Title: The impact of axial injury, extra-axial injury, and combined injury on functional status in traumatic brain injury (tbi) Authors

Title: The impact of axial injury, extra-axial injury, and combined injury on functional status in traumatic brain injury (TBI)

Authors: Nhung Quach M.D., Reza Ehsanian M.D. Ph.D., Samantha Sechrist, Saranya P. Balakrishnan M.D. Thao Duong M.D., James Crew M.D., & Linda Isaac PhD.

Objectives:

1. 
   Describe functional status by using the disability rating scales (DRS) and functional independence measure (FIM) scores in axial lesions, extra-axial lesions and combined lesion groups
   
2. 
   Investigate the affecting differences between three types of injury in functional status.
   

Design: Prospective longitudinal study. Head computed tomography (CT) scans were taken within 7 days from date of injury were evaluated. The population was divided into three groups based on the radiographic presentation of the lesions: extra-axial (epidural hematoma, sub-epidural hematoma, and subarachnoid hemorrhage), axial (punctate/petechial hemorrhages, intra-ventricular hemorrhage, cortical parenchymal lesions, non-cortical parenchymal lesions), and combined (involving both axial and extra-axial lesions). DRS and FIM was used to evaluate function at 3 time points (admission, discharge, and one-year follow-up).
Setting: Patients from the Northern California Traumatic Brain Injury Model System of Care (TBIMS) were admitted to the rehabilitation department between 1989-2011 and followed up to 1 year post injury.

Participants: There were 450 moderate to severe TBI patients. Patients lost to follow-up, without head CT scan results, or without intracranial lesions were excluded from the study.

Interventions: None

Main Outcome Measures: head CT, DRS, and FIM

Level of Evidence: 2b

Results: No statistical differences were found in functional status between the axial and extra-axial groups, except for the FIM follow-up after 1 year, which unexpectedly showed the axial group having greater functional recovery (p=.046). The combined lesion group showed statistically significant greater negative impact on functional status than the other groups across all three time points.

Conclusions:

Combined lesions negatively affect functional status more than axial lesions or extra-axial lesions. The effect of combined injuries will increase the awareness of healthcare providers and likely inform the patient care and patient likelihood of recovery.