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Persona The Personalized Knee
Surgical Technique
Introduction
(cont.)
Note:
The MC components can be used with or
without the PCL present. The UC, PS, and CPS
components should not be used if the PCL is
present.
Please refer to the package inserts for complete
product information, including contraindications,
warnings, precautions, and adverse effects.
Preoperative Planning
Obtain 36 inch or 53 inch standing anteroposterior
and lateral radiographs of the extremity, as well as a
sunrise view of the patella. The entire femur should
be visualized to rule out any structural abnormalities,
as the distal femoral cut will be referenced from an
intramedullary rod in the medullary canal.
Use the template overlay (available through your
Zimmer Biomet representative) to determine the
angle between the anatomic axis and the mechanical
axis. This angle will be reproduced intraoperatively.
This surgical technique helps the surgeon ensure
that the distal femur will be cut perpendicular to the
mechanical axis and, after soft tissue balancing, will be
parallel to the resected surface of the proximal tibia.
Surgical Approach
The surgeon can choose a midvastus approach, a
subvastus approach, or a parapatellar medial
arthrotomy. Also, depending on surgeon preference,
the patella can be either everted or subluxed. The
femur, tibia, and patella are prepared independently,
and can be cut in any sequence using the principle of
measured resection (removing enough bone to allow
replacement by the prosthesis).
Patient Preparation
To prepare the limb for total knee arthroplasty,
adequate muscle relaxation is required. The
anesthesiologist should adjust the medication based
on the patient’s habitus and weight, and administer
to induce adequate muscle paralysis for a minimum
of 30-40 minutes. It is imperative that the muscle
relaxant be injected prior to inflation of the tourniquet.
Alternatively, spinal or epidural anesthesia should
produce adequate muscle relaxation. If desired, apply
a proximal thigh tourniquet and inflate it with the
knee in hyperflexion to maximize that portion of the
quadriceps that is below the level of the tourniquet.
Once the patient is draped and prepped on the
operating table, determine the landmarks for the
surgical incision.