Fig 1.
The schematic workflow of computer assisted planning of PAO with biomechanical optimization.
(A) Computer assisted morphology based PAO planning. Virtual osteotomy operation is done with a sphere, whose radius and position can be interactively adjusted, and virtual reorientation operation is done by interactively adjusting anteversion and inclination angle of the acetabulum fragment. (B) Biomechanical optimization. (C) the pre-operative planning output.
Table 1.
Acetabular morphological parameters of ten specimen with hip dysplasia.
Fig 2.
Biomechanical simulation of contact pressure on acetabular cartilage.
(A) Surface models of a dysplastic hip; (B) Volume meshes of a dysplastic hip. (C) Surface models for a planned situation after acetabulum fragment reorientation. (D) Volume meshes for the planned situation. (E) Boundary conditions and loading for biomechanical simulation. (F) Coarse meshes for bone models, and refined meshes for cartilages.
Fig 3.
Contact pressure distribution obtained by using two different cartilage models at different acetabular reorientation position.
Table 2.
Acetabular fragment reposition position with peak contact pressures and contact area.
Fig 4.
(A) Scatter plot of peak contact pressure obtained by constant thickness cartilage models against those obtained by patient specific cartilage models. (B) Scatter plot of contact area obtained by constant thickness cartilage models against those obtained by patient specific cartilage models.
Table 3.
Acetabular fragment reposition position with peak contact pressures and contact area (Patient specific cartilage model vs. Constant thickness cartilage model).