Radiological assessment of the femoral bicondylar angle in a Nigerian population

Abstract

Background: Femoral bicondylar angle is the angle between the diaphysis of the femur and a line perpendicular to the infracondylar plane. It is indispensable in bipedal locomotion as it serves to place the knee and foot under the body’s center of gravity during the single support phase of gait. Although the mechanism for the formation of the angle is poorly understood it is believed to be an effect of the stresses in the physis of the distal femur resulting from bipedal loading conditions. This angle is believed to vary in individuals, gender and races. At birth, the femoral bicondylar angle is 0⁰ but reaches a maximum of 14⁰ in adults.
Objectives: To document data for the femoral bicondylar angle of Nigerians in Rivers State and to establish if there exists any sexual dimorphism or racial variation in the femoral bicondylar angle amongst Nigerians in Rivers State.
Materials and Methods: A total of 250 radiographs of the knee joints were collected and reviewed from November 2010 to August 2011.
Results: The gender difference observed was statistically significant  (F=11.720, p=0.001). The mean bicondylar angle of the right femur for males was 8.35± 0.242⁰ while that of the right femur for females was observed to be 8.16 ± 0.8187⁰. Results also revealed that the mean for left femoral bicondylar angle in males was 8.66 ± 0.231⁰ while that of females was 8.91 ± 0.185⁰. These findings reveal that there exists sexual dimorphism in the femoral bicondylar angle amongst Nigerians in Rivers State. In addition, observation also showed that there existed racial variation when compared to other races in the world.