Biomedical Engineering Reference
In-Depth Information
Fig. 1.5
Interactive orthopedic surgical planning
1.6 Simulation-Enabled Prediction and Analysis for Planning of
Orthopedic Surgery
The possibility to predict the outcomes of surgery from a pathological and biome-
chanical point of view will be a tremendous help to clinicians. Abnormal stresses
acting on articular joints are believed to be one of the origins of OA. Research shows
stress and contact analysis [
61
] can greatly improve the understanding of the pathol-
ogy [
62
-
64
] and enhance the prediction of the outcomes of surgical procedures
[
65
,
66
]. Few collision detection approaches are suitable for anatomical systems
in which soft tissues are in quasi permanent contact. Basically, detecting collisions
means checking the geometry of the target objects for interpenetration through static
interference test methods [
67
]. In our case, non rigid transformations demand special
scene structures [
68
], space partitioning [
69
] or space representation [
66
] that may
require costly update phases. The choice of the most appropriate strategy heavily
depends on the a priori knowledge on the planned surgery to make the correct sim-
plifying assumptions. With that frame in mind, the a priori knowledge of the hip
joint movement characteristics has allowed the exploitation of a spherical sampling
of the cartilage surfaces to speed-up the evaluation of the contact distribution [
70
].
Figure
1.5
shows the principles of an interactive orthopaedic surgical planning.
Because of joint deterioration, the mechanical axis no longer goes through the
middle of the knee joint. Instead, the stresses concentrate on the already damaged
compartment. Due to this concentration of stresses the cartilage damage continues
and increases. This leads to cartilage degeneration in a few years. In case of major
degenerative lesions, a total knee arthroplasty is practiced. In certain knee surgery
like high tibial osteotomy (HTO), the tibia will be cut close to the knee joint in order
to change the limb axis so that the healthy outside of the knee joint will take the load
