Avaliação de um novo implante para tratamento de fraturas pósterolaterais do planalto tibial

Abstract

Objective: The objective of the study was to qualitatively evaluate the function of the semi-ring plate in the fixation of the posterolateral fractures of the tibial plateau. For this purpose, synthetic bone and anatomical pieces (knees) were used to validate the geometric structure of this new implant for the treatment of posterolateral tibial plateau. Methods: A new implant called "semi-ring plate" was designed, looking at the treatment of posterolateral fractures of the tibial plateau. The dimensions and geometry of the new plate were developed from literature data on the proximal anatomy of the tibia and the conventional L-plate as a reference. The dimensions of the new semi-ring plate allow, however, to support the entire lateral and posterolateral border of the tibial plateau. Results: The plate in development presents a horizontal arm that covers the entire lateral and posterolateral region of the tibial plateau. The width of the smaller horizontal arm in the semi-ring plate allows its positioning above the fibula head and under the lateral collateral ligament (LCL), reaching the posterior region of the lateral tibial plateau. The vertical arm of the plaque maintains the stability of the plate, in the sagittal plane, avoiding that there is axial instability of the osteosynthesis. Three tests were performed to fix the new plaque in synthetic bone and anatomical specimens, in order to evaluate its adaptation to the lateral and posterolateral borders of the tibial plateau. In the evaluations, macroscopic and radiographic, it was possible to observe an adequate adaptation between the morphology of the plate and the anatomy of the posterolateral region of the knee. Conclusions: In view of the performed evaluations, it was possible to infer that the developed implant allows a stable osteosynthesis, since it adapts well to the anatomy of the lateral and posterolateral region of the tibial plateau.