The current state of biomarkers of mild traumatic brain injury.

Mild traumatic brain injury (mTBI) is a common occurrence, with over 3 million cases reported every year in the United States. While research into the underlying pathophysiology is ongoing, there is an urgent need for better clinical guidelines that allow more consistent diagnosis of mTBI and ensure safe return-to-play timelines for athletes, nonathletes, and military personnel. The development of a suite of biomarkers that indicate the pathogenicity of mTBI could lead to clinically useful tools for establishing both diagnosis and prognosis. Here, we review the current evidence for mTBI biomarkers derived from investigations of the multifactorial pathology of mTBI. While the current literature lacks the scope and size for clarification of these biomarkers' clinical utility, early studies have identified some promising candidates.