On the relationships between applied force, photography technique, and the quantification of bruise appearance

Black, Heather I. and Coupaud, Sylvie and Nic Daiéd, Niamh and Riches, Philip E. (2019) On the relationships between applied force, photography technique, and the quantification of bruise appearance. Forensic Science International, 305. ISSN 0379-0738 (https://doi.org/10.1016/j.forsciint.2019.109998)

[thumbnail of Black-etal-FSI-2019-applied-force-photography-technique-and-the-quantification-of-bruise-appearance]
Preview
Text. Filename: Black_etal_FSI_2019_applied_force_photography_technique_and_the_quantification_of_bruise_appearance.pdf
Accepted Author Manuscript
License: Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 logo

Download (768kB)| Preview

Abstract

Bruising is an injury commonly observed within suspect cases of assault or abuse, yet how a blunt impact initiates bruising and influences its severity is not fully understood. Furthermore, the standard method of documenting a bruise with colour photography is known to have limitations which influence the already subjective analysis of a bruise. This research investigated bruising using a standardised blunt impact, delivered to 18 volunteers. The resulting bruise was imaged using colour, cross polarised (CP) and infrared photography. Timelines of the L*a*b* colour space were determined from both colour and CP images for up to 3 weeks. Overall, no single photographic technique out-performed the others, however CP did provide greater contrast than colour photography. L*a*b* colour space timelines were not attributable any physiological characteristics. Whilst impact force negatively correlated with BMI (R2 = 0.321), neither were associated with any measure of bruise appearance. Due to the inter-subject variability in the bruise response to a controlled infliction, none of the methods in the current study could be used to reliably predict the age of a bruise or the severity of force used in creating a bruise. A more comprehensive approach combining impact characteristics, tissue mechanics, enhanced localised physiological measures and improvements in quantifying bruise appearance is likely to be essential in removing subjectivity from their interpretation.