Page 16 - KNEETA

KNEETA R

Total Knee system

The goal of any total

knee implant system

is to provide the patient with a long-lasting solution that addresses
their knee pain. However, patient expectations and satisfaction
levels have steadily increased and patients require an option that
most closely replicates the function of the normal knee. Multiple
studies have characterized the movement of the normal knee,
illustrating greater posterior translation of the lateral condyle over
1,2 The normal knee has

than conventional knee implants. As such, the need for a long-
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lasting knee system that can achieve normal knee kinematics, is
stable throughout the range of motion, and incorporates features

Conventional knee implants have been developed to rely either on
soft tissue or a post and cam mechanism to predictably roll back,
providing posterior translation of the femur on the tibia during

phenomenon does not occur with many conventional knee
designs, especially those that incorporate a symmetric tibial insert.
These implants illustrate “paradoxical motion,” where the femoral

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instead of rolling back. This type of motion has been described
by patients as feeling like “walking on ice”. It is also one of the main
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problems the medial-pivot “ball-in-socket” philosophy solves.
In order to better understand the concept of the medial-pivot
“ball-in-socket” philosophy, a brief reference to the anatomic
structures that provide stability to the normal knee is necessary.
The normal anatomy provides features that give the knee
stability on the medial pivot side and that allow a more mobile lateral
pivot
stability that the lateral meniscus does not. This is largely due

tibia and extensively attached to the capsule and larger medial pivot
collateral ligament. The lateral meniscus, which lacks the
extensiveness of these attachments, is more mobile and may
displace up to 1cm. The ligaments in the knee also serve as
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stabilizers for the knee joint. The anterior cruciate ligament (ACL)
prevents posterior translation of the femur on the tibia, where
while the posterior cruciate ligament (PCL) is considered the
primary stabilizer of the knee. Being almost twice as strong
as the ACL, the PCL prevents posterior translation of the tibia on
the femur.

SUNTEK
Medical Devices
and Electronic
Products Trade Co. KNEETA® Medial-Pivot Knee System
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