Persistent Metopic Suture in Adult Cadaveric Dry Skulls of Coastal Karnataka

Metopism in adult South Africans and its relationship to frontal sinus size

“…Thus, Agarwal et al (1979) noted that it was situated "almost exclusively" in the lower part of the frontal above nasion and Yadav et al ( 2010) reported it to be just above nasion in 95.95% (142/148) of specimens examined by them. In all other studies in which the incomplete suture has been documented, it is clearly located immediately superior to nasion in all cases (Ajmani et al, 1983;Aksu et al, 2014;Andrade et al, 2019;Burrell et al, 2016;Castilho et al, 2006;Chandrasekaran & Shastri, 2011;del Sol et al, 1989;Kumar & Rajshekar, 2015;Maneenin et al, 2013;Mangalgiri et al, 2010;Pilli & Sunder, 2013;Saikia, 2014;Santhosh et al, 2014;Surekha et al, 2016;Vinoth et al, 2014;Zanaty, 2017). A variety of terms have been employed by various workers to describe the configuration of an incomplete metopic suture that extends upwards from nasion (Table 1).…”

“…Nevertheless, the variation in frequencies that have been recorded for numerous independent samples from India (Table 8) suggests that the identification of incomplete metopism differs quite widely among researchers using the same type of material (e.g., dried crania). Thus, for example, incidences of 7.0% and 42.9% have been reported for samples of dry crania from Karnataka State in southwestern India by Santhosh et al (2014) and Andrade et al (2019), respectively. Similarly, a complete absence of remnant metopism in a cranial sample from Malawi (Odokuma & Igbigbi, 2008) is quite unexpected given the incidence reported here for South Africa, which is just over some 1800 km distant.…”

“… Note : Studies: 1, Ajmani et al (1983); 2, Castilho et al (2006); 3, Mangalgiri et al (2010); 4, Chandrasekaran and Shastri (2011); 5, Maneenin et al (2013); 6, Pilli and Sunder (2013); 7, Aksu et al (2014); 8, Kumar and Rajshekar (2015); 9, Saikia (2014); 10, Santhosh et al (2014); 11, Vinoth et al (2014); 12, Burrell et al (2016); 13, Surekha et al (2016); 14, Zanaty (2017); 15, Andrade et al (2019). …”

“…The incidence of incomplete metopism in the South African sample is 28.8 times higher than its frequency of complete metopism. This difference is exceeded by only two other samples: the Karnataka Indian sample of Andrade et al (2019) at 30Â, and the Tamil Nadu sample of Vinoth et al (2014) at 44Â. At the same time, however, the incidence of incomplete metopism is lower than that for complete metopism in only three samples reported to date-those for Malawi (Odokuma & Igbigbi, 2008), the Bedouin (Arensburg et al, 1977), and India (Sheshgiri & Shisirkumar, 2014).…”

“…Given the variety of remnant sutural forms that have been recognized by different workers (Table 1), it is difficult to translate some of these categories into the two nonlinear forms (i.e., double and diffuse) employed in the present study. This seems to be especially the case with reference to the forms that have been recognized as being "Y-shaped" and "T-shaped" (Andrade et al, 2019;Mangalgiri et al, 2010;Pilli & Sunder, 2013). Nevertheless, if one assumes that the currently recognized double form includes the categories "U-shaped," "V-shaped," "Double," "Double U-shaped," and "Inverted U," and that the currently recognized diffuse form includes the categories "H-shaped," "Double Zig-Zag," and "Wide Side to Side" it is possible to perhaps gain some kind of idea as to the comparability of the frequencies in the three T A B L E 9 Length (mm) of remnant metopic sutures in the combined sex South African and the combined sex Indian sample of Pilli and Sunder (2013).…”