Original ArticleThe Functional Flexion-Extension Axis of the Knee Corresponds to the Surgical Epicondylar Axis: In Vivo Analysis Using a Biplanar Image-Matching Technique
Section snippets
Simulation of Knee Motion Using a Biplanar Image-Matching Technique
Nine healthy male Japanese volunteers with an average age of 32 years (range, 25-43 years) were the subjects in this study. Computed tomography (CT) scan images of the left knee of each subject were made at levels ranging from 80 mm proximal to the joint to 80 mm distal to the joint (Hispeed Advantage, GE Medical Systems, Inc, Milwaukee, Wis). These scans were made at 2-mm intervals with a 1-mm-wide source beam so that the functional axis of lower extremity (the femoral head to midankle plafond
Results
The functional flexion-extension axis was identified successfully for all subjects. The radius of the optimal circle was 380 ± 11 mm and percentage error was 0.61% ± 0.23%. The functional flexion-extension axis was found in all cases to pass through the posterior femoral condyles. When the axis was viewed end on, each femoral condyle was found to conform to the perimeter of a circle with a common center on the axis. However, the most posterior aspects of the femoral condyles, which contact the
Discussion
Some analyses of the knee, based on cadavers, have shown that the knee has a fixed flexion-extension axis in the posterior femoral condyles and that this fixed axis coincides with the transepicondylar axis 5., 6., 7., 8., 9.. Elias et al [5] found isometric points on the distal femur, which suggested a fixed flexion-extension axis located in the posterior femoral condyles. Stiehl and Abbott [7], in their anatomical study, showed that the transepicondylar axis parallels the knee
Acknowledgments
We thank Y Yukawa and J Kinoshita, (Kyoto University Hospital, Kyoto, Japan) for their technical assistance and advice in radiographs. We also thank M Taniguchi for his technical assistance and advice in CT scanning.
References (30)
- et al.
A three-dimensional study of the knee kinematics of the human knee
J. Biomech.
(1975) - et al.
Methods, difficulties and inaccuracies in the study of human joint kinematics and pathokinematics by the instant axis concept. Example: the knee joint
J. Biomech.
(1979) - et al.
Morphology of the transepicondylar axis and its application in primary and revision total knee arthroplasty
J. Arthroplasty
(1995) - et al.
Implications of reference axes used for rotational alignment of the femoral component in primary and revision knee arthroplasty [see comments]
J. Arthroplasty
(1992) Flexion space configuration in total knee arthroplasty
J. Arthroplasty
(1995)- et al.
Location of the femoral sulcus in the osteoarthritic knee
J. Arthroplasty
(1996) - et al.
Geometry and motion of the knee for implant and orthotic design
J. Biomech.
(1985) - et al.
Biomechanics of internal derangement of the knee. Pathomechanics as determined by analysis of the instant centers of motion
J. Bone Joint Surg. Am.
(1971) - et al.
The rotation axis of the knee and its significance to prosthesis design
Clin. Orthop.
(1972) - et al.
A correlative study of the geometry and anatomy of the distal femur
Clin. Orthop.
(1990)
The axes of rotation of the knee
Clin. Orthop.
A compound pinned hinge model of knee joint kinematics
Trans. Orthop. Res. Soc.
The transepicondylar axis approximates the optimal flexion axis of the knee
Clin. Orthop.
The anatomy and functional axes of the femur
J. Bone Joint Surg. Am.
Determining the rotational alignment of the femoral component in total knee arthroplasty using the epicondylar axis
Clin. Orthop.
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