1. ACTIVMOTION

2. ACTIVMOTION
GENERAL THEORY
Lower limb can present as an inward (varus) or outward (valgus) angulation.
If mechanical axis is deviated, can get overloading and wearing of the cartilage on one side.

3. ACTIVMOTION
GENERAL THEORY
Closing wedge osteotomy: External bone wedge removal (with an osteotomy from the fibula).

4. ACTIVMOTION
GENERAL THEORY
Opening wedge osteotomy: Medial osteotomy of the tibia with the addition of illiac crest or bone substitute to fill the bone gap.

5. The medial tibial plateau supports most of the weight bearing.
ACTIVMOTION
Stress distribution in a healthy knee
The medial tibial plateau supports most of the weight bearing.
During walking the stress is predominantly anterior.
 Mechanical stress antero-medial.
The ratio is about 70% of the load on the medial plateau and 30% on the lateral one.

6. Creates a postero-anterior stress inside the knee.
ACTIVMOTION
Stress distribution in a healthy knee
During the roll back process of the knee (standing up, kneeling down…), the body weight stress oscillates between the posterior side of the tibial plateau and the anterior side of the plateau.
Creates a postero-anterior stress inside the knee.
While standing up, the load goes from 80% on the back and 20% on the front to 20% on the back and 80% on the front.

7. Mechanical axis passes outside from the articulation.
ACTIVMOTION
Stress distribution in a knee in Varus
In Varus :
Mechanical axis passes outside from the articulation.
Medial compartment supports 100% of the stress.

8. Same impact as in a healthy knee.
ACTIVMOTION
Stress distribution in a knee in varus
Same impact as in a healthy knee.
While standing up, the load goes from 80% on the back and 20% on the front to 20% on the back and 80% on the front.

9. After osteotomy, +3° valgus.
ACTIVMOTION
Stress distribution in a corrected knee
After osteotomy, +3° valgus.
The ratio is about 60% of the load on the lateral plateau and 40% left on the medial one.
During walking, the stress is still predominantly anterior.

10. Same impact as in a healthy knee.
ACTIVMOTION
Stress distribution in a Corrected Knee
Same impact as in a healthy knee.
While standing up, the load goes from 80% on the back and 20% on the front to 20% on the back and 80% on the front.

11. Post-op care too long (6 weeks) before putting patients on load.
ACTIVMOTION
NEWCLIP’S Technology as problem solver
Problem :
Post-op care too long (6 weeks) before putting patients on load.
Material may fail when putting on earlier load.
NCT solution :
Design an antero-medial plate for an optimal answer to the biomechanics of the knee.

12. Stress distribution on the plateau : Lateral
ACTIVMOTION
ACTIVMOTION CONCEPT
Stress distribution on the plateau :
Lateral
2+1 system :
2 screws under the external plateau. (Minimum 60% of the load).
1 screw under the internal plateau. (Maximum 40%of the load)
Antero-medial positioning to be as close as possible to the lateral stress.
Medial

13. Dynamic stress inside the knee during walking :
ACTIVMOTION
STRESS ABSORPTION
Dynamic stress inside the knee during walking :
Antero-medial positioning of the implant, to face the main anterior forces during walking.
Antero-medial positioning limits the tibial internal-rotation of the distal fragment and preserves the lateral hinge.
Antero-posterior orientation of the screws answering the roll-back of the knee.

14. Problem : ACTIVMOTION Lateral
STRESS ABSORPTION : SUMmary
Problem :
Post-op care too long (6 weeks) before a full weight bearing.
Early weight bearing has to be possible.
Lateral
NCT solution :
2+1 system & antero-medial positioning.
Hold up to 2.5 T when static.
Early weight bearing possible if no pain.
Medial

15. Why should an implant supports that much of a load ?
ACTIVMOTION
NEWCLIP’S Technology as problem solver
Why should an implant supports that much of a load ?
Leverage effect :
knee supports more than the weight of the body (while standing up, kneeling down…)
Up to 8 times the weight of the body.

16. ACTIVMOTION
NEWCLIP’S concept : solving the problem
Problem :
The lateral cortex has to remain intact, as bone growth will start from it.
To respect it, Pes Anserinus and MCL have to be progressively released distally.
NCT solution :
Antero-medial positioning with anatomical implant based on bone-mapping technology.
Compact and thin implant allowing the recommended HTO surgical approach.

17. NCT/Orthofix solution : Specific implant
ACTIVMOTION
HTO & ACL Recon
Problem:
Classic treatment: ACL recon followed by HTO.
Post-op care too long.
Sport-medicine approach: both at the same time.
No specific HTO implant on the market.
NCT/Orthofix solution : Specific implant
Two variable angle screws.
Specific positioning.

18. ACTIVMOTION
Surgical Approach
An 8-cm slightly oblique vertical incision is made along the antero-medial surface, running over the joint space down to under the tibial tuberosity.

19. A single-plane incision is made through the periosteum.
ACTIVMOTION
Surgical Approach
A single-plane incision is made through the periosteum.
The hamstring and the medial collateral ligament (MCL) are retracted posteriorly.
The larger the angular correction must be, the more the hamstring and MCL should be released distally.

20. ACTIVMOTION
Surgical Approach
Elevator used over the posterior surface of the tibial and remain as protection.
Clear the deepest part of the patellar tendon down to its attachment onto the tibial tuberosity, and protect it using a retractor during the osteotomy.

21. ACTIVMOTION
Surgical Technique
Incise upward toward the head of the fibula and stop incision 5-10mm before the lateral cortical area.

22. The angular correction is maintained during osteosynthesis.
ACTIVMOTION
Surgical Technique
Insert wedges of gradually larger size until finding the appropriate one (6-16mm).
The angular correction is maintained during osteosynthesis.

23. Position the plate onto the antero-internal side.
ACTIVMOTION
Surgical Technique
Position the plate onto the antero-internal side.
Proximal part of the plate runs parallel to the osteotomy cut.

24. ACTIVMOTION
Surgical Technique
Fit the first Ø3.5mm guide under the osteotomy cut, then start drilling using a Ø3.5mm drill.
Fit a second Ø3.5mm guide into the polyaxial slot of the plate. Adjust the drilling to the lateral tibial plateau.

25. ACTIVMOTION
Surgical Technique
The synthesis is complete when each screw has been perfectly tightened.

26. ACTIVMOTION
Surgical technique
The MBCP bone substitute : 60% of hydroxyapatite and 40% of tricalcic phosphate.
Proposed in several sizes corresponding to the osteotomy correction (6 to 16mm).

27. Cage as bone substitute holder. Avoid bone substitute migration.
ACTIVMOTION
Surgical technique
Cage as bone substitute holder.
Avoid bone substitute migration.
Optionnal.

28. ACTIVMOTION
SUM Up
NCT innovation :
2 + 1 system. 2 screws under external plateau, 1 screw under internal plateau for better weight bearing load care.
Antero-internal positioning of the plate.  orientation of the screws in the direction of the postero-anterior roll-back induced stress.
Low profile implant  Doesn’t interfere with the hamstring ligaments, patient don’t feel it under-skin.
Combination of ACL reconstruction and HTO. Specific implant that leave room for the tunnel.

29. Xavier Peiffert International Product Manager
THANK YOU
Xavier Peiffert International Product Manager