[Innovated Judet Ribs Plates - Preclinical Study, First Clinical Experience].

PURPOSE OF THE STUDY Based on the experience with using the Judet plates in stabilization of rib fractures an innovated Judet plate was constructed in cooperation with the Development Department of Medin company. During the preclinical part of the project, following the construction of the new Judet plate, a surgical technique was elaborated. Subsequently, the clinical application of rib osteosynthesis with innovated plates was commenced. MATERIAL AND METHODS In the course of the last three years the innovated Judet rib plate including the instruments were constructed by the Development Department of Medin company in cooperation with the Trauma Centre and the Department of Surgery of the University Hospital Královské Vinohrady. The goal of the innovation was the changes in technical parameters of rib plates which are compared with the new plates of other companies: 1. Adequate plate stability along the rib axis. 2. Creation of fixation clips for a stable, but not traumatized fixation of the plate around the rib. 3. Decreased robustness of the plate with sufficient stiffness. 4. Working out of a new technique of plate fixation with the use of new instruments. 5. Ensuring plate fixation with cortical locking screws. In the preclinical part of the project osteosynthesis of the broken rib was performed with a plate on a chest model for the basic types of rib fractures. Subsequently, the plate was used for rib osteosynthesis in a cadaver. The goal of the new instruments was besides temporarily maintaining the rib fracture reduction also the subsequent temporary application of plates with the assistance of fixation tongs before the final fixation of plates. In 2017, the clinical part of the project on the stabilisation of flail chest with the innovative Judet plates was launched. This type of innovative Judet plates has so far been used in 3 patients. RESULTS As to the surgical technique of ribs osteosynthesis: The profile of the plate has been adapted to the rib profile and can be further adjusted to rib curvature, also the fixation shoulders of the plates have been reshaped. The innovated plate has been complemented with a new configuration of fixation clips and the possibility to fix the plate with locking screws. The used cortical locking screws enable appropriate stabilisation of plates. They were tested on a laboratory model of ribs and on a cadaver using the new set of instruments. The plates can be easily shaped with tongs. The anchorage of fixation clips is adequately provided for also by means of tongs. The plates can be fixed to the rib without any significant compression of intercostal nerves. The essential change of the innovated Judet plate is its weight, which meets the contemporary trends in construction of rib plates designed for anatomical fixation. The first experience with the innovated plates in flail chest injury confirmed the safety of the procedure for stable osteosynthesis of rib fractures. Adequate stability of the chest wall facilitated an early withdrawal of ventilatory support. Osteosynthesis of rib fractures with innovated plates performed in the first three patient was without complications, including in the postoperative period. DISCUSSION A series of prospective studies prove the correctness of the indications of early rib osteosynthesis in flail chest. Further indications for rib osteosynthesis are postinjury chest deformity, dislocation of rib fracture fragments with a lung injury, and malunion of rib fracture. According to these studies the surgical stabilisation of the chest is a safe and efficient method resulting in pain reduction, decrease of ventilatory support time, and also in reduced morbidity. For rib osteosynthesis anatomical plates, Judet plates and intramedullary plates are used. Our innovation of the Judet plate aimed to improve the technical parameters of the plate. The innovative Judet plate means a significant improvement in technical parameters and stands comparison with the plates of others companies, which are used in the Czech Republic. This is also evidenced by preliminary clinical results. CONCLUSIONS Surgical stabilisation of the flail chest segment is considered to be he method of choice in treating selected patients, leading to the improvement of respiratory function and shortening of the ventilatory support time. The new technical parameters of the plate, including its weight, new fixation clips, locking screws and instruments are the priorities of the innovated Judet plates. The innovation of Judet plates represents an important step towards the extension of indications for surgical stabilisation of the chest. Key words:innovative Judet plates, preclinical study, osteosynthesis of rib fractures.