Abnormal neurological exam findings in individuals with mild traumatic brain injury (mTBI) versus psychiatric and healthy controls.

In those with a history of mild traumatic brain injury (mTBI), cognitive and emotional disturbances are often misattributed to that preexisting injury. However, causal determinations of current symptoms cannot be conclusively determined because symptoms are often nonspecific to etiology and offer virtually no differential diagnostic value in postacute or chronic phases. This population-based study examined whether the presence of abnormalities during neurological examination would distinguish between mTBI (in the chronic phase), healthy controls, and selected psychiatric conditions. Retrospective analysis of data from 4462 community-dwelling Army veterans was conducted. Diagnostically unique groups were compared on examination of cranial nerve function and other neurological signs. Results demonstrated that individuals with mTBI were no more likely than those with a major depressive disorder, generalized anxiety disorder, posttraumatic stress disorder, or somatoform disorder to show any abnormality. Thus, like self-reported cognitive and emotional symptoms, the presence of cranial nerve or other neurological abnormalities offers no differential diagnostic value. Clinical implications and study limitations are presented.