BACKGROUND: Prior studies identified that crash severity (delta V), occupant position, and restraint systems as reliable predictors of crash injuries to lower extremity, but very little have been written on the subject of upper extremity. METHOD: This is a retrospective analysis of Crash Injury Research and Engineering Network database in a Level I trauma center focusing on severe upper extremity injuries. The aim was to investigate the relationship between types of the "crash" and "occupant" factors on the pattern and severity of upper extremity injuries after a frontal collision. RESULTS: Majority of the injuries were soft tissues nature (67.6% soft tissue vs. 32.4% fractures). There were 144 fractures to the upper extremity, 12.5% were "open" fractures; 74.5% of the fractures sustained in the upper extremity occurred distal to the elbow, whereas soft tissue injuries predominated in the humerus. Also noted that occupants who sustained fractures were on average 6.7 kg lighter than those who sustained soft tissue injuries (84.5 kg soft tissue vs. 77.86 kg fracture, p < 0.05). We postulate that there may be a protective effect of "soft tissue cushion" toward protecting the content from serious harm, in this case the humerus. Instrument panel, airbag, and seat belts were the main injury source. After adjusting for other modifiers, occupants who sustained fractures had a significantly higher Injury Severity Scores (mean Injury Severity Scores 21.88 vs. 17.68, p < 0.05). This implied that those who sustained fractures to upper extremity most likely had associated significant injuries to other body region, necessitating further medical attention. CONCLUSION: Further improvement in vehicle safety performance in the form of "depowered" airbag and efficient energy absorbing material within the vehicle interior is warranted.
BACKGROUND: Prior studies identified that crash severity (delta V), occupant position, and restraint systems as reliable predictors of crash injuries to lower extremity, but very little have been written on the subject of upper extremity. METHOD: This is a retrospective analysis of Crash Injury Research and Engineering Network database in a Level I trauma center focusing on severe upper extremity injuries. The aim was to investigate the relationship between types of the "crash" and "occupant" factors on the pattern and severity of upper extremity injuries after a frontal collision. RESULTS: Majority of the injuries were soft tissues nature (67.6% soft tissue vs. 32.4% fractures). There were 144 fractures to the upper extremity, 12.5% were "open" fractures; 74.5% of the fractures sustained in the upper extremity occurred distal to the elbow, whereas soft tissue injuries predominated in the humerus. Also noted that occupants who sustained fractures were on average 6.7 kg lighter than those who sustained soft tissue injuries (84.5 kg soft tissue vs. 77.86 kg fracture, p < 0.05). We postulate that there may be a protective effect of "soft tissue cushion" toward protecting the content from serious harm, in this case the humerus. Instrument panel, airbag, and seat belts were the main injury source. After adjusting for other modifiers, occupants who sustained fractures had a significantly higher Injury Severity Scores (mean Injury Severity Scores 21.88 vs. 17.68, p < 0.05). This implied that those who sustained fractures to upper extremity most likely had associated significant injuries to other body region, necessitating further medical attention. CONCLUSION: Further improvement in vehicle safety performance in the form of "depowered" airbag and efficient energy absorbing material within the vehicle interior is warranted.