Zimmer Biomet NexGen MIS LPS-Flex, Руководство по хирургической технике

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NexGen MIS LPS-Flex Mobile Implant System
Surgical Technique
Incision and Exposure
The skin incision can be made at the surgeon’s
discretion with the leg in flexion or extension. Most
surgeons find it easier to make the incision with the
knee flexed. This provides skin tautness, and some
retraction on the skin edges.
The initial incision is based on palpable landmarks
and should initially extend approximately 1 cm below
the joint line and 1 cm above the superior pole of
the patella with the knee flexed. In a well-placed
incision with supple soft tissues, this incision length
can be adequate for the procedure. Larger amounts of
subcutaneous fat, large amounts of fibrotic synovium,
or thick inelastic quadriceps musculature may require
more generous exposure and the surgeon must be
cautious in retraction to avoid excessive tension on
the skin.
Adjustments in incision placement may be performed
by incision lengthening and repositioning as exposure
proceeds. Raising full thickness flaps along the length
of the incision improves mobility of the patella and
facilitates partial eversion for patellar preparation while
simultaneously improving mobility of the skin and
reducing tension on the skin flaps during minimally
invasive exposure.
The estimated size of the femoral component
influences the length of the incision. Although the goal
of a less invasive technique is to complete the surgery
with an approximately 10 cm-14 cm incision, it may
be necessary to extend the incision if visualization is
inadequate or if there is excessive tension on the skin.
If the incision needs to be extended, it is advisable to
extend it gradually and only to the degree necessary.
However, the advantage of this MIS technique is
minimizing damage to the extensor mechanism and
failure to consider excessive tension on the skin may
lead to wound problems.
Make a slightly oblique parapatellar skin incision,
beginning approximately 2 cm proximal and medial
to the superior pole of the patella, and extend it
approximately 10 cm to the level of the superior
patellar tendon insertion at the center of the tibial
tubercle (Figure 5). Be careful to avoid disruption of
the tendon insertion. This will facilitate access to the
vastus medialis obliquus, and allow a minimal split
of the muscle. It will also improve visualization of the
lateral aspect of the joint obliquely with the patella
everted.
Divide the subcutaneous tissues to the level of the
retinaculum.
Figure 5