Double Trouble - The prevalence of concomitant traumatic brain injury in patients with spinal cord injury and its impact on functional outcomes: a systematic review

This systematic review examines the prevalence, diagnostic challenges, and functional impact of concomitant traumatic brain injury (TBI) in patients with traumatic spinal cord injury (SCI). PubMed, Embase, Scopus, and PsycINFO databases were searched with a search strategy containing key search terms for TBI, SCI and concomitant. Original research articles reporting on prevalence and/or functional outcomes following a TBI at the time of SCI in adult populations were included. Forty studies met the inclusion criteria, with 32 providing a prevalence estimate of the incidence and 18 information on functional outcomes. Reported prevalence rates of concomitant TBI varied widely (30–50%) across studies, largely due to inconsistent diagnostic criteria, retrospective data collection, and reliance on incomplete medical records or ICD coding. The identification of mild TBI (mTBI) is particularly problematic, given the lack of definitive diagnostic criteria. Motor vehicle accidents were the most common mechanism of concomitant injury, accounting for ∼80% of moderate–severe TBI cases, but TBI occurrence was not consistently associated with a specific SCI level. Moderate–severe TBI significantly increased in hospital mortality and complications like pneumonia, sepsis, but had minimal effects on rehabilitation trajectory or length of stay once patients with very low initial GCS were excluded. Functional outcomes, particularly motor and sensory recovery, were generally unaffected by concomitant injury, though subtle cognitive deficits were observed in moderate to severe TBI cases during rehabilitation. Few studies examined outcomes beyond one year post injury. Overall, current evidence suggests that concomitant TBI is common in SCI patients, but its long term functional and cognitive impact remains underexplored. Future research should employ standardized diagnostic criteria, prospective data collection, and long term follow up to clarify the role of concomitant TBI in SCI recovery and guide targeted rehabilitation strategies.