Postconcussive syndrome is roughly defined as the persistence of symptoms after a concussion. Headaches, dizziness, fatigue, emotional instability, anxiety, sleep disturbances and an overall decreased quality of life are described as the most important complaints. A comprehensive diagnostic and therapeutic approach, primarily based on the ability to conduct a complete physical workup, is necessary in order to prevent long-term impairment.
Traumatic brain injury (TBI) might lead to severely debilitating long-term sequelae in the absence of an early diagnosis and adequate treatment, one of the most important forms being a concussion, defined as a traumatic event during which various pathophysiological processes (primarily mechanical forces exerted on brain tissue) lead to brain injury, but without evidence on imaging studies [1]. Various symptoms appear shortly after the initial injury, including headaches, amnesia, and loss of consciousness, whereas emotional instability, sleep disturbances, and cognitive impairment (reduced reaction time is a key finding) can be present as well [1]. Postconcussive syndrome (PCS) is still an incompletely defined disorder that several authors describe as prolongation of symptoms after a concussion [2] [3]. The majority of patients recover from a concussion within a period of days to weeks, but PCS is estimated to occur in approximately 10% of cases [4]. Notable findings in PCS include persistent emotional instability, difficulty sleeping, anxiety, dizziness, irritability, visual disturbances, sensitivity to noise, and inability to maintain concentration, in addition to complaints mentioned previously [2] [3] [5] [6]. Depression may also be a long-term adverse effect of concussion and is an important constituent of PCS [1] [7].
Physicians must bear in mind the importance of an early diagnosis of concussion and proper initiation of therapy, particularly in younger athletes. For this reason, a meticulous clinical workup is recommended. Firstly, a detailed patient history must cover all the details regarding the event that led to brain injury (time, description of the mechanism of injury, and severity of impact) and evaluate the presence of associated symptoms [1]. The Sport Concussion Assessment Tool 2 (SCAT2), comprising of a series of self-evaluating questions, a Glasgow coma scale grading (GCS), cognitive assessment, as well as examination of balance and coordination, is a comprehensive tool that can be of significant benefit in assessing individuals in whom a concussion is suspected [1]. The subjective nature of this test, however, is a major limitation [2]. In addition to findings obtained during the interview with the patient, a complete physical and neurological examination is also important. Clinical criteria should be supported by various tests, the most important being the treadmill test that determines whether symptoms appear or become exacerbated with exercise [2] [8]. If patients are unable to perform strenuous activities after TBI due to the reappearance of symptoms, the diagnosis of PCS is highly likely [2] [8]. The role of imaging studies in identifying additional injuries to other structures (eg. the cranium) is quite important but is of little benefit for PCS due to the absence of macroscopic changes in the brain after a concussion.