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Persona The Personalized Knee
Surgical Technique
Femur Caliper
00-5903-030-00
3.2 mm Drill
00-5120-085-00
1. Depress Collar
2. Rotate Collar
Prepare the Patella
If the surgeon determines that the condition of the
patient's patella is satisfactory, it is not necessary
to resurface the patella. The geometry, depth, and
length of the patella groove on the Persona Femoral
Component accommodates the unresurfaced patella.
Technique Tip:
These instruments are designed for
onlaying all-poly patella only.
Place the leg in full extension, evert the patella to
at least 90 degrees. Stabilize the patella, using two
inverted towel clips. Incise the soft tissue around
the patella down to the insertion of the quadriceps
and patellar tendons. Before making any bone cuts,
determine the maximum thickness of the patella by
using the femur caliper to measure the most prominent
anterior-to-posterior dimension (Figure 58).
Technique Tip:
The femur caliper has a tolerance of
± 0.25 mm.
Resect the Patella
Please refer to the appropriate surgical technique if
other patella instrumentation is to be used to resect
the patella.
Refer to the sizing chart for patella dimensions
(Figure 59). Use a 3.2 mm drill to drill the highest
portion of the medial facet perpendicular to the
articular surface approximately 12 mm deep centered
on the medial sagittal ridge (Figure 60). This acts as a
guide for proper medialization of the patella.
Use the patella osteotomy guide with the stylus set for
the desired amount of resection. Depress the button
on the stylus while twisting to set the stylus at the
desired resection level (Figure 61). If the patella is very
worn, resect less bone.
Technique Tip:
Assure that the patella osteotomy
guide stylus is referencing the most prominent
point on the patella before resecting.
Technique Tip:
At least 10 mm of bone must remain
to ensure that the pegs of the patella implant do not
protrude through the anterior surface (see image).
Figure 58
Figure 61
Figure 59
Persona Standard Implant Patella Size & Thickness
26 mm x 7.5 mm*
29 mm x 8.0 mm**
32 mm x 8.5 mm**
35 mm x 9.0 mm
38 mm x 9.5 mm
41 mm x 10.0 mm
Figure 60
* The 26 mm patella must always be inset.
** The 29 mm and 32 mm patellae must be inset when used with sizes
10–12
Persona
PS femoral components.
See package insert for complete details.
