Abstract
Introduction
Two aspects are very important for knee joint replacement – restoration of biomechanical limb axis and achieving ligaments balance. Computer navigation allows us to do all this.
Material and methods
We analysed 94 knee joint replacement surgeries using computer navigation by “STRYKER”.
Results
There is no substantial difference between results of correction of biomechanical axis with computer navigation and without it in case of uncomplicated joint replacement. So, completer correction of axis (varus/valgus zero degrees) with computer navigation was achieved in 84% of cases versus 79% without navigation. There was varus or valgus deformity up to two degrees in 12% after surgery (without navigation −17% of cases). Error in deformity correction without application of navigation was three-five degrees in 4% of cases (all were challenging joint replacement). Advantages of navigation are obvious in case of large deformities, and also when insertion of intramedullary guide is undesirable or impossible.
Use of navigation requires good skills of joint replacement, because landmarks should be chosen precisely and possibility of error during determining the center of rotation for the femoral head should be taken into consideration.
Duration of surgery without navigation is 82.6±16.4 minutes and is much longer in the beginning of the learning curve (one hour longer or more). After acquiring skills the surgery takes 118±15.6 minutes.
Conclusion
We evaluate use of navigation system as a modern and in-demand trend.
Use of navigation should be started after getting good skills of joint replacement. Violation of the technology of determining landmarks leads to wrong virtual modeling and serious errors in positioning components.
Advantages of navigation are obvious in evident bone deformity, when it is impossible or undesirable to open a medullary canal.
