Relationships between the three-dimension morphologic parameters of proximal femurs

To measure the three-dimensional morphologic parameters of proximal femurs and analyze the correlations between these parameters, as well as differences with the aging, which can provide the basic data and reference for the prediction of proximal femoral strength. 20 healthy males with no history of hip disease were selected, whose range of ages was 61-80. The proximal femur of each subject was scanned using clinical QCT (GE Medical System/LightSpeed16). All right proximal femurs of subjects were selected to do 3D reconstruction. Three-dimensional morphologic parameters of proximal femurs were measured and an auxiliary line was drawn according to these obtained data using our self-designed algorithm. Thus, three-dimensional morphologic parameters of proximal femurs can be measured accurately. There are 8 parameters measured and calculated including diameter of femoral head (HD), height of femoral head (HH), distance of head center from shaft axis (OFF), neck shaft angle measured as angle between neck and shaft axis (NSA), height of the top of the greater trochanter above a line perpendicular to the shaft axis and passing through the head center (TRH), thickness of the femur 25mm below the lower edge of the lesser trochanter (TOF), diameter of the most narrow end of neck(ND), length of neck(NL). The 20 samples were divided into two independent age groups. A group of subjects were 61-70 years old and B group of subjects were 71-80 years old. These two groups of samples were performed Two-Independent-Samples Non-parametric Tests (Mann-Whitney U Tests) to determine the differences between the 3D morphologic parameters. The 20 samples were performed correlation analysis between each two parameters. There are no significant differences between two groups in all parameters except ND. There are significant correlations between most parameters at the significant level of 0.01 and 0.05 when performed correlation analysis. Three-dimensional morphologic parameters of proximal femur can be measured more accurately by using the self-defined measurement rules and self-developed algorithms. From the analysis results we can find out that three-dimensional morphologic parameters of proximal femurs in different age groups are of differences. Meanwhile there are significant correlations between some of the parameters. This can provide data references of geometry factors affecting strength of proximal femur for the future analysis.