Morbidity Related to Age at Time of Injury

Since children have a better rate of survival after TBI, it is often assumed that pediatric outcomes are more favorable than adult outcomes. This is often attributed to the plasticity theory, suggesting that the young brain has a better opportunity to recover function.

TBI during infancy has been shown to result in difficulty developing expressive and receptive lan­guage skills. Infants sustain a higher proportion of TBI that are secondary to nonaccidental trauma and their outcomes are poor. Koskiniemi (258) reported the long-term outcome of TBI in children and identified that the worst outcomes typically occurred in those children who were younger than 4 years of age. That study demonstrated similar results to a study done by Kriel (62) in which 97 pediatric patients who were unconscious for greater than 24 hours were followed, with the worst outcomes seen in children who were younger than 6 years of age and involved both cogni­tive and motor impairment.

Older children show fairly good recovery of lan­guage function and independent ambulation. This was evaluated in a study of 28 adolescents followed longitudinally after brain injury. Twenty-five of them recovered language function, and 21 of them recov­ered independent ambulation. However, they had a lower high school graduation rate and employment rate than an age-referenced population. Their social interactions are impaired, as two-thirds of these indi­viduals reported that after their TBI, their social life declined, and in fact, only 1 of the 28 subjects was married at the time of the follow-up, compared with 61% of the reference population (61).