Training benefits of computer navigated total knee arthroplasty

Computer navigation aims to improve the surgical accuracy of total knee replacement by more reliably placing the cutting blocks in the optimum location in order to create a neutral mechanical axis. Aside from the obvious clinical benefit to the patient, we believe computer navigation has a valuable role as a training tool. The aim of this study is to demonstrate the effectiveness of computer navigation as a training tool in total knee arthroplasty.

We performed a training exercise using Sawbone plastic models to simulate four common sources of error in the saw technique; 1. cutting guide movement due to inadequate fixation, 2. the effect of using slotted or open cutting guides, 3. the effect of bending the saw blade, and 4. the effect of recutting on the accuracy of the intended resection.

We found that bony resection errors resulted from; use of less than three pins to fix the cutting guide, use of open cutting guides, deliberate and inadvertent "hanging" or "lifting" of the saw on the cutting guide and recutting after moving the cutting guide.

The immediate feedback provided by computer navigated TKA allows surgeons and trainee surgeons the opportunity to improve the accuracy of their technique and increase awareness of their individual sources of error in TKA.

Used as a teaching tool, computer navigation can immediately identify errors in surgical technique and target subsequent training to minimise these errors. Training can be conducted whilst ensuring there is no detriment to patient safety.