Patient-Specific Instrumentation (PSI)

PSI was developed as a new concept for providing patient-specific surgical instruments through computerized preoperative planning [1]. The process begins with preoperative CT or MRI image data being used to construct 3D images, which are then superimposed on a computer with the 3D image data of the TKA implant to be used. A virtual surgery called “surgical planning” is performed to confirm implant size, alignment, and position, as well as osteotomy volume. To this point, the process is similar to preoperative planning using 3D templates; however, PSI is an extension of this process.