KNEE NAVIGATION, THE LEARNING CURVE

Introduction Using a new surgical technique for the first time involves a ‘learning curve’. The aim of this study is to assess the technical errors encountered in the early utilisation of a computer assistance system during total knee arthroplasty and to see if this error rate decreases with experience. Methods Thirty-two total knee replacement procedures performed by a single surgeon using the Stryker Knee Navigation system for the first time, were monitored. All technical difficulties were documented. We compared the complications encountered in the first five cases against the following 27 cases. Results Technical difficulties related to the navigation equipment were noted in four of the 32 cases (12.5%). These included (one case each); errors in tibial pin placement, concern over initial navigation readings, pin loosening, and dropping the navigation shim plate. There was a significant decrease in technical difficulties encountered in the later cases (7%) compared to the first five cases (40 percent, p= 0.041). Additionally, in three of the 32 cases (9%) the surgeon used their clinical judgement to override the navigation readings and recut the bone, to take ligament balancing into account. Conclusions A steep learning curve is involved when first utilising the Stryker Knee Navigation system. It is recommended that adequate training is undertaken prior to utilising knee navigation. The computer readings should be considered carefully and clinical judgement should not be overridden. In relation to the conduct of this study, one or more of the authors is in receipt of a research grant from a non-commercial source.