STATURE ESTIMATE USING FOOT AND FOOTPRINTS DIMENSIONS

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1 STATURE ESTIMATE USING FOOT AND FOOTPRINTS DIMENSIONS Petra Uhrová 1, Radoslav Beňuš 1, Soňa Masnicová 2 1 Department of Anthropology, Faculty of Natural Sciences, Comenius University in Bratislava, Mlynská dolina, Bratislava, Slovakia 2 Department of Criminalistics and Forensic Sciences, Academy of Police Force, Sklabinská 1, Bratislava, Slovakia Corresponding author: uhrova@fns.uniba.sk Abstract The foot measurements are important in forensic field as they can be used as body height predictors for an individual. The aim of the study was to find the relation between stature and foot measurements and to generate population-specific equations. We measured the stature and bilateral foot and footprint measurements (foot and footprint length, foot and footprint breadth, malleol and navicular height) of 85 volunteers (49 females and 36 males students) ranging in age between 18 and 30 years using standard measurements technique. The obtained values were statistically analyzed using SPSS 17.0 for Windows. The results revealed non-significant bilateral differences in males and females (p<0.05). Sex differences were found to be significant in all foot and footprint measurements (p<0.001). The highest significant and positive correlation coefficients with stature were observed for foot length in males (r=0.716) and in females (r=0.728).according to the non-significant sex effects on the relationship between stature and foot dimensions, the regression equations were computed only for the pooled mixed-sex group. Our study provides equations that can help to estimate stature from foot measurements among Slovaks. Key words: forensic anthropology, stature estimation, footprint measurements, foot length, foot breadth. 1 Introduction Estimation of individual s stature is an important parameter in forensic field. The anthropometry and anatomy of the foot has been examined for many years. It has been established previously that the dimensions of the lower extremity show greater association with the body height than those of the upper extremity (Özaslan et al., 2003; Fessler et al., 2005). Examination of footprints can help in estimation of stature of an individual. The present study has been conducted to find the relation between stature and various foot and footprint dimensions such as foot and footprint length, foot and footprint breadth, malleol and navicular height of foot. The morphology of human foot shows the variations due to the combined effects of heredity, lifestyle and climatic factors (Krishan, 2007a; Robbins, 1978). Therefore, population-specific equations for stature estimation based on foot dimensions and footprints are presented for Slovak population. 2 Material and Methods The research was carried out in the Department of Anthropology, Faculty of Natural Sciences, Comenius University, Slovakia. Stature, right and left foot and footprints measurements (foot length, foot breadth, foot malleol height, foot naviculare height, footprint length and footprint breadth) were obtained from 49 female and 36 male students aged between 18 and 30 years. These were common college students with normal gait and motion activity. Subjects with foot deformities or those who underwent a foot operation were excluded from the study. Measurements were recorded during period between April 2009 and November 2011 on barefoot subjects. Because of the diurnal variation in stature, all subjects were measured approximately at the same time in the morning. 94

2 Stature (S) was measured with an anthropometer and was taken from the vertex to the floor with the person standing barefoot in the anatomic position and with the head in Frankfurt Plane (Martin, Saller, 1957). Foot length (FL) was measured as the direct distance from the most posterior point of the heel (pternion) to the most anterior point of the longest toe - first or second (acropodion) (Martin et al., 1957). Foot breadth (FB) is defined as the distance between the surfaces of the first and fifth metatarsal bone heads (Martin et al., 1957). Footprint length (FpL) and breadth (FpB) were measured like the foot measurements, according to procedure of Robbins (1986). The foot medial malleol height (FMH) is a distance between the lower bound of tibial malleols to the floor. The foot navicular height (FNH) is a distance between the most superior projecting part of the navicular bone and the floor, the dorsal side of foot. 2.1 Statistical analysis The obtained values were statistically analyzed using SPSS 17.0 for Windows. Shapiro- Wilk test was used to test the normality of data. The comparisons of measurement values between sexes were compared by using one-way analysis of variance (ANOVA). The Pearson Correlation Analysis was used to determine the association between stature and foot measurements. An analysis of covariance was done to test whether sex has an impact on the relationship between stature and foot measurements using GLM (general linear model). The equations for stature estimation were calculated by Linear Regression Analysis. 3 Results and discussion The results of Shapiro-Wilk test confirm the normal distribution of our data (p>0,05), so that we could use parametric tests for sex and bilateral differences as well as correlation coefficients and regression equations could be computed. Table 1 presents the descriptive statistics of all foot and footprint measurements by sex. All measurement values were higher in males than in females and these sex differences are found to be statistically significant (p<0,001). The foot length, foot breadth, footprint length and footprint breadth on the left side are higher than on right side in both sex groups, while the measurements of the foot malleol and navicular height are higher on right side. However, these bilateral differences are not statistically significant as we assumed (p>0,05). According to the non significant bilateral differences correlation coefficients and regression equations are presented for combined laterality values. Correlation between stature and foot measurements is determined by Pearson Correlation Analysis on combined right and left side in both sex groups (Table 2). All measurements exhibit statistically significant correlation coefficients with stature. Within foot measurements the highest correlation was observed for foot length in males (r = 0,716), in females (r = 0,728). Within footprint measurements higher correlation coefficient was in footprint length than in footprint breadth in males (r = 0,644) and in females (r = 0,680). The lowest correlations between the stature and foot measurements were found for foot breadth in males (r = 0,366) and for foot malleol height in females (r = 0,302). Table 3 illustrates the regression equations for stature estimation from foot and footprint measurements calculated by Linear Regression Analysis. The results of analysis of covariance (using GLM) does not show sex effects on the relationship between stature and foot dimensions (p = 0,742), so the combined data were used for the regression models. Regression coefficients are statistically significant for all parameters (p<0,05). In addition, standard errors of estimate (SEE) and Adjusted R Square are presented. The SEE predicts the deviations of the estimated stature from the actual stature. Standard errors ranged between ±4.601 cm and ±7.212 cm for pooled group. A low value of SEE indicates greater reliability 95

3 in the stature estimation. The foot length exhibits the lowest value of SEE. Thus, foot length provides optimal reliability for prediction of stature from all tested measurements. The results of the present study show that foot and footprint dimensions can be used as predictive values for stature estimation in forensic and medical investigations. However, one has to be careful because these results and the regression equations in particular can only be applied to the population from which the data have been obtained. When means of foot measurements were compared with other studies (Sen et al., 2008; Zeybek et al., 2008; Kanchan et al., 2008), differences were found between the populations. In our study we present statistically significant differences between sexes for all foot and footprint measurements. These findings are in concordance with several previous studies (Fessler et al., 2005; Sen et al., 2008; Zeybek et al., 2008; Ozden et al. 2005; Kanchan et al., 2008; Moudgil et al., 2008; Agnihotri et al., 2007). Nosignificant bilateral differences are observed in both sex groups, a result similar to those obtained by other authors (Zeybek et al., 2008; Ozden et al. 2005; Krishan et al., 2007b; Kanchan et al., 2008 ). However, Sen et al. (2008) present significant bilateral differences in foot length in their study. Moreover, statistically significant differences between right and left side were also found by Agnihotri et al. (2007) for foot length and by Kanchan et al. (2008) for foot breadth. Tab. 1 Descriptive statistics foot and footprint measurements (cm) in females and males groups Females (n=49) Males (n=36) Mean SD Min Max Mean SD Min Max rfl 24,22 1,04 22,2 26,6 26,62 1,25 23,3 29,3 lfl 24,33 1,04 22,2 26,7 26,64 1,23 23,4 29,8 rfb 9,21 0,53 7,8 10,2 10,23 0,69 8,9 11,7 lfb 9,23 0,52 8,0 10,7 10,27 0,66 8,8 11,5 rfnh 6,84 0,47 6,0 7,7 7,45 0,47 6,6 8,9 lfnh 6,85 0,45 5,8 8,0 7,41 0,52 6,4 8,7 rfmh 7,77 0,56 6,8 9,4 8,76 0,42 8,0 9,8 lfmh 7,75 0,45 7,0 8,7 8,75 0,52 7,6 10,1 rfpl 23,72 1,20 21,6 27,2 26,16 1,29 22,6 28,4 lfpl 24,5 1,22 21,7 26,9 26,26 1,17 23,4 28,8 rfpb 8,9 0,62 7,9 10,3 9,76 0,68 8,1 11,4 lfpb 9,07 0,62 7,8 10,2 9,84 0,61 8,6 11,1 Stature 168,6 6,27 158,2 186,3 180,72 6,87 168,0 197,4 rfl, right foot length; lfl, left foot length; rfb, right foot breadth; lfb, left foot breadth; rfnh, right foot navicular height; lfnh, left foot navicular height; rfmh, right foot malleol height; lfmh, left foot malleol height; rfpl, right footprint length; lfpl, left footprint length; rfpb right footprint breadth; lfpb, left footprint breadth; Min, minimum; Max, maximum; SD, standard deviation. 96

4 Tab. 2 Correlations between stature and foot/footprint measurements in females and males STATURE Foot/Footprint parameters Females (n=49) Males (n=36) Foot length 0,728 ** 0,716 ** Foot breadth 0,515 ** 0,366 ** Foot navicular height 0,420 ** 0,496 ** Foot malleol height 0,302 ** 0,449 ** Footprint length 0,680 ** 0,644 ** Footprint breadth 0,351 ** 0,401 ** ** significant at 0.01 Tab. 3 Linear regression equations for estimation of stature (cm) from foot/footprint measurements Mixed-sex group (n=85) Foot/Footprint parameters Adjusted R 2 Regression equations SEE (cm) Foot length (FL) 0,740 52, ,799 *FL 4,601 Foot breadth (FB) 0,479 95, ,036 *FB 6,510 Foot navicular height (FNH) 0,407 99, ,435 *FNH 6,942 Foot malleol height (FMH) 0, , ,808 *FMH 6,646 Footprint length (FpL) 0,678 62, ,445 *FpL 5,114 Footprint breadth (FpB) 0, , ,274 *FpB 7,211 SEE, standard error of estimate. 4 Conclusion To sum up, foot and footprint dimensions are well correlated with stature in our sample comprised of 93 Slovak males and females aged between 18 to 30 years. The length dimensions show the greatest association with stature in males and females. Analysis of covariance shows that sex does not have impact on the relationship between stature and foot/footprint measurements and so that the combined data were used for regression models. The results indicate that the stature can be predicted accurately by linear regression analysis. Population-specific regression equations for stature estimates based on foot and footprint dimensions are presented for a Slovak sample of young adult males and females. Length dimensions in particular, show a comparatively high correlation with individual s stature regardless of sex, and are therefore considered to be a reliable means for stature estimation for unidentified persons. Acknowledgement Authors are very grateful to the participants, the study could not have been carried out without their cooperation. 5 References Agnihotri, A.K. et al. Estimation of stature by foot length. Journal of Forensic and Legal Medicine. 2007; vol. 14, p Fessler, D.M.T. et al. Sexual dimorphism in foot length proportionate to stature. Annals of Human Biology. 2005; vol. l32, p Kanchan, T. et al. Stature estimation from foot dimensions. Forensic Science International. 2008; vol. 179, p. 241.e1-241e.5. 97

5 Krishan, K.a Individualizing characteristics of footprints in Gujjars of North India Forensic aspects. Forensic Science International. 2007; vol. 169, p Krishan, K. et al.b Estimation of stature from dimensions of hands and feet in a North Indian population. Journal of Forensic and Legal Medicine. 2007; vol. 14, p Martin, R. et al. Lehrbuch der Anthropologie. Stuttgart: Gustav Fischer Verlag, Moudgil, R. et al. Foot index: Is it a tool for sex determination?. Journal of Forensic and Legal Medicine. 2008; vol. 15, p Ozden, H. et al.. Stature and sex estimate using foot and shoe dimensions. Forensic Science International. 2005; vol. 147, p Özaslan, A. et al. Estimation of stature from body parts. Forensic Science International. 2003; vol.132, p Robbins, L.M. The Individuality of Human Footprints. Journal of Forensic Sciences. 1978; vol.23, no. 4, p Robbins, L.M. Estimating Height and Weight from Size of Footprints. Journal of Forensic Sciences. 1986; vol. 31, p Sen, J. et al.. Estimation of stature from foot length and foot breadth among the Rajbanshi: An indigenous population of North Bengal. In Forensic Science International. 2008; vol. 181, p. 55.e1-55.e6. Zeybek, G. et al. Stature and sex estimation using foot measurements. In Forensic Science International.2008; vol. 181, p. 54.e1-54.e5. 98