Precision surgery

Accurate component placement in joint replacement cannot be overemphasized; despite many re-engineering efforts over the past 3 decades, failure rates at 10 years for total hip arthroplasty (THA) and total knee arthroplasty (TKA) remain constant. Intraoperative decisions with joint replacement have been facilitated with manual instrumentation and are affected by the surgeon's intuition, instinct, and experience. Current technology allows the development and use of high-tech instrumentation, which, irrespective of surgeon-dependent variables, gives intraoperative quantitative information on which precise placement of hip and knee components can be done. Component placement is the single most important technical maneuver the surgeon accomplishes to prevent mechanical complications, which will nearly eliminate outliers from very good and excellent results and revision as a consequence of technical errors; computer navigation has almost made it possible. In knees it gives precise component placement in the coronal and sagittal planes, and in hips it particularly improves acetabular component position by numerical control of inclination, anteversion, and most importantly center of rotation. Precision is enhanced even more when computer navigation is elevated to the next level, which is robotic guidance. The preoperative plan set by the surgeon is executed by the robotic tool while the surgeon manually controls the robotic arm. Bone preparation cannot exceed the boundaries the surgeon has set, as the surgeon's manual force will stop the robot and the error cannot be made. Robotic surgery has progressed in the unicompartmental knee, and this innovation is in the final stages of development in THA.