Secondary thalamic injury: A link between acute injury and long-term sequelae of TBI?

Abstract

Traumatic brain injury (TBI) is common,1 and survivors of moderate and severe TBI often have long-term injury-related disabilities, which prevent or interfere with their ability to support themselves and even to maintain independence in activities of daily life.2,3 The chronic disability-related consequences of traumatic brain injuries are well documented and substantial. One study by Selassie et al.2 estimated that 43.3% of civilians hospitalized with TBI in the United States in 2003 would have long-term disability related to impairment in activities of daily living, postinjury symptoms, and cognitive impairment at 12 months after discharge. Similarly, a recent study on military patients treated in hospitals, emergency departments, and theater level 3 to 5 military treatment facilities predicted that 65.6% of treated service members with severe TBI, 56.2% with penetrating TBI, 31.4% with moderate TBI, and 12.0% with mild TBI would develop long-term disability.4 Although TBI is widely recognized as an acute injury that often leads to long-term impairment, recovery and return to productive activity do occur within each injury severity category, albeit less frequently for the severely injured. One of the challenges for the TBI research and clinical communities is determining which preinjury and secondary injury conditions are mechanistically associated with outcomes after TBI. Such evidence-based determinations would inform future efforts tailored to improving outcomes for specific TBI survivor groups.