Axis Slant and Rotation of the Central Ridge for Hand Determination (Right - Left) in Plain Spiral Whorl Single-digit Fingerprint Pattern Obtained from a Sample of Egyptians

Background: Fingerprints are the commonest identification tool used for forensic investigation. Identification of the sidedness of the suspect's hand (left or right) is a crucial step for the accurate detection of the suspect by reducing the investigator's effort and time of analysis. Aim of the work: This study aimed to evaluate the usefulness of axis slant and rotation of the central ridge to determine whether a single-digit plain spiral whorl print is from a right or left hand in a sample of Egyptians. Subjects and Methods: The ten-digit rolled fingerprints were obtained from 128 adult healthy Egyptian participants residing in the Middle Delta region. Out of the 1280 collected prints, 186 plain spiral whorls, including 93 right and 93 left-handed prints, were included and submitted for analysis using (CorelDRAW 2021). Major dermatological injuries or chemotherapy that affects fingerprints were excluded. Axis slant, either right, left, or absent, and rotation of the central ridge, either clockwise or anti-clockwise, were used for the analysis. Chi-square test, Monte Carlo correction, and multivariable binary regression were applied. Results: There was a significant association between the hand side and the direction of the axis slant and the rotation of the central ridge. Right axis slant and anticlockwise rotation could suggest the right-handedness of the print. However, left hand print could be suggested from left axis slant and clockwise rotation.Conclusions: The axis slant and rotation of the central ridge could be applied to determine whether a single-digit plain spiral whorl pattern print is from a right or left hand.