TAKE-HOME POINTS
Mild traumatic brain injury (mTBI), a term synonymous with concussion, is an acute, complex pathophysiologic process that is induced via traumatic biomechanical forces.
mTBI resolves rapidly over days to weeks with no significant long-term sequelae. However, some patients who sustain mTBI experience postconcussive syndrome (PCS) for years after the original injury.
Initial management is complete rest, without cognitive or physical activity, for at least 1 day. Patients may progress to light activities if they are symptom-free. A symptom-free status is required at each subsequent step in recovery.
WHO SHOULD READ THIS?
This material is relevant to physician assistants who provide care to patients with new diagnosis or a history of mild traumatic brain injury (mTBI). Physician assistants who practice in emergency medicine, urgent care, and sports medicine should be aware of how to diagnose and manage the care of patients with traumatic brain injuries.
WHY IS THIS IMPORTANT?
At least 1.5 million new cases of traumatic brain injury (TBI) occur in the United States each year;1-5 approximately 80% of these injuries are identified
as mTBI, a term synonymous with concussion. Mild traumatic brain injury is an acute, complex pathophysiologic process that is induced via traumatic biomechanical forces.1,6 Most mTBIs occur as a result of motor vehicle collisions, falls, or sports injuries. Traditionally, children are at highest risk for mTBI because of its correlation with sports participation.1,5 However, approximately 179,000 cases of traumatic brain injury have been officially diagnosed in military service personnel since 2000,7 with approximately 76% of those injuries diagnosed as mTBI. In addition, approximately 16% of soldiers deployed to Iraq and Afghanistan self-reported events consistent with mTBI.8-10
Concussions and mild traumatic brain injury may be associated with chronic neurologic axis sequelae. Signs and symptoms may persist for many years after the original injury.2Table: Variability in criteria for diagnosis of mTBI (in the online version of this article) summarizes the diagnostic criteria used for mTBI.
In most patients, mTBI resolves rapidly over days to weeks with no significant long-term sequelae. However, some patients who sustain mTBI experience postconcussive syndrome (PCS) for years after the original injury. Postconcussive syndrome includes the persistence of initial findings or the development of new symptoms, such as depression, anxiety, personality changes (aggressive behaviors), and insomnia. The specific diagnostic criteria for PCS are ambiguous and confounded by symptoms indirectly accessible to objective assessment.
The International Classification of Diseases, 10th Edition (ICD-10) and the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition, Text Revision (DSM-IV-TR) require a history of mTBI and at least three of eight additional criteria for a diagnosis11,12 (Table: Diagnostic criteria for postconcussive syndrome in the online version of this article). The most common PCS symptoms include headache, dizziness, and fatigue. Among civilian populations, 20% to 90% of those who sustain mTBI may experience PCS.2,3,5,13 After 1 year, at least one symptom of PCS persists in 8% to 25% of patients with mTBI. Preexisting medical and psychological states and prior and subsequent psychosocial dynamics are comorbidities. Psychological stress from the event itself may contribute to observed symptoms.3,5,13
Incidence rates for PCS among military combatants remain elusive. Symptoms of postconcussive syndrome overlap with those of posttraumatic stress disorder (PTSD), and exposure to concussive events is common in training and combat.8,10,14 Additional influencing factors include the stigma associated with mental illness and competing neurologic and psychological symptoms that can make determining appropriate management challenging.3,8-10,13,14