Post-concussion syndrome
Post-concussion syndrome, also known as postconcussive syndrome or PCS, is a set of symptoms that may continue for weeks, months, or a year or more after a concussion – a mild form of traumatic brain injury (TBI). The rates of PCS vary, but most studies report that about 15% of individuals with a history of a single concussion develop persistent symptoms associated with the injury. A diagnosis may be made when symptoms resulting from concussion last for more than three months after the injury. Loss of consciousness is not required for a diagnosis of concussion or post-concussion syndrome.
Concussion
Definitions of mild traumatic brain injury (MTBI) were inconsistent until the World Health Organization's International Statistical Classification of Diseases and Related Health Problems (ICD-10) provided a consistent, authoritative definition across specialties in 1992.
Since then, various organizations such as the American Congress of Rehabilitation Medicine and the American Psychiatric Association in its "Diagnostic and Statistical Manual of Mental Disorders" have defined MTBI using some combination of loss of consciousness (LOC), post-traumatic amnesia (PTA), and the Glasgow Coma Scale (GCS).