It is very important to obtain a reliable geometric data of the femoral canal for designing femoral component in total hip arthroplasty. So author estimated the shape and measured the size of the proximal femoral canal using 3 dimensional images
obtained from computerized tomographic data of 60 korean normal adult cadaveric femora. EXTRACT II PROGRAM VERSION 2.5 BY CORNELL UNIVERSITY at the SUN 3 WORK STATION was used for this study.
Author demarcated the margin of the cortical and cancellous bone on the threshold value 40 at the EXTRACT II PROGRAM and defined the guide line and guide point, estimated and measured the parameters with 3 axis coordinate system such as femoral
length,
anteversion of the femoral head, neck shaft angle, and femoral offset etc.
Entire femoral length was average 41.6±25.2mm, ranging from 358.6mm minimally to 465.1mm maximally. The femoral anteversion angle was average 20.53±9.11°ranging from 。。 to 36.5。. The neck-shaft angle was average 127.8±5.7。, ranging from
115.5。
to 139.0。 . The length of temoral offset was average 37.5±5. 2mm. The length of transverse diameter measured at the center of lesser trochanter was average 29.4±3.5mm and measured at 20mm above the lesser trochanter was average 47.3±4.6mm.
The
isthmic position was olcated at 109.3±13.1mm below the center of the lesser trochanter and the transverse diameter at the isthmic position was average 12.1±2.1mm in mediolateral derection and 14.4±2.4mm in anteroposterior direction. The
average
of
canal flare imdex which indicates the shape of porximal femoral canal, was 3.8±0.7; stove-pipe shape was 8.4%, normal shape was 70.0% and Champagne-flute shape was 21.6%
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