Objective: To identify differences in outcome after traumatic brain injury (TBI) compared with orthopedic injuries as a function of age.

Design: Longitudinal data analyses from an inception cohort.

Setting: Outpatient rehabilitation program.

Participants: Eighty-two orthopedic injury patients and 195 TBI patients.

Interventions: Not applicable.

Main outcome measures: Independent living, employment, and level of functioning 1 to 2 years after injury.

Results: Older patients and those with TBI were more likely to have increased dependence postinjury. Older TBI patients were more likely to have changes in employment status compared with orthopedic injury patients younger or TBI. The Mayo-Portland Adaptability Inventory and Disability Rating Scale were moderately predictive of level of functioning, return to employment, and independent living status 1 to 2 years postinjury. Injury severity was only mildly predictive of outcome.

Conclusions: The effect of age on outcome affects recovery from neurologic injuries and, to a lesser extent, orthopedic injuries. Outcome after TBI is best predicted by patients' age and estimates of level of function at discharge. Findings suggest that older patients and those with TBI have a greater likelihood of becoming physically and financially dependent on others. Rehabilitation efforts should focus on maximizing levels of independence to limit financial and emotional costs to patients and their families.