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Fight Bite Injuries: Aggressive Tendencies Associated with Smaller Second to Fourth Digit Ratio.
Cormac W Joyce1, Andrew O' Regan1, Jack L Kelly2
1* Department of Plastic, Reconstructive and Hand Surgery, Cork, Ireland.
The Journal of Hand Surgery Asian-Pacific Volume
|November 10, 2017
Summary
Men with fight bite injuries have a lower second to fourth digit ratio (2D:4D), indicating higher prenatal androgen exposure and a potential predisposition to aggression. This finding suggests a link between prenatal hormones and adult aggressive behavior.
Area of Science:
- Andrology
- Human Biology
- Forensic Medicine
Background:
- Fight bite injuries are commonly sustained by young males during aggressive altercations.
- The second to fourth digit ratio (2D:4D) is a marker of prenatal androgen exposure.
- Lower 2D:4D ratios are associated with traits such as aggression.
Purpose of the Study:
- To investigate the 2D:4D ratios in individuals with fight bite injuries.
- To compare these ratios with an age and gender-matched control group.
Main Methods:
- Hand radiographs from 133 fight bite patients and 133 controls were analyzed.
- The 2D:4D ratio was calculated for each individual.
- Statistical analysis compared ratios between groups.
Main Results:
- Male fight bite patients exhibited significantly lower 2D:4D ratios compared to the male control group (p < 0.05).
- No significant difference in 2D:4D ratios was found between female fight bite patients and the female control group (p > 0.05).
Conclusions:
- The findings suggest that a lower 2D:4D ratio in males is associated with sustaining fight bite injuries.
- This supports the hypothesis that prenatal androgen exposure influences adult aggressive tendencies.
- A lower 2D:4D ratio may serve as a potential predictor for aggressive behavior and associated injuries.
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