CORRELATION OF HUMAN HEIGHT WITH FOOT LENGTH IN INDIAN INDIVIDUALS

Introduction: The height estimation is as important as other parameters like age, sex and race especially in medico-legal cases. The environmental and genetic factors influence the development of various parts of body. Although bilateral symmetry is a feature seen in humans, there is asymmetry in the foot length without gender or handedness bias. Aim: To study the relationship of human height with foot length and to derive a mathematical module to predict the height from foot length. Materials and Methods: This is a Cross-sectional study carried out in Ramaiah Medical College, Bangalore in 234 individuals aged between 18 and 25 years of age. Descriptive statistics, Pearson’s correlation coefficient and linear regression were employed for the Statistical analysis of the data Results: The overall mean foot length observed was 22.82 ±1.10 cms. There was significant difference in the mean values between right and left foot length which was statistically significant (P value = <0.001). The height showed a statistically significant positive correlation with left foot length in both males and females. Linear regression equation was derived to predict height from foot length in both males and females. Conclusion: In the present study, there was a statistically significant difference in right and left side mean foot length measurements in both sexes. A positive correlation was observed between height and foot length and left foot length had better correlation with height in both sexes. It was concluded from further analysis that other parameters need to be considered for better predictability of height.


INTRODUCTION
studies by various authors [2].There are also various studies of stature estimation from foot length and breadth, small bones of foot and foot prints [3].The height estimation is as important as other parameters like age, sex and race especially in medico-legal cases [4].The environmental and genetic factors influence the development of various parts of body [3].Sex determination can be done from foot index, foot shape and foot bones.Although bilateral symmetry is a feature seen in humans, there is asymmetry in the foot length without gender or handedness bias [2].Rutishauser has documented that stature estimation from foot length and length of long bones share same reliability.As foot ossification and maturation is earlier compared to that of long bones in adolescent age group, foot length can be used to predict stature of an individual [5].The foot length has been correlated with weight and height even in dead fetuses thereby making possible the estimation of foetal age and body dimensions with precision [6].Aim: To study the relationship of human height with foot length.To derive a mathematical module to predict the height from foot length.
Height: The height of the participant was measured in centimetres (cms) using Stadiometer -a wall mounted height measuring device.The measurements were taken three times to avoid intraobserver variation and their mean value has been considered.Data so collected has been entered in a master chart in Microsoft® Excel and has been analyzed using the SPSS version 17.0.Informed consent has been taken from all participants.The ethical clearance has been obtained from the institution.Statistical Methods: Descriptive statistics such as mean and standard deviation has been computed for height and foot length Pearson's correlation coefficient has been used to find the correlation between stature and foot length.Multiple Linear regression has been used to predict height from foot length of an individual  8), the correlation co-efficient varied from 0.4 to 0.6.Assuming the correlation co-efficient to be around 0.58 with the power of 80% and alpha error of 5, sample size was estimated to be 234.Criteria: Inclusion criteria: Individuals aged between 18 and 25 years in and around Bangalore, Exclusion criteria: Individuals with features suggestive of dysmorphic syndromes Parameters studied: Foot length: Foot length was measured in centimetres (cms) using a calibrated foot board.

RESULTS
The study consisted of 234 subjects, out of which 136 were males and 98 were females.The overall mean foot length observed was 22.82 ±1.10 cms.Mean length of foot between the two sides were compared and it was found to be 24.95 ±1.15 cms for right foot and 20.70±0.94cms for left foot and t test revealed that there was significant difference in the mean values between right and left foot length which was statistically significant(P value = <0.001)(Table -1) There was no significant difference in mean values of right foot in males and females and the same was observed with left foot length of males and females (Table -2).The height and mean foot length showed a positive correlation on both sides (p=0.249 on right side; p=0.264 on left side) which was statistically significant (Table -3 The co-efficient of determination obtained for the above regression equations were found to be 0.04, which indicates that the proportion of variability in the height that can be explained by foot length alone is only 4%.Hence, it can be concluded that other parameters need to be considered for better predictability of height.A highly significant correlation (p<0.0001) has been documented between hand length and foot length on both sides and in both sexes by Anitha et al [2] and hence if one is known the other can be predicted.Patel SM et al [5] and Utsav Parekh et al [4] have reported a statistically significant correlation between foot length and height in individuals from various regions of Gujarat.Shailesh M Patel et al [9] have found that there is a strong association between foot length and foot breadth and also between stature and foot breadth.They have opined that stature can be more accurately calculated by foot breadth than by long bones.have concluded that the height of an individual is 6.5 times the length of their foot.Charu Taneja et al [14] have reported a positive correlation between stature and foot length in male tribals of Udaipur district of Rajasthan.
Rakhee Verma et al [15] have reported that foot length is a reliable predictor of stature in both sexes.Twisha Shah et al [3] have stated that if shoulder width, foot length or arm length is known, height and sex can be calculated.Harshvardhan et al [1] have concluded that the foot length provided medium reliability and accuracy in estimating stature in males and females.In the present study, a positive correlation between height and foot length has been reported and regression equations have been derived similar to other studies reported.(Tab.5)

DISCUSSION
There was a statistically significant difference in right and left side mean foot length measurements in both males and females.A positive correlation between height and foot length was observed which was statistically significant.The left foot length had better correlation with height in both sexes.It was concluded from further analysis that other parameters need to be considered for better predictability of height.

CONCLUSION Conflicts of Interests: None
Access this Article online Quick Response code International Journal of Anatomy and Research ISSN (E) 2321-4287 | ISSN (P) 2321-8967 https://www.ijmhr.org/ijar.htmDOI-Prefix: https://dx.doi.org/10.16965/ijarDOI: 10.16965/ijar.2017.516 MATERIALS AND METHODSStudyDesign: Cross-sectional study Source of data: Individuals aged between 18 and 25 years of age in and around Bangalore Place of study: Ramaiah Medical College, Bangalore Duration of study: 6 months Sample size: Based on a previous studies conducted by Harsh Vardhan et al(1), Meena et al(7) and Suman Babu et al( ).The height showed a positive correlation with left foot length in males which was statistically significant (r=0.196,p = 0.022) (Table -4).Similarly, correlation of height with foot length in females also revealed a statistically significant positive correlation on left side (r=0.244,p=0.016) (Table-4).Linear regression equation was derived to predict height from foot length in both males and females.Regression equation to predict height in males, right foot: Y (height) = 0.233+ {(-0.068X right foot length)} Girish Shiv Shankar, Veena Vidya Shankar, et al., CORRELATION OF HUMAN HEIGHT WITH FOOT LENGTH IN INDIAN INDIVIDUALS.Regression equation to predict height in males, left foot: Y (height) = 1.033+ (0.251 X left foot length) Regression equation to predict height in females, right foot: Y (height) = 0.019 + (0.003 X right foot length) Regression equation to predict height in females, left foot: Y (height) = 1.85+ (0.241 X left foot length)

Table 2 :
Mean measurements of right and left foot lengths in males and females.

Table 3 :
Correlation of height with right and left foot length.

Table 4 :
Correlation of height with right and left foot length in males and females.

Table 5 :
Various studies of correlation between foot length and height.