Is fingerprint ridge density influenced by hand dimensions?

BACKGROUND AND OBJECTIVE: Various aspects of fingerprint resarch were extensively explored in the past. However, the correlation between fingerprint ridge density and hand dimensions has not yet been documented. Therefore, the present study has investigated the relationship so that some conclusions regarding the association can be established. METHODS: The study included 500 subjects (250 males and 250 females) between the ages of 18 to 25 years who belonged to the Rajput community of the Shimla and Solan districts of Himachal Pradesh state of North India. The sexual dimorphism among the ridge count was examined using student's t-test. The relationship of fingerprint ridge density with hand dimensions among both the sexes and pooled data was analyzed using Pearson's correlation coefficient. RESULTS: All the fingers on both hands showed statistically significant sex differences. When all digits were considered together, the left little finger in males and right middle finger in females showed a weak but significant correlation with hand length while all the digits when considered in combination reported strong correlation hand length measurements. Similarly, right thumb showed significant correlation with hand breadth. All the ten digits showed highly significant correlation with hand breadth when pooled data was examined. CONCLUSION: The ridge density correlates with the hand dimensions in the case of pooled data. This relationship can then be used to devise prediction equations for hand dimensions based on ridge density, or vice-versa for pooled data. The equations will also help in estimating hand dimensions based on ridge density and vice-versa.

Sex estimation from fingerprint ridge density. A review of literature.

Identification has always been very vital in forensic casework. Fingerprint patterns are population-specific and individualistic, that makes fingerprinting an important biological trait in human biology and forensics. Fingerprint is an impression of the friction ridges of the finger-ball, where friction ridges are raised portions of the epidermis. Skin on human fingertips contains ridges and valleys which together forms distinctive patterns. These patterns are fully developed in intra-uterine life and remain unaltered until the death of the individual. Injuries such as cuts, burns and bruises can temporarily damage quality of fingerprints but when fully healed, the patterns are restored. The number of ridges present in a unit area on a fingerprint is called the Fingerprint Ridge Density (FPRD). The epidermal ridge density can be determined by examining two parameters - ridge width and distance between the ridges. The thickness of the epidermal ridges varies between individuals and between the sexes. The present review of literature focuses on the sexual dimorphism on the basis of the FPRD and its possible use in forensic examinations. Most of the studies pertaining to the estimation of sex from the FPRD have been conducted in the last two decades when Mark A. Acree in 1999, devised a method of estimation of sex on Caucasian and African-American descent. The present analysis evaluates the studies found in the PubMed database conducted after Acree, 1999. The estimation of sex from the FPRD is based upon the fact that the females have a fine detailing of ridges and consequently more ridges are covered in a unit space in the fingerprints of females as compared to males. The paper also highlights -recent advancements and future perspectives in the area of FPRD. (www.actabiomedica.it).