Biomechanical analysis of modified plate of tplo in experimental model of proximal gap in synthetic tíbias canines

Author(s)

Guilherme Sembenelli

• Document type: Master's Dissertation
• Institution: Universidade Estadual Paulista (Unesp)
• Defense date: 2017-05-30
• Advisor: Luis Gustavo Gosuen Gonçalves Dias

Abstract

The aim of this study was to develop modified TPLO locked plate and to evaluate the effectiveness of stabilization provided by the implant developed compared to two other conventional methods of stabilization (locked plate and plate-rod). Through biomechanical studies the constructions were evaluated to craniocaudal and mediolateral bending, axial compression and torsional forces. Sixty synthetic tibias were used divided into three groups. Group 1 (modified TPLO plate), Group 2 (locked plate) and Group 3 (plate-rod) were subdivided into four groups of five tibiae. The tests were perfomed until failure of the construction (implants / tibia) and the results compared between the groups. The variables studied were analyzed under a completely randomized design in the factorial scheme 3 by 4 with 5 replicates for each combination of the factorial scheme. The results were submitted to analysis of variance and the means compared to each other by the Tukey test at 5% probability. In the axial compression test there was a significant difference in relation to the variable maximum force in which Group 3 obtained higher mean, not having significant difference between Groups 1 and 2. All constructions failed due to plate bending in the gap region of the synthetic tibia. In the three-point craniocaudal flexion test there was a significant difference in relation to the three variables studied. In the variable force maximum G2> G3 = G1, in the variable deflection G3> G1 = G2 and in the variable stiffness G3 = G2, G2 = G1 G3> G1. All constructions failed because of the breaking of the synthetic tibia. In the three-point craniocaudal flexion test there was a significant difference in relation to the three variables studied. In the variable force maximum G2> G3 = G1, in the variable deflection G3> G1 = G2 and in the variable stiffness G3 = G2, G2 = G1 G3> G1. All constructions failed because of the breaking of the synthetic tibia. In the mediolateral flexion test there was a significant difference in relation to the stiffness variable in which G3> G2 = G1. All constructions failed due to plate bending in the gap region of the synthetic tibia. In the torsion test there was a significant difference in relation to the variables angle at peak torque and stiffness. In the variable angle at the torque peak G2> G1 = G3. In the stiffness variable G1 = G3> G2. All constructs failed due to the breaking of the synthetic tibia distally to the plate. It is concluded that the modified TPLO plate presented biomechanical similarity with the conventional plate in most of the studied variables. The groups of locking plate an plate-rod constructions obtained higher stiffness indices compared to the other two groups, except for the torsion test in which the modified TPLO plate group had the same stiffness index as the plate and plate-rod. (AU)

• FAPESP's process: 15/14602-8 - Development of modified TPLO plate and comparative biomechanical test with other two methods of bone stabilization (locking plate and locking plate associated with intramedullary pin) in experimental proximal gap in synthetic tibias
• Grantee: Guilherme Sembenelli
• Support Opportunities: Scholarships in Brazil - Master