Anthropological Variations of the Inner and Outer Canthal Distance of the Igbos of South-Eastern Nigeria

Abstract

This study is concerned with generating a database for outer and inner canthal dimensions for the Igbos of south-eastern Nigeria. The study was determined in 3000 normal subjects comprising 1500 males and 1500 females of ages 7-40 years Six hundred subjects were selected from each of the five south-eastern states of Nigeria were the Igbos are dominant to make up the 3000 subjects. The sample size from each state comprised of 100 males and 100 females for each group comprising of adults (26-45 years), young adults (16-25 years) and children (7-15 years). Measurement was done directly on subjects with a non-stretchable plastic ruler. The mean inner canthal distance for Igbo males are 3.54+.49cm, 3.85+.37cm and 4.04+.29cm while females recorded 3.58+.39cm, 3.82+.29cm and 3.91+.21cm, in children, young adults and adults respectively. The overall inner canthal distance value irrespective of age (7-40 years) in male was 3.81+.44cm while in female it was 3.74+.34cm; this value was significantly higher in male than in female. The mean outer canthal distance for 1gbo male was found to be 10.27+.66cm, 11.21+.48cm and 11.61+.43cm and for female, 10.33+.58cm, 11.08+.36cm and 11.33+.27cm were recorded for children, young adults and adults respectively. There was significant sexual dimorphism observed in adults only (P< 0.05). Comparisons of these values to the reported values of other ethnic groups in Nigeria shows that ethnic variations exist for both inner and outer canthal measurements. This work has generated normative values of inner canthal distance and outer canthal distance for the Igbos of south-eastern Nigeria. This would be of benefit not only to the maxillofacial and plastic surgeons, but also to the anthropologist and dysmorphologist.