| Popis: |
The results obtained by the extensive experiments with the telemanipulator system clearly revealed the potential of robotic systems supporting fracture reduction of the femur. Not only is it possible to achieve very high accuracies in the reductions, but also the exposure of the operation team to X-ray radiation can be reduced, utilizing a robotic system in the presented way. The direct and well controlled motions of the robotically moved fracture segments might support a gentle reduction, when compared with manually performed reductions, which generally suffer from repetitive motions under high forces, implying high stress to the soft tissue surrounding the fracture. However, whether or not this really has an impact on the healthy soft tissue, will have to be proven in the future. One further point is remarkable here. The operation time could not be reduced utilizing a robot as telemanipulator when compared to the manual control groups. Keeping in mind the experience from clinical practice this is a surprising result, because from the possibility of a direct and well defined motion control utilizing the robot in combination with high resolution and detailed 3D imaging data we would have expected to shorten the operation time significantly. So far we haven't been able to determine the reasons for this, but the surgeon who performed the manual control groups observed, that the rigid soft tissue situation in the formalin conserved specimens eases the reduction considerably. How this circumstance influences the telemanipulated reductions and the results obtained by it too, can only be hypothesized at this time. Future experiments on fresh cadavers with soft tissue properties very close to the real life surgical situation will have to be done in order to clarify this point. The implemented way of visualizing the fracture and interacting with the robotic system by means of a simple input device with two main and one supplementary DoF has proven to be very efficient and intuitive for the surgeons, who performed the experiments. However, this input device has its limitations, as torques can not be fed back intuitively via its force feedback interface. Future work will have to be done in order to evaluate whether input devices with six DoFs for input as well as force/torque feedback might have the potential of further improving this telemanipulated robotic approach. In this context the evaluation of how much of the benefit of the present method is due to the 3D fracture visualization and how much is due to the robotized fracture reduction would be of interest, too. Comparing the robotized reductions with reductions manually performed but supported by a navigation system with 3D visualization capabilities like (Hazan & Joskowicz, 2003; Joskowicz et al., 1998a) can answer this question. |
