The correct placement of implants around the knee relies on measurements made in the operating theatre and the skill of the surgeon. Precise alignment is important and in an attempt to improve the positioning of implants a number of computer navigation systems have been developed.
Optical tracking systems
The commonest type of system uses an optical tracking system to follow the position of the instruments. Anatomical landmarks are marked by the surgeon and these are referenced using metal markers that can be detected by he scanning device. The metal markers are attached by pins drilled into the bones of the femur and the tibia through small additional incision.This allows the surgical cuts to be made extremely accurately, ensuring ideal placement of the implants.
A typical optical navigation system in use
There is no doubt that computer-navigated surgery improves the accuracy and reliability of the positioning of knee replacements. Disadvantages are that the insertion of metal markers is invasive and time consuming and not all surgeons consider the extra time and expense involved of value in every case. Certain difficult cases do benefit from the technique and its use is a surgeon and patient preference rather than being considered essential at present.
The computer graphics generated during surgery showing bone and implant alignment
We have been undertaking computer-navigated knee replacement surgery at London Knee Clinic for several years. There are particular cases where it is especially valuable and we would recommend it. In most cases, however, it is an option we are happy to provide, but it is by no means always necessary and the additional equipment and surgical time does involve an additional expense. If you have medical insurance, you may or may not always be covered for this. For further information please get in touch.
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