Outer and Inner Canthal Distances and their Stature Estimation Potentials among Nigerian Igbos and Ibibios Residing in Rivers State, Nigeria

Abstract

Both inner (ICD) and outer canthal distances (OCD) are some examples of facial parameters often applicable in forensic anthropology as these differ among ancestries. Despite numerous reports on stature estimation using various facial parameters across several ancestries and ethnic groups including those of Nigeria, paucity of literature on the potentials of ICD and OCD in the estimation of stature among global populations, including Nigeria, remain evident. Thus, the present study was carried out to fill this gap for two Nigerian ethnic groups, the Igbos and Ibibios. A total of 300 adults of 18 years and above (150 Igbos and 150 Ibibios) comprising 75 males and 75 females each were randomly selected. The ICD and OCD were measured between the medial canthi and lateral canthi of the palpebral fissures of the two eyes, respectively using a transparent metric rule. Stature (height) was measured using a stadiometer using a standardized method. From the results, the mean heights for the combined population of males and females were 180.57±0.74 cm and 175.28±0.65 cm respectively. The differences between sexes for height were statistically significant (p<0.05) while there was no ethnic difference in heights of both ethnic groups observed. The present study showed that the mean ICD in males and females were 3.31 cm and 3.35 cm respectively. The Ibibio males had mean ICD of 3.32 cm compared to 3.29 cm in their females. However, ICD values of Igbos showed a higher mean in females (3.42 cm) compared to males (3.30 cm). The average OCD in males for both ethnic groups were slightly higher compared to females. Significant correlations between ICD, OCD, and stature were observed in both males and females while linear regression equations for stature estimation were derived. For males, it was as follows; Stature = 23.65(ICD) + 102.177, and Stature = 3.44(OCD) + 140.932. For females, it was thus, Stature = 4.38(ICD) + 160.575, and Stature = 2.83(OCD) + 143.518. Conclusively, there were strong associations between both canthal parameters and height in both sexes irrespective of ethnic differences.