Objective The morphology and quantitative anatomy of the axis vertebra (C2) attracts a lot of attention between anatomists, surgeons and radiologists. However, no report exists in the literature correlating the height of the dens with the length of the femur. Our paper aims to determine such a correlation. Material and methods An examination of forty-five adult dry skeletons (twenty-three male and twenty-two female) was conducted. The height of the odontoid process of the axis and the maximum length of the femur were measured and statistically analyzed. Results The mean values for the height of the dens were 19.13±2.74 mm and 16.83±2.45 mm concerning the male and female dry skeletons respectively. The mean maximum length of the right femur bone was 43.04±2.32 cm for male and 39.90±2.40 cm for female skeletons. Data analysis revealed a statistically significant correlation (r=0.709, p <0.001) between the height of the odontoid process and the maximum length of the femur bone. A linear regression model expressing this association was created: Femur max length (in cm) = 32.874 + 0.531 x Dens height (in mm). Conclusion We present a new mathematical equation correlating one of the most studied long bones of the skeleton, the femur, with another "long" part of the bony structure of the human body- the C2 odontoid process., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2020, Vasilopoulos et al.)