Osteometric Morphometry of Dry Adult Tibiae in a South Indian (Andhra Pradesh) Population: A Cross-Sectional Study

Background: Population-specific osteometric data of the tibia are essential for forensic anthropology, orthopaedic implant design, and clinical anatomy. This study aimed to investigate the morphometric parameters of dry adult tibiae in a South Indian (Andhra Pradesh) population using simple, cost-effective instruments. Material and Methods: The study was conducted on 100 dry adult tibiae (50 right and 50 left) of unknown sex. Measurements were performed using an osteometric board, digital vernier calipers (accuracy 0.01 mm), flexible measuring tape, and thread. Seven linear parameters and two derived indices were recorded: maximum tibial length, antero-posterior and medio-lateral diameters at the nutrient foramen, circumference at the nutrient foramen, proximal and distal epiphyseal breadths, distance from proximal end to nutrient foramen, cnemic index, and foraminal index. Data were analysed using descriptive statistics and side-wise comparison. Results: The mean maximum tibial length was 369.5 ± 24.5 mm (range: 325–428 mm). The mean antero-posterior diameter, medio-lateral diameter, and circumference at the nutrient foramen were 28.4 ± 3.1 mm, 20.6 ± 2.9 mm, and 84.5 ± 8.2 mm respectively. Proximal epiphyseal breadth averaged 71.8 ± 5.6 mm and distal epiphyseal breadth 54.2 ± 4.8 mm. The nutrient foramen was located in the proximal third in 78% of bones. The mean cnemic index was 72.5 ± 10.8, indicating a predominantly mesocnemic tibial shaft morphology. No statistically significant bilateral differences were observed in any parameter (p > 0.05). Conclusion: This study provides baseline osteometric reference values for dry adult tibiae in the South Indian (Andhra Pradesh) population. The findings demonstrate bilateral symmetry, moderate size variation, mesocnemic shaft type, and consistent proximal-third location of the nutrient foramen. These population-specific data will be valuable for forensic identification, anthropological comparisons, and orthopaedic surgical planning in the region.

Keywords: Tibia, Osteometry, Morphometry, Nutrient foramen, Cnemic index, South Indian population, Andhra Pradesh, Forensic anthropology.