Deformity Parameters

Record the deformity parameters here, by overlaying the x-rays and the generated matching views, and reading the bone segment coordinates from the grid. The software will then generate the matching views again, this time with the bone segments shown for checking. Note that this will take some time.

In the matching views, the blue circles show the x-ray nearest points, and the red circle the target point which is also the origin of the 2D coordinate grid. Confirm that the grid spacing is 20mm, align the printed and x-ray images, and read the coordinates from the grid. The x axis is across the A3 page, the z axis up it. The y axis is the line between x-ray source and target point.

If you enter a frame identifier for which you have previously defined deformity parameters, and leave the data fields empty, then the saved data will used and can be edited if required. Enter example-frame for example definitions.

Frame identifier

The bone segments attached to each fixator ring are defined by initial coordinates X1,Z1 and X2,Z2. After deformity correction, the X1,Z1 corresponding points will be brought into contact, or be separated by the axial extension, and all the points will lie on a straight line. The X2,Z2 points just define segment alignment in each view. They can be anywhere along each segment away from the X1,Z1 points. Bone segment 1 is attached to ring 1 (lowest in the generated graphics), and segment 2 to ring 2 (highest). Dimension units are mm.

Frontal view:

Bone segment 1: X1 Z1 X2 Z2

Bone segment 2: X1 Z1 X2 Z2

Lateral view:

Bone segment 1: X1 Z1 X2 Z2

Bone segment 2: X1 Z1 X2 Z2

When the deformity correction is complete, the X1,Z1 corresponding points will be separated by the value of this optional axial extension. Dimension units are mm.

Axial extension

When the deformity correction is complete, the upper bone segment attached to ring 2 will be rotated axially with respect to the lower by this rotation angle. Looking down from above, from ring 2 to ring 1, clockwise rotations are positive. Rotation units are degrees.

Axial rotation