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NexGen MIS LPS-Flex Mobile Implant System
Surgical Technique
MIS Multi-Reference
®
4-in-1 Instruments
MIS Multi-Reference 4-in-1 Instruments are designed
to help the surgeon accomplish the goals of total
knee arthroplasty by combining optimal alignment
accuracy with a simple, straight-forward technique.
The instruments promote accurate cuts to help ensure
secure component fixation.
The MIS Multi-Reference 4-in-1 Instruments provide
a choice of either anterior or posterior referencing
techniques for making the femoral finishing cuts. The
anterior referencing technique uses the anterior cortex
to set the A/P position of the femoral component.
The posterior condyle cut is variable. The posterior
referencing technique uses the posterior condyles
to set the A/P position of the femoral component.
The variable cut is made anteriorly. The posterior
referencing technique will help provide a consistent
flexion gap. Femoral rotation is determined using the
posterior condyles or epicondylar axis as a reference.
The instruments and technique assist the surgeon in
restoring the center of the hip, knee, and ankle to lie
on a straight line, establishing a neutral mechanical
axis. The femoral and tibial components are oriented
perpendicular to this axis.
Patient Selection
Total knee arthroplasty using a less invasive technique
is suggested for nonobese patients with preoperative
flexion greater than 90°. Patients with varus deformities
greater than 17° or valgus deformities greater than 13°
are typically not candidates for the MIS technique.
A common view among orthopaedic surgeons is that
certain patients have greater potential for achieving
higher flexion after knee replacement. Patients with
good flexion preoperatively tend to get better range
of motion postoperatively.
The NexGen LPS-Flex implants are designed to safely
accommodate high flexion of up to 155°.
To optimize use of the high-flexion design elements,
the following criteria should be considered:
• The patient should have a need and desire to
perform deep-flexion activities. This need may
be dictated by activities specific to daily living,
leisure and recreation or job performance that
may require high-flexion capability, as well as
cultural or social customs where practices such
as frequent kneeling, sitting “cross-legged”, and
squatting are common.
• The patient should be capable of reaching 110°
of flexion preoperatively with a reasonable
probability of achieving a range of 125°
postoperatively.
• The length of time the patient has not performed
high-flexion activities should be considered.
• In patients with severe deformity preoperatively,
patient expectation for achieving high flexion
should be considered.
To prepare the patient for surgery, it may be helpful for
the patient to perform mobility exercises to prepare
the ligaments and muscles for the postoperative
rehabilitation protocol.
Please refer to the package inserts for complete
product information, including contraindications,
warnings, precautions, and adverse effects.
