ENHANCED MID-RESECTION WORKFLOW TECHNIQUE FOR ROBOTIC ASSISTED TKA

Description

Robotic technology in total knee arthroplasty (TKA) has proven to improve accuracy of component position, achieve objective balance and desired alignment target. However, its role in gross deformity correction is not well established in literature. One of the key advantages of robotic assisted TKA over manual TKA is the ability to balance the knee before the bone cuts are made. This is known as pre-balance, and it’s done by altering the position of the components while causing least compromise to the soft tissues. Using boundaries set by principles of functional alignment if the knee pre-balances during dynamic joint balancing, pre resection workflow technique is used, and all the cuts are made simultaneously. If the knee does not balance mid resection workflow technique is used. Here the proximal tibia and distal femur cuts are taken, and the extension gap is balanced first by performing releases on the tibial side. Later flexion gap is matched to the extension gap. In our experience both workflows could not achieve balance in some severe varus deformities. The main reason is the presence of large osteophytes and tight posterior capsule on the femoral side, which are inaccessible till final cuts are done. The sub mm accuracy of the bone cuts provided by the robotic arm is taken advantage of, to make a provisional posterior-medial cut of the femur giving us access to these structures. This novel workflow technique has helped us balance knees irrespective of the quantum of deformity.