Italian version

COMPUTER ASSISTED PROSTHETIC RECONSTRUCTION OF THE KNEE

Since May 2002 we have been performing knee arthroprosthetic surgery using a computer assisted surgical technique; that is by using a "computerised navigation station" capable of supporting, advising and guiding the surgeon in the various phases of the surgical operation.

This instrument is called "NAVIGATOR" and includes a software, a system of infrared diods to determine the position of the limb, and a special device for the acquisition and processing of data. Such instrument allows the rapid determination of the best possible coordinates of the limb that needs to be operated (mechanical axis of the femur and of the tibial bone, tibiofemural angle). As a consequence, the surgeon has an immediate availability of practical information that allows him to perform the correct surgical procedures (positioning of the prosthesis, its right size, positioning of the guides for the incision, articular balancing). Therefore, the new method can replace the traditional pre-operative planning.

The surgeon receives all the necessary information directly in the operating room, he/she visualises it on a liquid crystals, touch-sensitive screen; such characteristics allow interactive action and, if necessary, allow changes on the parameters proposed by the computerised system.

Sensors are used and they are temporarily inserted into the bone through the same cutaneous incision performed for the surgery itself.

This way, the images and the information obtained are far more precise than if obtained through traditional surgical instruments.

The main obvious advantage is the fact that it is now possible to put the patient's operated limb in the best possible position, thus reducing the risk of a wrong positioning of the prosthesis.