Measurement of the Axial Rotational Axis of Distal Femur Using Different Landmarks

Sohn, Sung Won; Jung, Myung Hyun

Abstract

PURPOSE: To know the discrepancy of rotational alignment using human femur.
MATERIALS AND METHODS
We used 22 adult human femurs which were not able to distinguish age and sex and absent articular cartilage. In a horizontal plane, we made a cross-section perpendicularly at supra-condyle of femur to a mechanical axis and took a simple roentgenogram in coronal plane focusing on the center of transepicondylar axis. In terms of roentgenogram and gross specimen, the angle between per-pendicular to the anteroposterior axis and the posterior condylar axis, the angle between the transepi-condylar axis and the posterior condylar axis were measured by 5 observers. According to t-test in statisti-cal method, we figured out the difference between two angles and made a significance at p<0.05.
RESULTS
About posterior condylar axis, the line perpendicular to anteroposterior axis was observed the average 4.8(+/-1.5)degree, 6.0(+/-1.9)degree external rotation in roentgenogram and gross specimen respectively. The transepicondylar axis was observed the average 3.5(+/-1.2)degree, 3.9(+/-1.4)degree external rotation in roentgenogram and gross specimen respectively. There was statistically significant difference between two angles. Moreover, angles measured by 5 observers were found that to have a line perpendicular to the anteroposterior axis has much more external rotation respectively and there was a statistically significant difference also.
CONCLUSIONS
On determination of a rotational alignment using human femur, there is statistically sig-nificant difference between the anteroposterior axis and the transepicondylar axis in gross specimen as well as roentgenogram.