Today I’d like to talk a little about the conformace eye view. The first one I’m looking at is a left knee. The very first page of the eye view will reference the tibia. The first image on this page is going to show us how the tibial iJig should be seated on the bone during this custom knee replacement.
So, the surgeon will reference this intraoperatively and preoperatively. Preoperatively what we’re going to look at are the number of osteophytes on the bone. The osteophytes serve as great reference points to help ensure the proper seating of the jig. Intraoperatively we will double check our jig placements on the bone with the image that conformace provided to make sure that they match. Any adjustments that need to be made, can be made in this time.
The next image is a view of the knee from the side. What you’re going to be provided here is the patient’s native slope, which in this instance is seven degrees. And you’re also going to be provided the slope that the cuts is going to be made at which for this knee will be zero degrees.
So, since the patient’s slope is seven degrees and we’re cutting at zero degrees, which is a straight cut. Then what’s going to happen at the anterior or front of the bone, we are going to have a higher cut or a thicker cut than we will posterior section. This is not a concern. It’s just something we want the surgeon to be aware of so that when he makes his cut, he knows that he got what he was supposed to get.
The third image on the eye view is going to show the shape and thickness of the tibial cut conformace will provide five reference points that the surgeon can utilize to measure the actual cut bone versus the cut values that conformace, said they should be at. If the cut bone value is lower than what conformace had recommended, then at this point, the surgeon can go back and make adjustments.
The final bit of data that we want you to look at here is the L L cut value. L L stands for lowest point lateral. If this number is seven millimeters or greater, it is often recommended that the surgeon take two millimeters, less bone in order to help ensure the thinnest possible Poly is implanted into the patient.
The next image on the tibial page of the eye view is going to show us how final implants on the tibia should be positioned. This will help ensure the implant is not malrotated and that there is no overhang of the implant of the bone and no significant under coverage.
The final image is going to show us the patient’s Poly thicknesses, as well as the patient’s unique distal femoral offset. So, with every knee, the medial thickness of the Poly will be 6.1 millimeters, 8.1 millimeters, and 10.1 millimeters as well as a 14.1 millimeter.
And the lateral side is going to be the thickness of the medial side, plus the patient’s distal femoral offset. So in this instance, the patient’s distal femoral offset is 0.7 millimeters thicker than the medial side. So, if the medial side is 6.1 millimeters, then the lateral side will be 6.8 millimeters.
The next page of the eye view is the femoral side. On this patient, what we’re looking at are the locations of the osteophytes, as well as how the jig references those osteophytes in order to ensure optimal placement. The surgeon will look at this image, preoperatively and intraoperatively to make sure that the jig is seated correctly, which will help guarantee that we get the recommended resection values.
The next image is going to show us the placements again of the distal femoral cutting jig, as well as the cut thicknesses of the distal femur. After the surgeon makes his distal femoral cuts, he will take the resected bone to the back table and measure it with a caliber to ensure that the amount of bone that has been removed is the same as the amount of bone that can form this recommended we removed. If there are any discrepancies, it can be fixed at this moment.
The next image is just going to show the surgeon, the angle of his distal femoral cuts that he just made, as well as the angle of the anterior femoral cuts that he’s about to make.
The next image shows the F4 or B1 block. The first thing the surgeon should know about this image is that the medial profile of this jig is going to match perfectly with the medial profile of the patient’s bone. This helps ensure proper placement as well as helps to ensure adequate resection values.
Conformace will provide the thicknesses of the anterior cut as well as the posterior femoral congela cuts. After the surgeon resets the bone, all the cut bone can be taken to the back table and measured to ensure that the cut values are in line with what conformace provided. If there are any discrepancies, the surgeon can address them at this point.
The final set of images of the eye view, are going to show us how the final implants going to look while the knee is straight from both the front and the back, as well as how the knee’s going to look bent from the front and the side.
I am fellowship trained in joint replacement surgery, metabolic bone disorders, sports medicine and trauma. I specialize in total hip and knee replacements, and I have personally written most of the content on this page.
You can see my full CV at my profile page.
