Today I will be discussing the ConforMIS iView. The iView consists of two pages and is provided for each custom knee replacement patient to the surgeon around two weeks before the procedure is scheduled to take place. The iView is a customized plan based off of a patient’s CT scan.
The first page of the iView shows us the tibial images. The first set of images shows us exactly where the tibial cutting jig should sit on the bone. As the surgeon is proceeding with the procedure, he will reference this image to ensure that the tibial cutting jig, otherwise known as the T-1 jig is in the proper location. Once the proper location has been established, the surgeon can then pin this jig into place and proceed in cutting away the proximal portion of the diseased tibia.
After the resection has been completed, the surgeon can take the resected bone to his back table and measure the cut’s thicknesses. ConforMIS will provider five different locations where the cut thickness can be measured, as well as the values at each of these locations.
If the surgeon, while measuring their resected bone finds that the amount of bone resected does not match what ConforMIS provided, the surgeon can then go back to their jig and continue to cut more bone until the proper amounts has been removed.
The next image is going to show the surgeon how the implant should sit on the patient’s tibia. This is important because the surgeon wants to make sure that the final implant is not malrotated. And the surgeon also wants to be sure that there is no overhang of the implant over the bone, and no significant under coverage.
Since the ConforMIS implants are customized to each patient respecting the shape of their native anatomy, as long as the implant is in the correct location, there should be no overhang, minimal under coverage, and no malrotation.
The final image is going to show the surgeon, the poly thicknesses that have been provided, as well as the thickness of each, and the final image is going to show the surgeon the thickness of each poly, as well as the difference between the medial side thickness of the poly and the lateral side thickness of the poly.
The next page of the IView is going to show the surgeon the femoral images. The very first image is going to provide details as to where the very first jig should sit on the bone. The surgeon will reference this picture as he is placing the jig on the bone. Once the proper location has been determined, he will then pin this jib into place and begin to cut the distal femur.
After the distal femoral bone has been resected, the surgeon will take this bone to his back table and measure the cut thicknesses. If the amount of bone cut does not match the amount of bone on the i-jig, excuse me, if the amount of bone cut does not match the amount of cut bone that ConforMIS recommended be removed on the iView, then the surgeon can go back to this jig and continue to cut more bone until the proper amount of bone has been resected.
Next, the surgeon will place his three in one block, otherwise known as his F-4 onto the bone. He will ensure that the medial profile of the jig lines up with the medial profile of the patient’s bone. Once the proper location has been confirmed, and the jig has been pinned into place, the surgeon can now proceed with cutting away the patient’s anterior bone, as well as their posterior condyles.
Once these resections have been completed, the surgeon once again has the option of taking the resected bone to his back table and measuring the cut thicknesses, and making sure that that matches with the amount of bone ConforMIS recommended being resected. If there is a mismatch, the surgeon can continue to cut more bone until the proper amounts of bone has been removed.
The final picture, the final set of pictures of the iView are going to show how the final implant construct will look inside the patient’s knee. The surgeon will be given a picture of this final construct from the front and the back with the knee straight, as well as from the front and the side with the knee flexed at 90 degrees.