Morphometric Examination of adult human dry forearm bone in Indian origin for sex determination

Abstract

Background: Morphometric assessment of the radius and ulna provides important anatomical information and may help in understanding sexual dimorphism, bilateral asymmetry, forensic identification, anthropological assessment, and orthopedic applications. However, morphometric characteristics may vary among different populations. The present study evaluated selected morphometric parameters of adult dry radius and ulna bones from a Central Indian population and assessed sex- and side-related differences. Aim: To evaluate selected morphometric parameters of adult dry radius and ulna bones and determine the presence of sexual dimorphism and bilateral asymmetry in the studied population. Materials and Methods: This observational morphometric study was conducted using 100 adult human dry ulna bones and 100 adult human dry radius bones obtained from the osteological collections of Ram Krishna Medical College Hospital & Research Centre, Bhopal, Madhya Pradesh. Bones with complete anatomical integrity and identifiable sex and side were included. Morphometric parameters were measured using a digital Vernier caliper following standardized anatomical landmarks. Measurements included maximum length, olecranon width, coronoid height, midshaft diameter, and distal end breadth for the ulna, and maximum length, head diameter, neck circumference, midshaft diameter, and distance from the radial head to the bicipital tuberosity for the radius. The measurements were compared between male and female bones and between right and left sides using appropriate statistical tests. Results: Male ulnae showed higher mean values than female ulnae for maximum length, olecranon width, coronoid height, midshaft diameter, and distal end breadth. Similarly, male radii demonstrated higher mean values than female radii across the assessed morphometric parameters. For the radius, statistically significant sex-related differences were observed in maximum length (243.65 vs. 223.60 mm), head diameter (23.10 vs. 21.20 mm), neck circumference (37.80 vs. 35.00 mm), midshaft diameter (9.70 vs. 8.90 mm), and distance from the radial head to the bicipital tuberosity (29.30 vs. 27.60 mm). The right-sided measurements were generally slightly greater than the corresponding left-sided measurements, suggesting possible bilateral asymmetry; however, the significance of side-related differences varied across individual parameters. Conclusion: The present study demonstrates appreciable sexual dimorphism in the morphometric characteristics of adult radius and ulna bones, with males generally exhibiting greater dimensions than females. The observed bilateral differences may reflect functional or developmental asymmetry. These morphometric parameters may have potential applications in forensic anthropology, anatomical research, orthopedic planning, and population-specific skeletal identification.

Keywords: Radius; Ulna; Morphometry; Sexual Dimorphism; Bilateral Asymmetry; Osteology; Forensic Anthropology; Central Indian Population.