17
CT-free Registration
NAVIO’s™ CT-free registration process utilizes
standard image-free principles in constructing
a virtual representation of a patient’s anatomy
and kinematics. The user may choose to
move through the software’s workflow via
the included NAVIO system footpedal or the
touchscreen controls. Any collected point
may be re-collected in sequence by moving
backwards through the workflow stages.
Femur Neutral Position
Place the leg in full extension, applying slight
axial pressure to both compartments. Support
the leg below the knee with one hand to avoid
hyper-extension. This position will be utilized
when calculating the patient’s preoperative
varus / valgus deformity. Press and hold the
right footpedal to collect the position (Figure
18). When the bar on the bottom reads as fully
green (100%), release the footpedal to allow the
software to automatically proceed to the next
workflow step.
Hip Center
The Hip Center Calculation stage will follow
the femoral tracker array through circular
movements of the hip. These circular
movements should be unrestricted and
unhindered by holding/fixing equipment. Avoid
pelvic movement, which can be a source of
error.
Prior to beginning collection, the femur should
start in approximately 20º of hip flexion in order
to provide enough room to rotate the hip in a
wide circle. Slowly rotate the leg at the hip until
all sectors of the graphic have changed to green
(Figure 19).
There should be no transmission of force from
the femur onto the pelvis. Avoid a hip flexion
angle greater than 45º.
Figure 18.
Figure 19.
4
Registration
