|
[Technology opportunity 2007-070]
Surface Guided Total Knee
> Printer-friendly version
Description:
Researchers at Queen’s University have developed a fixed-bearing total knee system that
employs an innovative bearing surface design to guide the motion of the joint in both flexion
and extension and to attain normal kinematics in deep knee bending without the use of an
intercondylar cam/post.
Possessing inherent stability, the design generates an external rotation and posterior roll-back
of the femur consistent with that of the normal knee during deep knee flexion. As such,
impingement caused by paradoxical motion is reduced and a high range of motion is possible.
The design accommodates both PCL retaining and bi-cruciate retaining surgical approaches and
permits normal patella mechanics over the entire range of motion.
Figure 1: Kinematics of the lateral femoral condyle
Top: Schematic of the
articulation of the device when
tested in a joint simulator under a compressive load.
Femoral posterior roll-back of
23mm and external rotation of
20° are observed during flexion
between 0° and 150°. |
Bottom: Results from MRI
studies of the kinematics of the
lateral condyle in the normal
knee joint. Posterior roll-back
of 27±3mm and external
rotation of 18±2° are observed
during flexion.
Note: CP = Contact Point |
Advantages:
Advantages of this novel design include:
1. Normal knee kinematics during deep knee flexion without the use of an intercondylar
cam/post – 20° external rotation and 23mm posterior roll-back of the femur;
2. Impingement caused by paradoxical motion is reduced - a high range of motion is
possible;
3. Accommodates both PCL retaining and bi-cruciate retaining surgical approaches;
4. Permits normal patella mechanics over the entire range of motion;
5. Motion is guided in both flexion and extension; and
6. Lower contact stresses during deep knee bending may result in reduced wear and
improved long-term success.
Status of Development:
A proof-of-concept prototype has been made and its kinematics have been tested in a joint
simulator under various compressive loads.
Status of Commercialization:
PARTEQ Innovations, the technology transfer office of Queen’s University, is seeking industrial
partners interested in further developing and/or licensing the intellectual property.
Contact:
Jason Hendry
Manager, Commercial Development
Phone: 613. 533. 2342
Fax: 613. 533. 6853
Email: jhendry@parteqinnovations.com
|
