In my last forensic update, I offered an overview of what we know scientifically about patients with persistent Post Concussive Disorder. On June 2, 2019, the Journal of the American Medical Association Neurology (doi:10.1001\jamaneurol.2019.1313) published an important new body of research examining the persistence of post concussive symptoms as well as recovery in individuals with mild traumatic brain injury presenting to U.S. level one trauma centers. To this date, the available research, much of which I reviewed in my previous forensic update, has suggested that the majority of individuals experiencing a mild traumatic brain injury, sometimes up to 90%, experience or at least report full recovery within one to two years. These data often form our foundation in discussing this issue with patients in clinical settings. These data are often used in forensic settings to raise questions as to the possible additional or contributing etiologies to individuals presenting with persistent post concussive symptoms long after a mild TBI.
It is important to note that most traumatic brain injuries are classified as mild based on admission Glasgow Coma Scale scores of 13 to 15 (15 is a full score indicating no measured deficits). The true prevalence of persistent functional limitations for these individuals continues to be debated. These authors are part of a group evaluating traumatic brain injury longitudinally in a series of studies under the umbrella of transforming research and clinical knowledge of traumatic brain injury (TRACK-TBI). This cohort study of patients with mild TBI presenting to U.S. level one trauma centers enrolled patients over a four year period and followed them for up to twelve months. Nearly 1,500 patients in eleven different level one trauma emergency departments or inpatient units were included in this study. These individuals were enrolled within twenty-four hours of injury. They had admission Glasgow Coma Scores of 13 to 15.
Most participants in the mild TBI group (87%) reported functional limitations at two weeks post-injury. At twelve months, the percentage of participants reporting functional limitations was 53%. A higher percentage of patients with positive computerized tomography (CT) findings reported impairment (61%) compared to those without CT findings (49%).
This multi-site study led authors to conclude that many patients with mild traumatic brain injury presenting to U.S. level one trauma centers report persistent injury-related life difficulties at one year post-injury. This suggests the need for more systematic follow-up of patients with mild TBI to provide treatment and reduce the risk of chronic problems. This data has significant implications for our forensic work. If these data are replicated, they provide a new understanding for patients, particularly in forensic settings, reporting chronic post-concussive symptoms at twelve months or more post injury. It is likely that for some of these individuals, problems with chronic pain or mental health challenges also contribute to a continuation or exacerbation of concussive symptoms. Regardless, the implication for forensic evaluators is clear – when individuals experiencing a mild traumatic brain injury report chronic symptoms for twelve months or more - they may not be in the minority as has been suggested in the past but actually represent a significant percentage of recovering individuals.
