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Persona The Personalized Knee
Surgical Technique
Size Femur – Anterior
Referencing Sizer
(cont.)
Size Femur and Establish External Rotation
(cont.)
If the 5 degrees external rotation holes are to be
used, the sizer can be positioned with the etched
line on the anterior referencing sizer 4 mm laterally
from Whiteside’s line to better center the drill holes
for subsequent anterior referencing 4-in-1 cut guide
placement, due to the M/L offset of the holes. Hold
the anterior referencing sizer in place and if necessary,
secure the anterior referencing sizer to the femur
using 25 mm x 3.2 mm (2.5 mm female hex) screws
(Figure 119) in one or both of the holes on the lower
portion of the anterior referencing sizer to help draw
the anterior referencing sizer adjacent to the distal
femur, particularly in MIS situations.
Note:
Do NOT use 48 mm screws for fixation of
the anterior reference sizer. 48 mm screws are not
recommended due to potential bone perforation.
Figure 119
Slightly extend the knee and retract soft tissues to
expose the anterior femoral cortex. Clear any soft
tissue from the anterior cortex. Ensure that the leg
is in less than 90 degrees of flexion (70 degrees
– 80 degrees). This will decrease the tension of
the patellar tendon to facilitate placement of the
anterior referencing sizer boom. The position of the
anterior referencing sizer boom tip approximates the
proximal position of the anterior flange of the femoral
component. The anterior referencing sizer boom can
be rotated to facilitate insertion under the soft tissue
envelope. A palpable indication as well as a vertical
orientation of the end of the anterior referencing
sizer boom (Figure 122) ensures that the anterior
referencing sizer boom is rotated to the correct
position.
Technique Tip:
Do not impact the anterior
referencing sizer onto the femur.
Appendix C: Optional Instruments
(cont.)
Persona Anterior Referencing Sizer
42-5099-088-00
2.5 mm Male Hex Driver
42-5099-025-00