Biomechanical simulation of contact pressure on acetabular cartilage.

<p>(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.</p

The schematic workflow of computer assisted planning of PAO with biomechanical optimization.

<p>(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.</p

Contact pressure distribution obtained by using two different cartilage models at different acetabular reorientation position.

<p>Contact pressure distribution obtained by using two different cartilage models at different acetabular reorientation position.</p

Scatter plot of 2.5D measurements of the FHC from different views against 3D measurements of the FHC on patient group.

<p>Scatter plot of 2.5D measurements of the FHC from different views against 3D measurements of the FHC on patient group.</p

Bias, precision and Pearson correlation coefficient between the 2.5D and the 3D measurements of FHC on both the control and the patient groups.

<p>Bias, precision and Pearson correlation coefficient between the 2.5D and the 3D measurements of FHC on both the control and the patient groups.</p

Bias, precision and Pearson correlation coefficient between 3D measurements of FHC and 2.5D measurements of FHC on the patient group using different oblique views.

<p>Bias, precision and Pearson correlation coefficient between 3D measurements of FHC and 2.5D measurements of FHC on the patient group using different oblique views.</p

Hip²Norm Software.

<p>(A) Graphical user interface (left image) for digitizing landmarks for computerized evaluation of an AP radiograph of the pelvis. The inferior margins of the teardrops (red crosses), the outline of the projected anterior and posterior acetabular rim (blue and red line), and the middle of the sacrococcygeal joint (upper blue cross) and the upper border of the symphysis (lower blue cross) must be drawn manually, while the center and the radius of femoral head (pink cross) and acetabulum (green cross) are obtained by fitting a circle to three points specified by the user. (B) Anterior and posterior acetabular rims, and 2.5D measurements of FHC after neutralizing the pelvic position (right image).</p

DRRs with different amounts of pelvic tilt.

<p>(A) Schematic view of DRR by controlling the projection parameters. (B) AP view (0° of pelvic tilt). (C) T-10 oblique view (-10° of pelvic tilt). (D) T+10 oblique view (10° of pelvic tilt).</p

Average localization error (MLD with SD: mm) when evaluated on 10 3D CT data.

<p>Average localization error (MLD with SD: mm) when evaluated on 10 3D CT data.</p

A schematic illustration on how to compute the visual feature of a sampled 3D image patch for RF training and regression.

<p><b>Left</b>: a sub-volume is sampled from a MRI/CT volume. <b>Middle</b>: we divide the sampled image patch into <i>k</i> × <i>k</i> × <i>k</i> blocks. <b>Right</b>: for each block, we compute its mean and variance using the integral image technique.</p