagnosis, including consideration of comorbid and premorbid conditions and other possible contributing factors. Treatment should include a hierarchic, sequential approach to management of treatable symptoms that impact functioning, such as depression, anxiety, insomnia, headache, musculoskeletal pain, and vertigo. A guided prescription of aerobic exercise is beneficial for early- and late-phase disorders after concussion.