Master Techniques in Orthopedic Surgery Knee CH27

345

27 Mobile-Bearing Medial Unicompartmental Knee Arthroplasty

FIGURE 27-1. After midvastus exposure, the intramedullary rod is placed as a guide for flexion of the femoral component. In addition, note that it can be used as a patellar retractor.

FIGURE 27-2. Marked center of the medial femoral condyle.

FIGURE 27-3. Removal of a small amount of tibial cartilage on the most lateral and posterior aspect of the tibia before placement of the femoral drill guide is helpful in preventing the guide translating medial into the tibial cartilage defect.

Milling of the Distal Femur To begin milling the distal femur, use the zero spigot by placing it into the 6-mm drill hole until the flange is down on bone. It is designed to remove enough bone for the femoral component to seat and this sets your zero position for additional distal femur resection. To get the circular mill in, it will be

FIGURE 27-4. Place the femoral drill guide onto the femur such that the 4- and 6-mm drill holes lie over the center line of the femoral condyle. Note that the handle of the drill guide should be parallel to the long axis of the tibia.

FIGURE 27-5. Link the femoral drill guide with the hinged elbow of the guide pointing laterally. Flex and extend the knee until the arms of the guide fall “into place” and the intramedullary guide and guide are linked.

FIGURE 27-6. Drill the anterior smaller 4-mm hole followed by the 6-mm drill hole.

Made with FlippingBook Learn more on our blog